diff --git a/.github/stale.yml b/.github/stale.yml
index e9cda3d9..3a5a354b 100644
--- a/.github/stale.yml
+++ b/.github/stale.yml
@@ -1,9 +1,10 @@
 ---
-# This configuration closes stale PRs after 30 days.
+# This configuration closes stale PRs after 28 + 7 days.
+# That's 4 weeks until stale bot complains, and a week until it closes a PR.
 # Issues in ALE are never, ever stale. They are either resolved or not.
 only: pulls
 daysUntilStale: 28
-daysUntilClose: 2
+daysUntilClose: 7
 exemptLabels: []
 staleLabel: stale
 markComment: >
diff --git a/ale_linters/asciidoc/languagetool.vim b/ale_linters/asciidoc/languagetool.vim
new file mode 100644
index 00000000..f16df6c0
--- /dev/null
+++ b/ale_linters/asciidoc/languagetool.vim
@@ -0,0 +1,5 @@
+" Author: Horacio Sanson (hsanson [ät] gmail.com)
+" Description: languagetool for asciidoc files, copied from markdown.
+
+
+call ale#handlers#languagetool#DefineLinter('asciidoctor')
diff --git a/ale_linters/c/cc.vim b/ale_linters/c/cc.vim
new file mode 100644
index 00000000..6d920ab0
--- /dev/null
+++ b/ale_linters/c/cc.vim
@@ -0,0 +1,53 @@
+" Author: w0rp <devw0rp@gmail.com>
+" Description: A C compiler linter for C files with gcc/clang, etc.
+
+call ale#Set('c_cc_executable', '<auto>')
+call ale#Set('c_cc_options', '-std=c11 -Wall')
+
+function! ale_linters#c#cc#GetExecutable(buffer) abort
+    let l:executable = ale#Var(a:buffer, 'c_cc_executable')
+
+    " Default to either clang or gcc.
+    if l:executable is# '<auto>'
+        if ale#engine#IsExecutable(a:buffer, 'clang')
+            let l:executable = 'clang'
+        else
+            let l:executable = 'gcc'
+        endif
+    endif
+
+    return l:executable
+endfunction
+
+function! ale_linters#c#cc#GetCommand(buffer, output) abort
+    let l:cflags = ale#c#GetCFlags(a:buffer, a:output)
+    let l:ale_flags = ale#Var(a:buffer, 'c_cc_options')
+
+    if l:cflags =~# '-std='
+        let l:ale_flags = substitute(
+        \   l:ale_flags,
+        \   '-std=\(c\|gnu\)[0-9]\{2\}',
+        \   '',
+        \   'g')
+    endif
+
+    " -iquote with the directory the file is in makes #include work for
+    "  headers in the same directory.
+    "
+    " `-o /dev/null` or `-o null` is needed to catch all errors,
+    " -fsyntax-only doesn't catch everything.
+    return '%e -S -x c'
+    \   . ' -o ' . g:ale#util#nul_file
+    \   . ' -iquote ' . ale#Escape(fnamemodify(bufname(a:buffer), ':p:h'))
+    \   . ale#Pad(l:cflags)
+    \   . ale#Pad(l:ale_flags) . ' -'
+endfunction
+
+call ale#linter#Define('c', {
+\   'name': 'cc',
+\   'aliases': ['gcc', 'clang'],
+\   'output_stream': 'stderr',
+\   'executable': function('ale_linters#c#cc#GetExecutable'),
+\   'command': {b -> ale#c#RunMakeCommand(b, function('ale_linters#c#cc#GetCommand'))},
+\   'callback': 'ale#handlers#gcc#HandleGCCFormatWithIncludes',
+\})
diff --git a/ale_linters/c/clang.vim b/ale_linters/c/clang.vim
deleted file mode 100644
index 681101fc..00000000
--- a/ale_linters/c/clang.vim
+++ /dev/null
@@ -1,24 +0,0 @@
-" Author: Masahiro H https://github.com/mshr-h
-" Description: clang linter for c files
-
-call ale#Set('c_clang_executable', 'clang')
-call ale#Set('c_clang_options', '-std=c11 -Wall')
-
-function! ale_linters#c#clang#GetCommand(buffer, output) abort
-    let l:cflags = ale#c#GetCFlags(a:buffer, a:output)
-
-    " -iquote with the directory the file is in makes #include work for
-    "  headers in the same directory.
-    return '%e -S -x c -fsyntax-only'
-    \   . ' -iquote ' . ale#Escape(fnamemodify(bufname(a:buffer), ':p:h'))
-    \   . ale#Pad(l:cflags)
-    \   . ale#Pad(ale#Var(a:buffer, 'c_clang_options')) . ' -'
-endfunction
-
-call ale#linter#Define('c', {
-\   'name': 'clang',
-\   'output_stream': 'stderr',
-\   'executable': {b -> ale#Var(b, 'c_clang_executable')},
-\   'command': {b -> ale#c#RunMakeCommand(b, function('ale_linters#c#clang#GetCommand'))},
-\   'callback': 'ale#handlers#gcc#HandleGCCFormatWithIncludes',
-\})
diff --git a/ale_linters/c/gcc.vim b/ale_linters/c/gcc.vim
deleted file mode 100644
index 1df1018e..00000000
--- a/ale_linters/c/gcc.vim
+++ /dev/null
@@ -1,28 +0,0 @@
-" Author: w0rp <devw0rp@gmail.com>
-" Description: gcc linter for c files
-
-call ale#Set('c_gcc_executable', 'gcc')
-call ale#Set('c_gcc_options', '-std=c11 -Wall')
-
-function! ale_linters#c#gcc#GetCommand(buffer, output) abort
-    let l:cflags = ale#c#GetCFlags(a:buffer, a:output)
-
-    " -iquote with the directory the file is in makes #include work for
-    "  headers in the same directory.
-    "
-    " `-o /dev/null` or `-o null` is needed to catch all errors,
-    " -fsyntax-only doesn't catch everything.
-    return '%e -S -x c'
-    \   . ' -o ' . g:ale#util#nul_file
-    \   . ' -iquote ' . ale#Escape(fnamemodify(bufname(a:buffer), ':p:h'))
-    \   . ale#Pad(l:cflags)
-    \   . ale#Pad(ale#Var(a:buffer, 'c_gcc_options')) . ' -'
-endfunction
-
-call ale#linter#Define('c', {
-\   'name': 'gcc',
-\   'output_stream': 'stderr',
-\   'executable': {b -> ale#Var(b, 'c_gcc_executable')},
-\   'command': {b -> ale#c#RunMakeCommand(b, function('ale_linters#c#gcc#GetCommand'))},
-\   'callback': 'ale#handlers#gcc#HandleGCCFormatWithIncludes',
-\})
diff --git a/ale_linters/cpp/cc.vim b/ale_linters/cpp/cc.vim
new file mode 100644
index 00000000..eed3898f
--- /dev/null
+++ b/ale_linters/cpp/cc.vim
@@ -0,0 +1,53 @@
+" Author: w0rp <devw0rp@gmail.com>
+" Description: A C++ compiler linter for C++ files with gcc/clang, etc.
+
+call ale#Set('cpp_cc_executable', '<auto>')
+call ale#Set('cpp_cc_options', '-std=c++14 -Wall')
+
+function! ale_linters#cpp#cc#GetExecutable(buffer) abort
+    let l:executable = ale#Var(a:buffer, 'cpp_cc_executable')
+
+    " Default to either clang++ or gcc.
+    if l:executable is# '<auto>'
+        if ale#engine#IsExecutable(a:buffer, 'clang++')
+            let l:executable = 'clang++'
+        else
+            let l:executable = 'gcc'
+        endif
+    endif
+
+    return l:executable
+endfunction
+
+function! ale_linters#cpp#cc#GetCommand(buffer, output) abort
+    let l:cflags = ale#c#GetCFlags(a:buffer, a:output)
+    let l:ale_flags = ale#Var(a:buffer, 'cpp_cc_options')
+
+    if l:cflags =~# '-std='
+        let l:ale_flags = substitute(
+        \   l:ale_flags,
+        \   '-std=\(c\|gnu\)++[0-9]\{2\}',
+        \   '',
+        \   'g')
+    endif
+
+    " -iquote with the directory the file is in makes #include work for
+    "  headers in the same directory.
+    "
+    " `-o /dev/null` or `-o null` is needed to catch all errors,
+    " -fsyntax-only doesn't catch everything.
+    return '%e -S -x c++'
+    \   . ' -o ' . g:ale#util#nul_file
+    \   . ' -iquote ' . ale#Escape(fnamemodify(bufname(a:buffer), ':p:h'))
+    \   . ale#Pad(l:cflags)
+    \   . ale#Pad(l:ale_flags) . ' -'
+endfunction
+
+call ale#linter#Define('cpp', {
+\   'name': 'cc',
+\   'aliases': ['gcc', 'clang', 'g++', 'clang++'],
+\   'output_stream': 'stderr',
+\   'executable': function('ale_linters#cpp#cc#GetExecutable'),
+\   'command': {b -> ale#c#RunMakeCommand(b, function('ale_linters#cpp#cc#GetCommand'))},
+\   'callback': 'ale#handlers#gcc#HandleGCCFormatWithIncludes',
+\})
diff --git a/ale_linters/cpp/clang.vim b/ale_linters/cpp/clang.vim
deleted file mode 100644
index e48291eb..00000000
--- a/ale_linters/cpp/clang.vim
+++ /dev/null
@@ -1,24 +0,0 @@
-" Author: Tomota Nakamura <https://github.com/tomotanakamura>
-" Description: clang linter for cpp files
-
-call ale#Set('cpp_clang_executable', 'clang++')
-call ale#Set('cpp_clang_options', '-std=c++14 -Wall')
-
-function! ale_linters#cpp#clang#GetCommand(buffer, output) abort
-    let l:cflags = ale#c#GetCFlags(a:buffer, a:output)
-
-    " -iquote with the directory the file is in makes #include work for
-    "  headers in the same directory.
-    return '%e -S -x c++ -fsyntax-only'
-    \   . ' -iquote ' . ale#Escape(fnamemodify(bufname(a:buffer), ':p:h'))
-    \   . ale#Pad(l:cflags)
-    \   . ale#Pad(ale#Var(a:buffer, 'cpp_clang_options')) . ' -'
-endfunction
-
-call ale#linter#Define('cpp', {
-\   'name': 'clang',
-\   'output_stream': 'stderr',
-\   'executable': {b -> ale#Var(b, 'cpp_clang_executable')},
-\   'command': {b -> ale#c#RunMakeCommand(b, function('ale_linters#cpp#clang#GetCommand'))},
-\   'callback': 'ale#handlers#gcc#HandleGCCFormatWithIncludes',
-\})
diff --git a/ale_linters/cpp/gcc.vim b/ale_linters/cpp/gcc.vim
deleted file mode 100644
index 108d6d70..00000000
--- a/ale_linters/cpp/gcc.vim
+++ /dev/null
@@ -1,29 +0,0 @@
-" Author: geam <mdelage@student.42.fr>
-" Description: gcc linter for cpp files
-"
-call ale#Set('cpp_gcc_executable', 'gcc')
-call ale#Set('cpp_gcc_options', '-std=c++14 -Wall')
-
-function! ale_linters#cpp#gcc#GetCommand(buffer, output) abort
-    let l:cflags = ale#c#GetCFlags(a:buffer, a:output)
-
-    " -iquote with the directory the file is in makes #include work for
-    "  headers in the same directory.
-    "
-    " `-o /dev/null` or `-o null` is needed to catch all errors,
-    " -fsyntax-only doesn't catch everything.
-    return '%e -S -x c++'
-    \   . ' -o ' . g:ale#util#nul_file
-    \   . ' -iquote ' . ale#Escape(fnamemodify(bufname(a:buffer), ':p:h'))
-    \   . ale#Pad(l:cflags)
-    \   . ale#Pad(ale#Var(a:buffer, 'cpp_gcc_options')) . ' -'
-endfunction
-
-call ale#linter#Define('cpp', {
-\   'name': 'gcc',
-\   'aliases': ['g++'],
-\   'output_stream': 'stderr',
-\   'executable': {b -> ale#Var(b, 'cpp_gcc_executable')},
-\   'command': {b -> ale#c#RunMakeCommand(b, function('ale_linters#cpp#gcc#GetCommand'))},
-\   'callback': 'ale#handlers#gcc#HandleGCCFormatWithIncludes',
-\})
diff --git a/ale_linters/elixir/credo.vim b/ale_linters/elixir/credo.vim
index 317ecab3..7c298502 100644
--- a/ale_linters/elixir/credo.vim
+++ b/ale_linters/elixir/credo.vim
@@ -46,7 +46,7 @@ function! ale_linters#elixir#credo#GetMode() abort
 endfunction
 
 function! ale_linters#elixir#credo#GetCommand(buffer) abort
-    let l:project_root = ale#handlers#elixir#FindMixProjectRoot(a:buffer)
+    let l:project_root = ale#handlers#elixir#FindMixUmbrellaRoot(a:buffer)
     let l:mode = ale_linters#elixir#credo#GetMode()
 
     return ale#path#CdString(l:project_root)
diff --git a/ale_linters/markdown/markdownlint.vim b/ale_linters/markdown/markdownlint.vim
index e935cbfe..7a293938 100644
--- a/ale_linters/markdown/markdownlint.vim
+++ b/ale_linters/markdown/markdownlint.vim
@@ -1,11 +1,22 @@
 " Author: Ty-Lucas Kelley <tylucaskelley@gmail.com>
 " Description: Adds support for markdownlint
 
+call ale#Set('markdown_markdownlint_options', '')
+
+function! ale_linters#markdown#markdownlint#GetCommand(buffer) abort
+    let l:executable = 'markdownlint'
+
+    let l:options = ale#Var(a:buffer, 'markdown_markdownlint_options')
+
+    return ale#Escape(l:executable)
+    \ . (!empty(l:options) ? ' ' . l:options : '') . ' %s'
+endfunction
+
 call ale#linter#Define('markdown', {
 \   'name': 'markdownlint',
 \   'executable': 'markdownlint',
 \   'lint_file': 1,
 \   'output_stream': 'both',
-\   'command': 'markdownlint %s',
+\   'command': function('ale_linters#markdown#markdownlint#GetCommand'),
 \   'callback': 'ale#handlers#markdownlint#Handle'
 \})
diff --git a/ale_linters/ocaml/ols.vim b/ale_linters/ocaml/ols.vim
index d8208c52..ec71bdb4 100644
--- a/ale_linters/ocaml/ols.vim
+++ b/ale_linters/ocaml/ols.vim
@@ -9,6 +9,6 @@ call ale#linter#Define('ocaml', {
 \   'lsp': 'stdio',
 \   'executable': function('ale#handlers#ols#GetExecutable'),
 \   'command': function('ale#handlers#ols#GetCommand'),
-\   'language_callback': 'ale#handlers#ols#GetLanguage',
+\   'language': function('ale#handlers#ols#GetLanguage'),
 \   'project_root': function('ale#handlers#ols#GetProjectRoot'),
 \})
diff --git a/ale_linters/reason/ols.vim b/ale_linters/reason/ols.vim
index 66137e1b..9fbd9b4f 100644
--- a/ale_linters/reason/ols.vim
+++ b/ale_linters/reason/ols.vim
@@ -9,6 +9,6 @@ call ale#linter#Define('reason', {
 \   'lsp': 'stdio',
 \   'executable': function('ale#handlers#ols#GetExecutable'),
 \   'command': function('ale#handlers#ols#GetCommand'),
-\   'language_callback': 'ale#handlers#ols#GetLanguage',
+\   'language': function('ale#handlers#ols#GetLanguage'),
 \   'project_root': function('ale#handlers#ols#GetProjectRoot'),
 \})
diff --git a/ale_linters/sh/shell.vim b/ale_linters/sh/shell.vim
index 171fe64e..73ab3608 100644
--- a/ale_linters/sh/shell.vim
+++ b/ale_linters/sh/shell.vim
@@ -1,5 +1,5 @@
 " Author: w0rp <devw0rp@gmail.com>
-" Description: Lints sh files using bash -n
+" Description: Lints shell files by invoking the shell with -n
 
 " Backwards compatibility
 if exists('g:ale_linters_sh_shell_default_shell')
diff --git a/ale_linters/swift/swiftformat.vim b/ale_linters/swift/swiftformat.vim
new file mode 100644
index 00000000..2504511a
--- /dev/null
+++ b/ale_linters/swift/swiftformat.vim
@@ -0,0 +1,62 @@
+" Author: Klaas Pieter Annema <https://github.com/klaaspieter>
+" Description: Support for swift-format https://github.com/apple/swift-format
+
+let s:default_executable = 'swift-format'
+call ale#Set('swift_swiftformat_executable', s:default_executable)
+
+function! ale_linters#swift#swiftformat#UseSwift(buffer) abort
+    let l:swift_config = ale#path#FindNearestFile(a:buffer, 'Package.swift')
+    let l:executable = ale#Var(a:buffer, 'swift_swiftformat_executable')
+
+    return !empty(l:swift_config) && l:executable is# s:default_executable
+endfunction
+
+function! ale_linters#swift#swiftformat#GetExecutable(buffer) abort
+    if ale_linters#swift#swiftformat#UseSwift(a:buffer)
+        return 'swift'
+    endif
+
+    return ale#Var(a:buffer, 'swift_swiftformat_executable')
+endfunction
+
+function! ale_linters#swift#swiftformat#GetCommand(buffer) abort
+    let l:executable = ale_linters#swift#swiftformat#GetExecutable(a:buffer)
+    let l:args = '--mode lint %t'
+
+    if ale_linters#swift#swiftformat#UseSwift(a:buffer)
+        let l:args = 'run swift-format' . ' ' . l:args
+    endif
+
+    return ale#Escape(l:executable) . ' ' . l:args
+endfunction
+
+function! ale_linters#swift#swiftformat#Handle(buffer, lines) abort
+    " Matches lines of the following pattern:
+    "
+    " Sources/main.swift:4:21: warning: [DoNotUseSemicolons]: remove ';' and move the next statement to the new line
+    " Sources/main.swift:3:12: warning: [Spacing]: remove 1 space
+    let l:pattern = '\v^.*:(\d+):(\d+): (\S+) \[(\S+)\]: (.*)$'
+    let l:output = []
+
+    for l:match in ale#util#GetMatches(a:lines, l:pattern)
+        call add(l:output, {
+        \   'lnum': l:match[1] + 0,
+        \   'col': l:match[2] + 0,
+        \   'type': l:match[3] is# 'error' ? 'E' : 'W',
+        \   'code': l:match[4],
+        \   'text': l:match[5],
+        \})
+    endfor
+
+    return l:output
+endfunction
+
+
+call ale#linter#Define('swift', {
+\   'name': 'swift-format',
+\   'executable': function('ale_linters#swift#swiftformat#GetExecutable'),
+\   'command': function('ale_linters#swift#swiftformat#GetCommand'),
+\   'output_stream': 'stderr',
+\   'language': 'swift',
+\   'callback': 'ale_linters#swift#swiftformat#Handle'
+\})
diff --git a/autoload/ale/assert.vim b/autoload/ale/assert.vim
index 291edcee..934fcaa8 100644
--- a/autoload/ale/assert.vim
+++ b/autoload/ale/assert.vim
@@ -130,7 +130,7 @@ endfunction
 function! ale#assert#LSPLanguage(expected_language) abort
     let l:buffer = bufnr('')
     let l:linter = s:GetLinter()
-    let l:language = ale#util#GetFunction(l:linter.language_callback)(l:buffer)
+    let l:language = ale#linter#GetLanguage(l:buffer, l:linter)
 
     AssertEqual a:expected_language, l:language
 endfunction
diff --git a/autoload/ale/c.vim b/autoload/ale/c.vim
index 39892d42..5cf4c690 100644
--- a/autoload/ale/c.vim
+++ b/autoload/ale/c.vim
@@ -8,6 +8,14 @@ let s:sep = has('win32') ? '\' : '/'
 " Set just so tests can override it.
 let g:__ale_c_project_filenames = ['.git/HEAD', 'configure', 'Makefile', 'CMakeLists.txt']
 
+function! s:CanParseMakefile(buffer) abort
+    " Something somewhere seems to delete this setting in tests, so ensure we
+    " always have a default value.
+    call ale#Set('c_parse_makefile', 0)
+
+    return ale#Var(a:buffer, 'c_parse_makefile')
+endfunction
+
 function! ale#c#GetBuildDirectory(buffer) abort
     let l:build_dir = ale#Var(a:buffer, 'c_build_dir')
 
@@ -61,10 +69,58 @@ function! ale#c#ShellSplit(line) abort
     return l:args
 endfunction
 
+" Takes the path prefix and a list of cflags and expands @file arguments to
+" the contents of the file.
+"
+" @file arguments are command line arguments recognised by gcc and clang. For
+" instance, if @./path/to/file was given to gcc, it would load .path/to/file
+" and use the contents of that file as arguments.
+function! ale#c#ExpandAtArgs(path_prefix, raw_split_lines) abort
+    let l:out_lines = []
+
+    for l:option in a:raw_split_lines
+        if stridx(l:option, '@') == 0
+            " This is an argument specifying a location of a file containing other arguments
+            let l:path = join(split(l:option, '\zs')[1:], '')
+
+            " Make path absolute
+            if stridx(l:path, s:sep) != 0 && stridx(l:path, '/') != 0
+                let l:rel_path = substitute(l:path, '"', '', 'g')
+                let l:rel_path = substitute(l:rel_path, '''', '', 'g')
+                let l:path = a:path_prefix . s:sep . l:rel_path
+            endif
+
+            " Read the file and add all the arguments
+            try
+                let l:additional_args = readfile(l:path)
+            catch
+                continue " All we can really do is skip this argument
+            endtry
+
+            let l:file_lines = []
+
+            for l:line in l:additional_args
+                let l:file_lines += ale#c#ShellSplit(l:line)
+            endfor
+
+            " @file arguments can include other @file arguments, so we must
+            " recurse.
+            let l:out_lines += ale#c#ExpandAtArgs(a:path_prefix, l:file_lines)
+        else
+            " This is not an @file argument, so don't touch it.
+            let l:out_lines += [l:option]
+        endif
+    endfor
+
+    return l:out_lines
+endfunction
+
 function! ale#c#ParseCFlags(path_prefix, cflag_line) abort
     let l:cflags_list = []
 
-    let l:split_lines = ale#c#ShellSplit(a:cflag_line)
+    let l:raw_split_lines = ale#c#ShellSplit(a:cflag_line)
+    " Expand @file arguments now before parsing
+    let l:split_lines = ale#c#ExpandAtArgs(a:path_prefix, l:raw_split_lines)
     let l:option_index = 0
 
     while l:option_index < len(l:split_lines)
@@ -76,6 +132,7 @@ function! ale#c#ParseCFlags(path_prefix, cflag_line) abort
         \ || stridx(l:option, '-iquote') == 0
         \ || stridx(l:option, '-isystem') == 0
         \ || stridx(l:option, '-idirafter') == 0
+        \ || stridx(l:option, '-iframework') == 0
             if stridx(l:option, '-I') == 0 && l:option isnot# '-I'
                 let l:arg = join(split(l:option, '\zs')[2:], '')
                 let l:option = '-I'
@@ -111,7 +168,7 @@ function! ale#c#ParseCFlags(path_prefix, cflag_line) abort
         elseif (stridx(l:option, '-W') == 0 && stridx(l:option, '-Wa,') != 0 && stridx(l:option, '-Wl,') != 0 && stridx(l:option, '-Wp,') != 0)
         \ || l:option is# '-w' || stridx(l:option, '-pedantic') == 0
         \ || l:option is# '-ansi' || stridx(l:option, '-std=') == 0
-        \ || (stridx(l:option, '-f') == 0 && stridx(l:option, '-fdump') != 0 && stridx(l:option, '-fdiagnostics') != 0 && stridx(l:option, '-fno-show-column') != 0)
+        \ || stridx(l:option, '-f') == 0 && l:option !~# '\v^-f(dump|diagnostics|no-show-column|stack-usage)'
         \ || stridx(l:option, '-O') == 0
         \ || l:option is# '-C' || l:option is# '-CC' || l:option is# '-trigraphs'
         \ || stridx(l:option, '-nostdinc') == 0 || stridx(l:option, '-iplugindir=') == 0
@@ -125,7 +182,7 @@ function! ale#c#ParseCFlags(path_prefix, cflag_line) abort
 endfunction
 
 function! ale#c#ParseCFlagsFromMakeOutput(buffer, make_output) abort
-    if !g:ale_c_parse_makefile
+    if !s:CanParseMakefile(a:buffer)
         return v:null
     endif
 
@@ -335,9 +392,7 @@ function! ale#c#GetCFlags(buffer, output) abort
         endif
     endif
 
-    if ale#Var(a:buffer, 'c_parse_makefile')
-    \&& !empty(a:output)
-    \&& !empty(l:cflags)
+    if s:CanParseMakefile(a:buffer) && !empty(a:output) && !empty(l:cflags)
         let l:cflags = ale#c#ParseCFlagsFromMakeOutput(a:buffer, a:output)
     endif
 
@@ -349,7 +404,7 @@ function! ale#c#GetCFlags(buffer, output) abort
 endfunction
 
 function! ale#c#GetMakeCommand(buffer) abort
-    if ale#Var(a:buffer, 'c_parse_makefile')
+    if s:CanParseMakefile(a:buffer)
         let l:makefile_path = ale#path#FindNearestFile(a:buffer, 'Makefile')
 
         if !empty(l:makefile_path)
diff --git a/autoload/ale/definition.vim b/autoload/ale/definition.vim
index ffcd9d10..0c1fb7cf 100644
--- a/autoload/ale/definition.vim
+++ b/autoload/ale/definition.vim
@@ -135,10 +135,6 @@ function! s:GoToLSPDefinition(linter, options, capability) abort
 endfunction
 
 function! ale#definition#GoTo(options) abort
-    if !get(g:, 'ale_ignore_2_7_warnings') && has_key(a:options, 'deprecated_command')
-        execute 'echom '':' . a:options.deprecated_command . ' is deprecated. Use `let g:ale_ignore_2_7_warnings = 1` to disable this message.'''
-    endif
-
     for l:linter in ale#linter#Get(&filetype)
         if !empty(l:linter.lsp)
             call s:GoToLSPDefinition(l:linter, a:options, 'definition')
@@ -147,10 +143,6 @@ function! ale#definition#GoTo(options) abort
 endfunction
 
 function! ale#definition#GoToType(options) abort
-    if !get(g:, 'ale_ignore_2_7_warnings') && has_key(a:options, 'deprecated_command')
-        execute 'echom '':' . a:options.deprecated_command . ' is deprecated. Use `let g:ale_ignore_2_7_warnings = 1` to disable this message.'''
-    endif
-
     for l:linter in ale#linter#Get(&filetype)
         if !empty(l:linter.lsp)
             " TODO: handle typeDefinition for tsserver if supported by the
diff --git a/autoload/ale/engine.vim b/autoload/ale/engine.vim
index 491d3c2e..cfc1e5d7 100644
--- a/autoload/ale/engine.vim
+++ b/autoload/ale/engine.vim
@@ -104,42 +104,6 @@ function! ale#engine#IsCheckingBuffer(buffer) abort
     \   || !empty(get(l:info, 'active_other_sources_list', []))
 endfunction
 
-" Register a temporary file to be managed with the ALE engine for
-" a current job run.
-function! ale#engine#ManageFile(buffer, filename) abort
-    if !get(g:, 'ale_ignore_2_4_warnings')
-        execute 'echom ''ale#engine#ManageFile is deprecated. Use `let g:ale_ignore_2_4_warnings = 1` to disable this message.'''
-    endif
-
-    call ale#command#ManageFile(a:buffer, a:filename)
-endfunction
-
-" Same as the above, but manage an entire directory.
-function! ale#engine#ManageDirectory(buffer, directory) abort
-    if !get(g:, 'ale_ignore_2_4_warnings')
-        execute 'echom ''ale#engine#ManageDirectory is deprecated. Use `let g:ale_ignore_2_4_warnings = 1` to disable this message.'''
-    endif
-
-    call ale#command#ManageDirectory(a:buffer, a:directory)
-endfunction
-
-function! ale#engine#CreateFile(buffer) abort
-    if !get(g:, 'ale_ignore_2_4_warnings')
-        execute 'echom ''ale#engine#CreateFile is deprecated. Use `let g:ale_ignore_2_4_warnings = 1` to disable this message.'''
-    endif
-
-    return ale#command#CreateFile(a:buffer)
-endfunction
-
-" Create a new temporary directory and manage it in one go.
-function! ale#engine#CreateDirectory(buffer) abort
-    if !get(g:, 'ale_ignore_2_4_warnings')
-        execute 'echom ''ale#engine#CreateDirectory is deprecated. Use `let g:ale_ignore_2_4_warnings = 1` to disable this message.'''
-    endif
-
-    return ale#command#CreateDirectory(a:buffer)
-endfunction
-
 function! ale#engine#HandleLoclist(linter_name, buffer, loclist, from_other_source) abort
     let l:info = get(g:ale_buffer_info, a:buffer, {})
 
@@ -192,7 +156,6 @@ function! s:HandleExit(job_info, buffer, output, data) abort
 
     let l:linter = a:job_info.linter
     let l:executable = a:job_info.executable
-    let l:next_chain_index = a:job_info.next_chain_index
 
     " Remove this job from the list.
     call ale#engine#MarkLinterInactive(l:buffer_info, l:linter.name)
@@ -207,20 +170,6 @@ function! s:HandleExit(job_info, buffer, output, data) abort
         call remove(a:output, -1)
     endif
 
-    if l:next_chain_index < len(get(l:linter, 'command_chain', []))
-        let [l:command, l:options] = ale#engine#ProcessChain(
-        \   a:buffer,
-        \   l:executable,
-        \   l:linter,
-        \   l:next_chain_index,
-        \   a:output,
-        \)
-
-        call s:RunJob(l:command, l:options)
-
-        return
-    endif
-
     try
         let l:loclist = ale#util#GetFunction(l:linter.callback)(a:buffer, a:output)
     " Handle the function being unknown, or being deleted.
@@ -454,20 +403,18 @@ function! s:RunJob(command, options) abort
     let l:buffer = a:options.buffer
     let l:linter = a:options.linter
     let l:output_stream = a:options.output_stream
-    let l:next_chain_index = a:options.next_chain_index
     let l:read_buffer = a:options.read_buffer
     let l:info = g:ale_buffer_info[l:buffer]
 
     let l:Callback = function('s:HandleExit', [{
     \   'linter': l:linter,
     \   'executable': l:executable,
-    \   'next_chain_index': l:next_chain_index,
     \}])
     let l:result = ale#command#Run(l:buffer, l:command, l:Callback, {
     \   'output_stream': l:output_stream,
     \   'executable': l:executable,
     \   'read_buffer': l:read_buffer,
-    \   'log_output': l:next_chain_index >= len(get(l:linter, 'command_chain', [])),
+    \   'log_output': 1,
     \})
 
     " Only proceed if the job is being run.
@@ -482,68 +429,6 @@ function! s:RunJob(command, options) abort
     return 1
 endfunction
 
-" Determine which commands to run for a link in a command chain, or
-" just a regular command.
-function! ale#engine#ProcessChain(buffer, executable, linter, chain_index, input) abort
-    let l:output_stream = get(a:linter, 'output_stream', 'stdout')
-    let l:read_buffer = a:linter.read_buffer
-    let l:chain_index = a:chain_index
-    let l:input = a:input
-
-    while l:chain_index < len(a:linter.command_chain)
-        " Run a chain of commands, one asynchronous command after the other,
-        " so that many programs can be run in a sequence.
-        let l:chain_item = a:linter.command_chain[l:chain_index]
-
-        if l:chain_index == 0
-            " The first callback in the chain takes only a buffer number.
-            let l:command = ale#util#GetFunction(l:chain_item.callback)(
-            \   a:buffer
-            \)
-        else
-            " The second callback in the chain takes some input too.
-            let l:command = ale#util#GetFunction(l:chain_item.callback)(
-            \   a:buffer,
-            \   l:input
-            \)
-        endif
-
-        " If we have a command to run, execute that.
-        if !empty(l:command)
-            " The chain item can override the output_stream option.
-            if has_key(l:chain_item, 'output_stream')
-                let l:output_stream = l:chain_item.output_stream
-            endif
-
-            " The chain item can override the read_buffer option.
-            if has_key(l:chain_item, 'read_buffer')
-                let l:read_buffer = l:chain_item.read_buffer
-            elseif l:chain_index != len(a:linter.command_chain) - 1
-                " Don't read the buffer for commands besides the last one
-                " in the chain by default.
-                let l:read_buffer = 0
-            endif
-
-            break
-        endif
-
-        " Command chain items can return an empty string to indicate that
-        " a command should be skipped, so we should try the next item
-        " with no input.
-        let l:input = []
-        let l:chain_index += 1
-    endwhile
-
-    return [l:command, {
-    \   'executable': a:executable,
-    \   'buffer': a:buffer,
-    \   'linter': a:linter,
-    \   'output_stream': l:output_stream,
-    \   'next_chain_index': l:chain_index + 1,
-    \   'read_buffer': l:read_buffer,
-    \}]
-endfunction
-
 function! s:StopCurrentJobs(buffer, clear_lint_file_jobs) abort
     let l:info = get(g:ale_buffer_info, a:buffer, {})
     call ale#command#StopJobs(a:buffer, 'linter')
@@ -622,25 +507,12 @@ function! s:RunIfExecutable(buffer, linter, executable) abort
         let l:job_type = a:linter.lint_file ? 'file_linter' : 'linter'
         call setbufvar(a:buffer, 'ale_job_type', l:job_type)
 
-        if has_key(a:linter, 'command_chain')
-            let [l:command, l:options] = ale#engine#ProcessChain(
-            \   a:buffer,
-            \   a:executable,
-            \   a:linter,
-            \   0,
-            \   []
-            \)
-
-            return s:RunJob(l:command, l:options)
-        endif
-
         let l:command = ale#linter#GetCommand(a:buffer, a:linter)
         let l:options = {
         \   'executable': a:executable,
         \   'buffer': a:buffer,
         \   'linter': a:linter,
         \   'output_stream': get(a:linter, 'output_stream', 'stdout'),
-        \   'next_chain_index': 1,
         \   'read_buffer': a:linter.read_buffer,
         \}
 
diff --git a/autoload/ale/fix.vim b/autoload/ale/fix.vim
index 69817b36..b2a39444 100644
--- a/autoload/ale/fix.vim
+++ b/autoload/ale/fix.vim
@@ -90,7 +90,6 @@ function! s:HandleExit(job_info, buffer, job_output, data) abort
         let l:output = a:job_output
     endif
 
-    let l:ChainCallback = get(a:job_info, 'chain_with', v:null)
     let l:ProcessWith = get(a:job_info, 'process_with', v:null)
 
     " Post-process the output with a function if we have one.
@@ -102,27 +101,18 @@ function! s:HandleExit(job_info, buffer, job_output, data) abort
     " otherwise skip this job and use the input from before.
     "
     " We'll use the input from before for chained commands.
-    if l:ChainCallback is v:null && !empty(split(join(l:output)))
+    if !empty(split(join(l:output)))
         let l:input = l:output
     else
         let l:input = a:job_info.input
     endif
 
-    if l:ChainCallback isnot v:null && !get(g:, 'ale_ignore_2_4_warnings')
-        execute 'echom ''chain_with is deprecated. Use `let g:ale_ignore_2_4_warnings = 1` to disable this message.'''
-    endif
-
-    let l:next_index = l:ChainCallback is v:null
-    \   ? a:job_info.callback_index + 1
-    \   : a:job_info.callback_index
-
     call s:RunFixer({
     \   'buffer': a:buffer,
     \   'input': l:input,
     \   'output': l:output,
     \   'callback_list': a:job_info.callback_list,
-    \   'callback_index': l:next_index,
-    \   'chain_callback': l:ChainCallback,
+    \   'callback_index': a:job_info.callback_index + 1,
     \})
 endfunction
 
@@ -152,17 +142,14 @@ function! s:RunJob(result, options) abort
     endif
 
     let l:command = get(a:result, 'command', '')
-    let l:ChainWith = get(a:result, 'chain_with', v:null)
 
     if empty(l:command)
-        " If the command is empty, skip to the next item, or call the
-        " chain_with function.
+        " If the command is empty, skip to the next item.
         call s:RunFixer({
         \   'buffer': l:buffer,
         \   'input': l:input,
-        \   'callback_index': a:options.callback_index + (l:ChainWith is v:null),
+        \   'callback_index': a:options.callback_index,
         \   'callback_list': a:options.callback_list,
-        \   'chain_callback': l:ChainWith,
         \   'output': [],
         \})
 
@@ -170,8 +157,7 @@ function! s:RunJob(result, options) abort
     endif
 
     let l:read_temporary_file = get(a:result, 'read_temporary_file', 0)
-    " Default to piping the buffer for the last fixer in the chain.
-    let l:read_buffer = get(a:result, 'read_buffer', l:ChainWith is v:null)
+    let l:read_buffer = get(a:result, 'read_buffer', 1)
     let l:output_stream = get(a:result, 'output_stream', 'stdout')
 
     if l:read_temporary_file
@@ -180,7 +166,6 @@ function! s:RunJob(result, options) abort
 
     let l:Callback = function('s:HandleExit', [{
     \   'input': l:input,
-    \   'chain_with': l:ChainWith,
     \   'callback_index': a:options.callback_index,
     \   'callback_list': a:options.callback_list,
     \   'process_with': get(a:result, 'process_with', v:null),
diff --git a/autoload/ale/fix/registry.vim b/autoload/ale/fix/registry.vim
index 02b02699..94476ca9 100644
--- a/autoload/ale/fix/registry.vim
+++ b/autoload/ale/fix/registry.vim
@@ -365,6 +365,11 @@ let s:default_registry = {
 \       'suggested_filetypes': ['nix'],
 \       'description': 'A formatter for Nix code',
 \   },
+\   'remark-lint': {
+\       'function': 'ale#fixers#remark_lint#Fix',
+\       'suggested_filetypes': ['markdown'],
+\       'description': 'Fix markdown files with remark-lint',
+\   },
 \   'html-beautify': {
 \       'function': 'ale#fixers#html_beautify#Fix',
 \       'suggested_filetypes': ['html', 'htmldjango'],
diff --git a/autoload/ale/fixers/remark_lint.vim b/autoload/ale/fixers/remark_lint.vim
new file mode 100644
index 00000000..3ce442f3
--- /dev/null
+++ b/autoload/ale/fixers/remark_lint.vim
@@ -0,0 +1,24 @@
+" Author: blyoa <blyoa110@gmail.com>
+" Description: Fixing files with remark-lint.
+
+call ale#Set('markdown_remark_lint_executable', 'remark')
+call ale#Set('markdown_remark_lint_use_global', get(g:, 'ale_use_global_executables', 0))
+call ale#Set('markdown_remark_lint_options', '')
+
+function! ale#fixers#remark_lint#GetExecutable(buffer) abort
+    return ale#node#FindExecutable(a:buffer, 'markdown_remark_lint', [
+    \   'node_modules/remark-cli/cli.js',
+    \   'node_modules/.bin/remark',
+    \])
+endfunction
+
+function! ale#fixers#remark_lint#Fix(buffer) abort
+    let l:executable = ale#fixers#remark_lint#GetExecutable(a:buffer)
+    let l:options = ale#Var(a:buffer, 'markdown_remark_lint_options')
+
+    return {
+    \   'command': ale#Escape(l:executable)
+    \       . (!empty(l:options) ? ' ' . l:options : ''),
+    \}
+endfunction
+
diff --git a/autoload/ale/fixers/standard.vim b/autoload/ale/fixers/standard.vim
index cffa9f9d..46decebf 100644
--- a/autoload/ale/fixers/standard.vim
+++ b/autoload/ale/fixers/standard.vim
@@ -27,7 +27,7 @@ function! ale#fixers#standard#Fix(buffer) abort
     return {
     \   'command': ale#node#Executable(a:buffer, l:executable)
     \   . (!empty(l:options) ? ' ' . l:options : '')
-    \       . ' --fix %t',
+    \       . ' --fix --stdin < %s > %t',
     \   'read_temporary_file': 1,
     \}
 endfunction
diff --git a/autoload/ale/handlers/sh.vim b/autoload/ale/handlers/sh.vim
index 75eaf71f..1e50cb89 100644
--- a/autoload/ale/handlers/sh.vim
+++ b/autoload/ale/handlers/sh.vim
@@ -4,17 +4,24 @@
 function! ale#handlers#sh#GetShellType(buffer) abort
     let l:bang_line = get(getbufline(a:buffer, 1), 0, '')
 
+    let l:command = ''
+
     " Take the shell executable from the hashbang, if we can.
     if l:bang_line[:1] is# '#!'
         " Remove options like -e, etc.
         let l:command = substitute(l:bang_line, ' --\?[a-zA-Z0-9]\+', '', 'g')
-
-        for l:possible_shell in ['bash', 'dash', 'ash', 'tcsh', 'csh', 'zsh', 'ksh', 'sh']
-            if l:command =~# l:possible_shell . '\s*$'
-                return l:possible_shell
-            endif
-        endfor
     endif
 
+    " If we couldn't find a hashbang, try the filetype
+    if l:command is# ''
+        let l:command = &filetype
+    endif
+
+    for l:possible_shell in ['bash', 'dash', 'ash', 'tcsh', 'csh', 'zsh', 'ksh', 'sh']
+        if l:command =~# l:possible_shell . '\s*$'
+            return l:possible_shell
+        endif
+    endfor
+
     return ''
 endfunction
diff --git a/autoload/ale/hover.vim b/autoload/ale/hover.vim
index 168ff424..38b4b866 100644
--- a/autoload/ale/hover.vim
+++ b/autoload/ale/hover.vim
@@ -264,7 +264,10 @@ function! s:OnReady(line, column, opt, linter, lsp_details) abort
         " hover position probably won't make sense.
         call ale#lsp#NotifyForChanges(l:id, l:buffer)
 
-        let l:column = min([a:column, len(getbufline(l:buffer, a:line)[0])])
+        let l:column = max([
+        \   min([a:column, len(getbufline(l:buffer, a:line)[0])]),
+        \   1,
+        \])
 
         let l:message = ale#lsp#message#Hover(l:buffer, a:line, l:column)
     endif
diff --git a/autoload/ale/linter.vim b/autoload/ale/linter.vim
index 0e935149..fecfeed6 100644
--- a/autoload/ale/linter.vim
+++ b/autoload/ale/linter.vim
@@ -77,10 +77,6 @@ function! s:IsBoolean(value) abort
     return type(a:value) is v:t_number && (a:value == 0 || a:value == 1)
 endfunction
 
-function! s:LanguageGetter(buffer) dict abort
-    return l:self.language
-endfunction
-
 function! ale#linter#PreProcess(filetype, linter) abort
     if type(a:linter) isnot v:t_dict
         throw 'The linter object must be a Dictionary'
@@ -114,14 +110,7 @@ function! ale#linter#PreProcess(filetype, linter) abort
 
     if !l:needs_executable
         if has_key(a:linter, 'executable')
-        \|| has_key(a:linter, 'executable_callback')
-            throw '`executable` and `executable_callback` cannot be used when lsp == ''socket'''
-        endif
-    elseif has_key(a:linter, 'executable_callback')
-        let l:obj.executable_callback = a:linter.executable_callback
-
-        if !s:IsCallback(l:obj.executable_callback)
-            throw '`executable_callback` must be a callback if defined'
+            throw '`executable` cannot be used when lsp == ''socket'''
         endif
     elseif has_key(a:linter, 'executable')
         let l:obj.executable = a:linter.executable
@@ -131,54 +120,12 @@ function! ale#linter#PreProcess(filetype, linter) abort
             throw '`executable` must be a String or Function if defined'
         endif
     else
-        throw 'Either `executable` or `executable_callback` must be defined'
+        throw '`executable` must be defined'
     endif
 
     if !l:needs_command
         if has_key(a:linter, 'command')
-        \|| has_key(a:linter, 'command_callback')
-        \|| has_key(a:linter, 'command_chain')
-            throw '`command` and `command_callback` and `command_chain` cannot be used when lsp == ''socket'''
-        endif
-    elseif has_key(a:linter, 'command_chain')
-        let l:obj.command_chain = a:linter.command_chain
-
-        if type(l:obj.command_chain) isnot v:t_list
-            throw '`command_chain` must be a List'
-        endif
-
-        if empty(l:obj.command_chain)
-            throw '`command_chain` must contain at least one item'
-        endif
-
-        let l:link_index = 0
-
-        for l:link in l:obj.command_chain
-            let l:err_prefix = 'The `command_chain` item ' . l:link_index . ' '
-
-            if !s:IsCallback(get(l:link, 'callback'))
-                throw l:err_prefix . 'must define a `callback` function'
-            endif
-
-            if has_key(l:link, 'output_stream')
-                if type(l:link.output_stream) isnot v:t_string
-                \|| index(['stdout', 'stderr', 'both'], l:link.output_stream) < 0
-                    throw l:err_prefix . '`output_stream` flag must be '
-                    \   . "'stdout', 'stderr', or 'both'"
-                endif
-            endif
-
-            if has_key(l:link, 'read_buffer') && !s:IsBoolean(l:link.read_buffer)
-                throw l:err_prefix . 'value for `read_buffer` must be `0` or `1`'
-            endif
-
-            let l:link_index += 1
-        endfor
-    elseif has_key(a:linter, 'command_callback')
-        let l:obj.command_callback = a:linter.command_callback
-
-        if !s:IsCallback(l:obj.command_callback)
-            throw '`command_callback` must be a callback if defined'
+            throw '`command` cannot be used when lsp == ''socket'''
         endif
     elseif has_key(a:linter, 'command')
         let l:obj.command = a:linter.command
@@ -188,22 +135,12 @@ function! ale#linter#PreProcess(filetype, linter) abort
             throw '`command` must be a String or Function if defined'
         endif
     else
-        throw 'Either `command`, `executable_callback`, `command_chain` '
-        \   . 'must be defined'
-    endif
-
-    if (
-    \   has_key(a:linter, 'command')
-    \   + has_key(a:linter, 'command_chain')
-    \   + has_key(a:linter, 'command_callback')
-    \) > 1
-        throw 'Only one of `command`, `command_callback`, or `command_chain` '
-        \   . 'should be set'
+        throw '`command` must be defined'
     endif
 
     if !l:needs_address
-        if has_key(a:linter, 'address') || has_key(a:linter, 'address_callback')
-            throw '`address` or `address_callback` cannot be used when lsp != ''socket'''
+        if has_key(a:linter, 'address')
+            throw '`address` cannot be used when lsp != ''socket'''
         endif
     elseif has_key(a:linter, 'address')
         if type(a:linter.address) isnot v:t_string
@@ -212,41 +149,17 @@ function! ale#linter#PreProcess(filetype, linter) abort
         endif
 
         let l:obj.address = a:linter.address
-    elseif has_key(a:linter, 'address_callback')
-        let l:obj.address_callback = a:linter.address_callback
-
-        if !s:IsCallback(l:obj.address_callback)
-            throw '`address_callback` must be a callback if defined'
-        endif
     else
-        throw '`address` or `address_callback` must be defined for getting the LSP address'
+        throw '`address` must be defined for getting the LSP address'
     endif
 
     if l:needs_lsp_details
-        if has_key(a:linter, 'language_callback')
-            if has_key(a:linter, 'language')
-                throw 'Only one of `language` or `language_callback` '
-                \   . 'should be set'
-            endif
+        " Default to using the filetype as the language.
+        let l:obj.language = get(a:linter, 'language', a:filetype)
 
-            let l:obj.language_callback = get(a:linter, 'language_callback')
-
-            if !s:IsCallback(l:obj.language_callback)
-                throw '`language_callback` must be a callback for LSP linters'
-            endif
-        else
-            " Default to using the filetype as the language.
-            let l:Language = get(a:linter, 'language', a:filetype)
-
-            if type(l:Language) is v:t_string
-                " Make 'language_callback' return the 'language' value.
-                let l:obj.language = l:Language
-                let l:obj.language_callback = function('s:LanguageGetter')
-            elseif type(l:Language) is v:t_func
-                let l:obj.language_callback = l:Language
-            else
-                throw '`language` must be a String or Funcref'
-            endif
+        if type(l:obj.language) isnot v:t_string
+        \&& type(l:obj.language) isnot v:t_func
+            throw '`language` must be a String or Funcref if defined'
         endif
 
         if has_key(a:linter, 'project_root')
@@ -254,16 +167,10 @@ function! ale#linter#PreProcess(filetype, linter) abort
 
             if type(l:obj.project_root) isnot v:t_string
             \&& type(l:obj.project_root) isnot v:t_func
-                throw '`project_root` must be a String or Function if defined'
-            endif
-        elseif has_key(a:linter, 'project_root_callback')
-            let l:obj.project_root_callback = a:linter.project_root_callback
-
-            if !s:IsCallback(l:obj.project_root_callback)
-                throw '`project_root_callback` must be a callback if defined'
+                throw '`project_root` must be a String or Function'
             endif
         else
-            throw '`project_root` or `project_root_callback` must be defined for LSP linters'
+            throw '`project_root` must be defined for LSP linters'
         endif
 
         if has_key(a:linter, 'completion_filter')
@@ -274,37 +181,16 @@ function! ale#linter#PreProcess(filetype, linter) abort
             endif
         endif
 
-        if has_key(a:linter, 'initialization_options_callback')
-            if has_key(a:linter, 'initialization_options')
-                throw 'Only one of `initialization_options` or '
-                \   . '`initialization_options_callback` should be set'
-            endif
-
-            let l:obj.initialization_options_callback = a:linter.initialization_options_callback
-
-            if !s:IsCallback(l:obj.initialization_options_callback)
-                throw '`initialization_options_callback` must be a callback if defined'
-            endif
-        elseif has_key(a:linter, 'initialization_options')
+        if has_key(a:linter, 'initialization_options')
             let l:obj.initialization_options = a:linter.initialization_options
 
             if type(l:obj.initialization_options) isnot v:t_dict
             \&& type(l:obj.initialization_options) isnot v:t_func
-                throw '`initialization_options` must be a String or Function if defined'
+                throw '`initialization_options` must be a Dictionary or Function if defined'
             endif
         endif
 
-        if has_key(a:linter, 'lsp_config_callback')
-            if has_key(a:linter, 'lsp_config')
-                throw 'Only one of `lsp_config` or `lsp_config_callback` should be set'
-            endif
-
-            let l:obj.lsp_config_callback = a:linter.lsp_config_callback
-
-            if !s:IsCallback(l:obj.lsp_config_callback)
-                throw '`lsp_config_callback` must be a callback if defined'
-            endif
-        elseif has_key(a:linter, 'lsp_config')
+        if has_key(a:linter, 'lsp_config')
             if type(a:linter.lsp_config) isnot v:t_dict
             \&& type(a:linter.lsp_config) isnot v:t_func
                 throw '`lsp_config` must be a Dictionary or Function if defined'
@@ -347,14 +233,6 @@ function! ale#linter#PreProcess(filetype, linter) abort
         throw '`aliases` must be a List of String values'
     endif
 
-    for l:key in filter(keys(a:linter), 'v:val[-9:] is# ''_callback'' || v:val is# ''command_chain''')
-        if !get(g:, 'ale_ignore_2_4_warnings')
-            execute 'echom l:key . '' is deprecated. Use `let g:ale_ignore_2_4_warnings = 1` to disable this message.'''
-        endif
-
-        break
-    endfor
-
     return l:obj
 endfunction
 
@@ -522,9 +400,7 @@ endfunction
 
 " Given a buffer and linter, get the executable String for the linter.
 function! ale#linter#GetExecutable(buffer, linter) abort
-    let l:Executable = has_key(a:linter, 'executable_callback')
-    \   ? function(a:linter.executable_callback)
-    \   : a:linter.executable
+    let l:Executable = a:linter.executable
 
     return type(l:Executable) is v:t_func
     \   ? l:Executable(a:buffer)
@@ -532,24 +408,21 @@ function! ale#linter#GetExecutable(buffer, linter) abort
 endfunction
 
 " Given a buffer and linter, get the command String for the linter.
-" The command_chain key is not supported.
 function! ale#linter#GetCommand(buffer, linter) abort
-    let l:Command = has_key(a:linter, 'command_callback')
-    \   ? function(a:linter.command_callback)
-    \   : a:linter.command
+    let l:Command = a:linter.command
 
-    return type(l:Command) is v:t_func
-    \   ? l:Command(a:buffer)
-    \   : l:Command
+    return type(l:Command) is v:t_func ? l:Command(a:buffer) : l:Command
 endfunction
 
 " Given a buffer and linter, get the address for connecting to the server.
 function! ale#linter#GetAddress(buffer, linter) abort
-    let l:Address = has_key(a:linter, 'address_callback')
-    \   ? function(a:linter.address_callback)
-    \   : a:linter.address
+    let l:Address = a:linter.address
 
-    return type(l:Address) is v:t_func
-    \   ? l:Address(a:buffer)
-    \   : l:Address
+    return type(l:Address) is v:t_func ? l:Address(a:buffer) : l:Address
+endfunction
+
+function! ale#linter#GetLanguage(buffer, linter) abort
+    let l:Language = a:linter.language
+
+    return type(l:Language) is v:t_func ? l:Language(a:buffer) : l:Language
 endfunction
diff --git a/autoload/ale/lsp.vim b/autoload/ale/lsp.vim
index ae8fd51d..7d99e9d2 100644
--- a/autoload/ale/lsp.vim
+++ b/autoload/ale/lsp.vim
@@ -64,6 +64,9 @@ endfunction
 
 " Used only in tests.
 function! ale#lsp#GetConnections() abort
+    " This command will throw from the sandbox.
+    let &l:equalprg=&l:equalprg
+
     return s:connections
 endfunction
 
@@ -449,6 +452,7 @@ function! ale#lsp#StartProgram(conn_id, executable, command) abort
     endif
 
     if l:started && !l:conn.is_tsserver
+        let l:conn.initialized = 0
         call s:SendInitMessage(l:conn)
     endif
 
diff --git a/autoload/ale/lsp_linter.vim b/autoload/ale/lsp_linter.vim
index e4148ceb..f4a42bf4 100644
--- a/autoload/ale/lsp_linter.vim
+++ b/autoload/ale/lsp_linter.vim
@@ -227,7 +227,7 @@ function! ale#lsp_linter#OnInit(linter, details, Callback) abort
     let l:command = a:details.command
 
     let l:config = ale#lsp_linter#GetConfig(l:buffer, a:linter)
-    let l:language_id = ale#util#GetFunction(a:linter.language_callback)(l:buffer)
+    let l:language_id = ale#linter#GetLanguage(l:buffer, a:linter)
 
     call ale#lsp#UpdateConfig(l:conn_id, l:buffer, l:config)
 
diff --git a/autoload/ale/test.vim b/autoload/ale/test.vim
index 082d91ff..6fcbf35e 100644
--- a/autoload/ale/test.vim
+++ b/autoload/ale/test.vim
@@ -145,8 +145,8 @@ function! ale#test#WaitForJobs(deadline) abort
     " end, but before handlers are run.
     sleep 10ms
 
-    " We must check the buffer data again to see if new jobs started
-    " for command_chain linters.
+    " We must check the buffer data again to see if new jobs started for
+    " linters with chained commands.
     let l:has_new_jobs = 0
 
     " Check again to see if any jobs are running.
diff --git a/doc/ale-c.txt b/doc/ale-c.txt
index fc0d941a..fe28cf4a 100644
--- a/doc/ale-c.txt
+++ b/doc/ale-c.txt
@@ -1,6 +1,9 @@
 ===============================================================================
 ALE C Integration                                               *ale-c-options*
 
+For basic checking of problems with C files, ALE offers the `cc` linter, which
+runs either `clang`, or `gcc`. See |ale-c-cc|.
+
 
 ===============================================================================
 Global Options
@@ -11,12 +14,12 @@ g:ale_c_build_dir_names                               *g:ale_c_build_dir_names*
   Type: |List|
   Default: `['build', 'bin']`
 
-  A list of directory names to be used when searching upwards from cpp
-  files to discover compilation databases with. For directory named `'foo'`,
-  ALE will search for `'foo/compile_commands.json'` in all directories on and above
-  the directory containing the cpp file to find path to compilation database.
-  This feature is useful for the clang tools wrapped around LibTooling (namely
-  here, clang-tidy)
+  A list of directory names to be used when searching upwards from cpp files
+  to discover compilation databases with. For directory named `'foo'`, ALE
+  will search for `'foo/compile_commands.json'` in all directories on and
+  above the directory containing the cpp file to find path to compilation
+  database.  This feature is useful for the clang tools wrapped around
+  LibTooling (namely here, clang-tidy)
 
 
 g:ale_c_build_dir                                           *g:ale_c_build_dir*
@@ -94,22 +97,58 @@ g:ale_c_astyle_project_options                 *g:ale_c_astyle_project_options*
 
 
 ===============================================================================
-clang                                                             *ale-c-clang*
+cc                                                                   *ale-c-cc*
+                                                                    *ale-c-gcc*
+                                                                  *ale-c-clang*
 
-g:ale_c_clang_executable                             *g:ale_c_clang_executable*
-                                                     *b:ale_c_clang_executable*
+g:ale_c_cc_executable                                   *g:ale_c_cc_executable*
+                                                        *b:ale_c_cc_executable*
   Type: |String|
-  Default: `'clang'`
+  Default: `'<auto>'`
 
-  This variable can be changed to use a different executable for clang.
+  This variable can be changed to use a different executable for a C compiler.
+
+  ALE will try to use `clang` if Clang is available, otherwise ALE will
+  default to checking C code with `gcc`.
 
 
-g:ale_c_clang_options                                   *g:ale_c_clang_options*
-                                                        *b:ale_c_clang_options*
+g:ale_c_cc_options                                         *g:ale_c_cc_options*
+                                                           *b:ale_c_cc_options*
   Type: |String|
   Default: `'-std=c11 -Wall'`
 
-  This variable can be changed to modify flags given to clang.
+  This variable can be change to modify flags given to the C compiler.
+
+
+===============================================================================
+ccls                                                               *ale-c-ccls*
+
+g:ale_c_ccls_executable                               *g:ale_c_ccls_executable*
+                                                      *b:ale_c_ccls_executable*
+  Type: |String|
+  Default: `'ccls'`
+
+  This variable can be changed to use a different executable for ccls.
+
+
+g:ale_c_ccls_init_options                           *g:ale_c_ccls_init_options*
+                                                    *b:ale_c_ccls_init_options*
+  Type: |Dictionary|
+  Default: `{}`
+
+  This variable can be changed to customize ccls initialization options.
+  Example: >
+      {
+    \   'cacheDirectory': '/tmp/ccls',
+    \   'cacheFormat': 'binary',
+    \   'diagnostics': {
+    \     'onOpen': 0,
+    \     'opChange': 1000,
+    \   },
+    \ }
+<
+  Visit https://github.com/MaskRay/ccls/wiki/Initialization-options for all
+  available options and explanations.
 
 
 ===============================================================================
@@ -294,25 +333,6 @@ g:ale_c_flawfinder_error_severity           *g:ale_c_flawfinder_error_severity*
   error.  This setting also applies to flawfinder for c++.
 
 
-===============================================================================
-gcc                                                                 *ale-c-gcc*
-
-g:ale_c_gcc_executable                                 *g:ale_c_gcc_executable*
-                                                       *b:ale_c_gcc_executable*
-  Type: |String|
-  Default: `'gcc'`
-
-  This variable can be changed to use a different executable for gcc.
-
-
-g:ale_c_gcc_options                                       *g:ale_c_gcc_options*
-                                                          *b:ale_c_gcc_options*
-  Type: |String|
-  Default: `'-std=c11 -Wall'`
-
-  This variable can be change to modify flags given to gcc.
-
-
 ===============================================================================
 uncrustify                                                   *ale-c-uncrustify*
 
@@ -332,36 +352,5 @@ g:ale_c_uncrustify_options                         *g:ale_c_uncrustify_options*
   This variable can be change to modify flags given to uncrustify.
 
 
-===============================================================================
-ccls                                                               *ale-c-ccls*
-
-g:ale_c_ccls_executable                               *g:ale_c_ccls_executable*
-                                                      *b:ale_c_ccls_executable*
-  Type: |String|
-  Default: `'ccls'`
-
-  This variable can be changed to use a different executable for ccls.
-
-
-g:ale_c_ccls_init_options                           *g:ale_c_ccls_init_options*
-                                                    *b:ale_c_ccls_init_options*
-  Type: |Dictionary|
-  Default: `{}`
-
-  This variable can be changed to customize ccls initialization options.
-  Example: >
-      {
-    \   'cacheDirectory': '/tmp/ccls',
-    \   'cacheFormat': 'binary',
-    \   'diagnostics': {
-    \     'onOpen': 0,
-    \     'opChange': 1000,
-    \   },
-    \ }
-<
-  Visit https://github.com/MaskRay/ccls/wiki/Initialization-options for all
-  available options and explanations.
-
-
 ===============================================================================
   vim:tw=78:ts=2:sts=2:sw=2:ft=help:norl:
diff --git a/doc/ale-cpp.txt b/doc/ale-cpp.txt
index fbe31370..651b4160 100644
--- a/doc/ale-cpp.txt
+++ b/doc/ale-cpp.txt
@@ -1,6 +1,9 @@
 ===============================================================================
 ALE C++ Integration                                           *ale-cpp-options*
 
+For basic checking of problems with C++ files, ALE offers the `cc` linter,
+which runs either `clang++`, or `gcc`. See |ale-cpp-cc|.
+
 
 ===============================================================================
 Global Options
@@ -38,41 +41,58 @@ g:ale_cpp_astyle_project_options             *g:ale_cpp_astyle_project_options*
 
 
 ===============================================================================
-clang                                                           *ale-cpp-clang*
+cc                                                                 *ale-cpp-cc*
+                                                                  *ale-cpp-gcc*
+                                                                *ale-cpp-clang*
 
-g:ale_cpp_clang_executable                         *g:ale_cpp_clang_executable*
-                                                   *b:ale_cpp_clang_executable*
+g:ale_cpp_cc_executable                               *g:ale_cpp_cc_executable*
+                                                      *b:ale_cpp_cc_executable*
   Type: |String|
-  Default: `'clang++'`
+  Default: `'<auto>'`
 
-  This variable can be changed to use a different executable for clang.
+  This variable can be changed to use a different executable for a C++ compiler.
+
+  ALE will try to use `clang++` if Clang is available, otherwise ALE will
+  default to checking C++ code with `gcc`.
 
 
-g:ale_cpp_clang_options                               *g:ale_cpp_clang_options*
-                                                      *b:ale_cpp_clang_options*
+g:ale_cpp_cc_options                                     *g:ale_cpp_cc_options*
+                                                         *b:ale_cpp_cc_options*
   Type: |String|
   Default: `'-std=c++14 -Wall'`
 
-  This variable can be changed to modify flags given to clang.
+  This variable can be change to modify flags given to the C++ compiler.
 
 
 ===============================================================================
-clangd                                                         *ale-cpp-clangd*
+ccls                                                             *ale-cpp-ccls*
 
-g:ale_cpp_clangd_executable                       *g:ale_cpp_clangd_executable*
-                                                  *b:ale_cpp_clangd_executable*
+g:ale_cpp_ccls_executable                           *g:ale_cpp_ccls_executable*
+                                                    *b:ale_cpp_ccls_executable*
   Type: |String|
-  Default: `'clangd'`
+  Default: `'ccls'`
 
-  This variable can be changed to use a different executable for clangd.
+  This variable can be changed to use a different executable for ccls.
 
 
-g:ale_cpp_clangd_options                             *g:ale_cpp_clangd_options*
-                                                     *b:ale_cpp_clangd_options*
-  Type: |String|
-  Default: `''`
+g:ale_cpp_ccls_init_options                       *g:ale_cpp_ccls_init_options*
+                                                  *b:ale_cpp_ccls_init_options*
+  Type: |Dictionary|
+  Default: `{}`
 
-  This variable can be changed to modify flags given to clangd.
+  This variable can be changed to customize ccls initialization options.
+  Example: >
+      {
+    \   'cacheDirectory': '/tmp/ccls',
+    \   'cacheFormat': 'binary',
+    \   'diagnostics': {
+    \     'onOpen': 0,
+    \     'opChange': 1000,
+    \   },
+    \ }
+<
+  Visit https://github.com/MaskRay/ccls/wiki/Initialization-options for all
+  available options and explanations.
 
 
 ===============================================================================
@@ -106,6 +126,25 @@ g:ale_cpp_clangcheck_options                     *g:ale_cpp_clangcheck_options*
   option.
 
 
+===============================================================================
+clangd                                                         *ale-cpp-clangd*
+
+g:ale_cpp_clangd_executable                       *g:ale_cpp_clangd_executable*
+                                                  *b:ale_cpp_clangd_executable*
+  Type: |String|
+  Default: `'clangd'`
+
+  This variable can be changed to use a different executable for clangd.
+
+
+g:ale_cpp_clangd_options                             *g:ale_cpp_clangd_options*
+                                                     *b:ale_cpp_clangd_options*
+  Type: |String|
+  Default: `''`
+
+  This variable can be changed to modify flags given to clangd.
+
+
 ===============================================================================
 clang-format                                              *ale-cpp-clangformat*
 
@@ -295,61 +334,11 @@ g:ale_cpp_flawfinder_options                             *g:ale-cpp-flawfinder*
   This variable can be used to pass extra options into the flawfinder command.
 
 
-===============================================================================
-gcc                                                               *ale-cpp-gcc*
-
-g:ale_cpp_gcc_executable                             *g:ale_cpp_gcc_executable*
-                                                     *b:ale_cpp_gcc_executable*
-  Type: |String|
-  Default: `'gcc'`
-
-  This variable can be changed to use a different executable for gcc.
-
-
-g:ale_cpp_gcc_options                                   *g:ale_cpp_gcc_options*
-                                                        *b:ale_cpp_gcc_options*
-  Type: |String|
-  Default: `'-std=c++14 -Wall'`
-
-  This variable can be changed to modify flags given to gcc.
-
-
 ===============================================================================
 uncrustify                                                 *ale-cpp-uncrustify*
 
 See |ale-c-uncrustify| for information about the available options.
 
 
-===============================================================================
-ccls                                                             *ale-cpp-ccls*
-
-g:ale_cpp_ccls_executable                           *g:ale_cpp_ccls_executable*
-                                                    *b:ale_cpp_ccls_executable*
-  Type: |String|
-  Default: `'ccls'`
-
-  This variable can be changed to use a different executable for ccls.
-
-
-g:ale_cpp_ccls_init_options                       *g:ale_cpp_ccls_init_options*
-                                                  *b:ale_cpp_ccls_init_options*
-  Type: |Dictionary|
-  Default: `{}`
-
-  This variable can be changed to customize ccls initialization options.
-  Example: >
-      {
-    \   'cacheDirectory': '/tmp/ccls',
-    \   'cacheFormat': 'binary',
-    \   'diagnostics': {
-    \     'onOpen': 0,
-    \     'opChange': 1000,
-    \   },
-    \ }
-<
-  Visit https://github.com/MaskRay/ccls/wiki/Initialization-options for all
-  available options and explanations.
-
-
 ===============================================================================
   vim:tw=78:ts=2:sts=2:sw=2:ft=help:norl:
diff --git a/doc/ale-markdown.txt b/doc/ale-markdown.txt
index 4e27eb91..99848878 100644
--- a/doc/ale-markdown.txt
+++ b/doc/ale-markdown.txt
@@ -2,6 +2,17 @@
 ALE Markdown Integration                                 *ale-markdown-options*
 
 
+===============================================================================
+markdownlint                                        *ale-markdown-markdownlint*
+
+g:ale_markdown_markdownlint_options       *g:ale_markdown_markdownlint_options*
+                                          *b:ale_markdown_markdownlint_options*
+  Type: |String|
+  Default: `''`
+
+  This variable can be set to pass additional options to markdownlint.
+
+
 ===============================================================================
 mdl                                                          *ale-markdown-mdl*
 
diff --git a/doc/ale-supported-languages-and-tools.txt b/doc/ale-supported-languages-and-tools.txt
index 6d495fa9..e1a91b20 100644
--- a/doc/ale-supported-languages-and-tools.txt
+++ b/doc/ale-supported-languages-and-tools.txt
@@ -22,6 +22,7 @@ Notes:
   * `drafter`
 * AsciiDoc
   * `alex`!!
+  * `languagetool`!!
   * `proselint`
   * `redpen`
   * `textlint`
@@ -48,7 +49,7 @@ Notes:
 * C
   * `astyle`
   * `ccls`
-  * `clang`
+  * `clang` (`cc`)
   * `clangd`
   * `clang-format`
   * `clangtidy`!!
@@ -56,7 +57,7 @@ Notes:
   * `cpplint`!!
   * `cquery`
   * `flawfinder`
-  * `gcc`
+  * `gcc` (`cc`)
   * `uncrustify`
 * C#
   * `csc`!!
@@ -66,7 +67,7 @@ Notes:
 * C++ (filetype cpp)
   * `astyle`
   * `ccls`
-  * `clang`
+  * `clang` (`cc`)
   * `clangcheck`!!
   * `clangd`
   * `clang-format`
@@ -76,7 +77,7 @@ Notes:
   * `cpplint`!!
   * `cquery`
   * `flawfinder`
-  * `gcc`
+  * `gcc` (`cc`)
   * `uncrustify`
 * Chef
   * `cookstyle`
@@ -454,6 +455,7 @@ Notes:
 * Swift
   * `sourcekit-lsp`
   * `swiftformat`
+  * `swift-format`
   * `swiftlint`
 * Tcl
   * `nagelfar`!!
diff --git a/doc/ale.txt b/doc/ale.txt
index 1951d7bd..df55b544 100644
--- a/doc/ale.txt
+++ b/doc/ale.txt
@@ -684,7 +684,9 @@ g:ale_completion_enabled                             *g:ale_completion_enabled*
 
   See |ale-completion|
 
-g:ale_completion_tsserver_remove_warnings *g:ale_completion_tsserver_remove_warnings*
+
+                                    *g:ale_completion_tsserver_remove_warnings*
+g:ale_completion_tsserver_remove_warnings
 
   Type: Number
   Default: `0`
@@ -693,6 +695,7 @@ g:ale_completion_tsserver_remove_warnings *g:ale_completion_tsserver_remove_warn
   including those that are a warning. Warnings can be excluded from completed
   items by setting it to `1`.
 
+
 g:ale_completion_autoimport                       *g:ale_completion_autoimport*
 
   Type: Number
@@ -2320,16 +2323,15 @@ documented in additional help files.
     bibclean..............................|ale-bib-bibclean|
   c.......................................|ale-c-options|
     astyle................................|ale-c-astyle|
-    clang.................................|ale-c-clang|
+    cc....................................|ale-c-cc|
+    ccls..................................|ale-c-ccls|
     clangd................................|ale-c-clangd|
     clang-format..........................|ale-c-clangformat|
     clangtidy.............................|ale-c-clangtidy|
     cppcheck..............................|ale-c-cppcheck|
     cquery................................|ale-c-cquery|
     flawfinder............................|ale-c-flawfinder|
-    gcc...................................|ale-c-gcc|
     uncrustify............................|ale-c-uncrustify|
-    ccls..................................|ale-c-ccls|
   chef....................................|ale-chef-options|
     cookstyle.............................|ale-chef-cookstyle|
     foodcritic............................|ale-chef-foodcritic|
@@ -2343,9 +2345,10 @@ documented in additional help files.
     cmake-format..........................|ale-cmake-cmakeformat|
   cpp.....................................|ale-cpp-options|
     astyle................................|ale-cpp-astyle|
-    clang.................................|ale-cpp-clang|
-    clangd................................|ale-cpp-clangd|
+    cc....................................|ale-cpp-cc|
+    ccls..................................|ale-cpp-ccls|
     clangcheck............................|ale-cpp-clangcheck|
+    clangd................................|ale-cpp-clangd|
     clang-format..........................|ale-cpp-clangformat|
     clangtidy.............................|ale-cpp-clangtidy|
     clazy.................................|ale-cpp-clazy|
@@ -2353,9 +2356,7 @@ documented in additional help files.
     cpplint...............................|ale-cpp-cpplint|
     cquery................................|ale-cpp-cquery|
     flawfinder............................|ale-cpp-flawfinder|
-    gcc...................................|ale-cpp-gcc|
     uncrustify............................|ale-cpp-uncrustify|
-    ccls..................................|ale-cpp-ccls|
   c#......................................|ale-cs-options|
     csc...................................|ale-cs-csc|
     mcs...................................|ale-cs-mcs|
@@ -2503,6 +2504,7 @@ documented in additional help files.
     luac..................................|ale-lua-luac|
     luacheck..............................|ale-lua-luacheck|
   markdown................................|ale-markdown-options|
+    markdownlint..........................|ale-markdown-markdownlint|
     mdl...................................|ale-markdown-mdl|
     prettier..............................|ale-markdown-prettier|
     remark-lint...........................|ale-markdown-remark-lint|
@@ -2809,7 +2811,13 @@ ALEGoToDefinition `<options>`                               *ALEGoToDefinition*
   command. Otherwise, Vim will refuse to leave the buffer you're jumping from
   unless you have saved your edits.
 
-  A plug mapping `<Plug>(ale_go_to_definition)` is defined for this command.
+  The following Plug mappings are defined for this command, which correspond
+  to the following commands.
+
+  `<Plug>(ale_go_to_definition)`           - `:ALEGoToDefinition`
+  `<Plug>(ale_go_to_definition_in_tab)`    - `:ALEGoToDefinition -tab`
+  `<Plug>(ale_go_to_definition_in_split)`  - `:ALEGoToDefinition -split`
+  `<Plug>(ale_go_to_definition_in_vsplit)` - `:ALEGoToDefinition -vsplit`
 
 
 ALEGoToTypeDefinition                                   *ALEGoToTypeDefinition*
@@ -2831,8 +2839,13 @@ ALEGoToTypeDefinition                                   *ALEGoToTypeDefinition*
   You can jump back to the position you were at before going to the definition
   of something with jump motions like CTRL-O. See |jump-motions|.
 
-  A plug mapping `<Plug>(ale_go_to_type_definition)` is defined for this
-  command.
+  The following Plug mappings are defined for this command, which correspond
+  to the following commands.
+
+  `<Plug>(ale_go_to_type_definition)`           - `:ALEGoToTypeDefinition`
+  `<Plug>(ale_go_to_type_definition_in_tab)`    - `:ALEGoToTypeDefinition -tab`
+  `<Plug>(ale_go_to_type_definition_in_split)`  - `:ALEGoToTypeDefinition -split`
+  `<Plug>(ale_go_to_type_definition_in_vsplit)` - `:ALEGoToTypeDefinition -vsplit`
 
 
 ALEHover                                                             *ALEHover*
diff --git a/plugin/ale.vim b/plugin/ale.vim
index 65c5a77c..0651dd4b 100644
--- a/plugin/ale.vim
+++ b/plugin/ale.vim
@@ -207,19 +207,9 @@ command! -bar ALEFixSuggest :call ale#fix#registry#Suggest(&filetype)
 " Go to definition for tsserver and LSP
 command! -bar -nargs=* ALEGoToDefinition :call ale#definition#GoToCommandHandler('', <f-args>)
 
-" Deprecated commands we have to keep for now.
-command! -bar ALEGoToDefinitionInTab :call ale#definition#GoTo({'open_in': 'tab', 'deprecated_command': 'ALEGoToDefinitionInTab'})
-command! -bar ALEGoToDefinitionInSplit :call ale#definition#GoTo({'open_in': 'split', 'deprecated_command': 'ALEGoToDefinitionInSplit'})
-command! -bar ALEGoToDefinitionInVSplit :call ale#definition#GoTo({'open_in': 'vsplit', 'deprecated_command': 'ALEGoToDefinitionInVSplit'})
-
 " Go to type definition for tsserver and LSP
 command! -bar -nargs=* ALEGoToTypeDefinition :call ale#definition#GoToCommandHandler('type', <f-args>)
 
-" Deprecated commands we have to keep for now.
-command! -bar ALEGoToTypeDefinitionInTab :call ale#definition#GoToType({'open_in': 'tab', 'deprecated_command': 'ALEGoToTypeDefinitionInTab'})
-command! -bar ALEGoToTypeDefinitionInSplit :call ale#definition#GoToType({'open_in': 'split', 'deprecated_command': 'ALEGoToTypeDefinitionInSplit'})
-command! -bar ALEGoToTypeDefinitionInVSplit :call ale#definition#GoToType({'open_in': 'vsplit', 'deprecated_command': 'ALEGoToTypeDefinitionInVSplit'})
-
 " Repeat a previous selection in the preview window
 command! -bar ALERepeatSelection :call ale#preview#RepeatSelection()
 
@@ -270,7 +260,13 @@ nnoremap <silent> <Plug>(ale_lint) :ALELint<Return>
 nnoremap <silent> <Plug>(ale_detail) :ALEDetail<Return>
 nnoremap <silent> <Plug>(ale_fix) :ALEFix<Return>
 nnoremap <silent> <Plug>(ale_go_to_definition) :ALEGoToDefinition<Return>
+nnoremap <silent> <Plug>(ale_go_to_definition_in_tab) :ALEGoToDefinition -tab<Return>
+nnoremap <silent> <Plug>(ale_go_to_definition_in_split) :ALEGoToDefinition -split<Return>
+nnoremap <silent> <Plug>(ale_go_to_definition_in_vsplit) :ALEGoToDefinition -vsplit<Return>
 nnoremap <silent> <Plug>(ale_go_to_type_definition) :ALEGoToTypeDefinition<Return>
+nnoremap <silent> <Plug>(ale_go_to_type_definition_in_tab) :ALEGoToTypeDefinition -tab<Return>
+nnoremap <silent> <Plug>(ale_go_to_type_definition_in_split) :ALEGoToTypeDefinition -split<Return>
+nnoremap <silent> <Plug>(ale_go_to_type_definition_in_vsplit) :ALEGoToTypeDefinitionIn -vsplit<Return>
 nnoremap <silent> <Plug>(ale_find_references) :ALEFindReferences<Return>
 nnoremap <silent> <Plug>(ale_hover) :ALEHover<Return>
 nnoremap <silent> <Plug>(ale_documentation) :ALEDocumentation<Return>
@@ -278,14 +274,6 @@ inoremap <silent> <Plug>(ale_complete) <C-\><C-O>:ALEComplete<Return>
 nnoremap <silent> <Plug>(ale_rename) :ALERename<Return>
 nnoremap <silent> <Plug>(ale_repeat_selection) :ALERepeatSelection<Return>
 
-" Deprecated <Plug> mappings
-nnoremap <silent> <Plug>(ale_go_to_definition_in_tab) :ALEGoToDefinitionInTab<Return>
-nnoremap <silent> <Plug>(ale_go_to_definition_in_split) :ALEGoToDefinitionInSplit<Return>
-nnoremap <silent> <Plug>(ale_go_to_definition_in_vsplit) :ALEGoToDefinitionInVSplit<Return>
-nnoremap <silent> <Plug>(ale_go_to_type_definition_in_tab) :ALEGoToTypeDefinitionInTab<Return>
-nnoremap <silent> <Plug>(ale_go_to_type_definition_in_split) :ALEGoToTypeDefinitionInSplit<Return>
-nnoremap <silent> <Plug>(ale_go_to_type_definition_in_vsplit) :ALEGoToTypeDefinitionInVSplit<Return>
-
 " Set up autocmd groups now.
 call ale#events#Init()
 
diff --git a/run-tests b/run-tests
index c71f90d1..1d452a72 100755
--- a/run-tests
+++ b/run-tests
@@ -83,6 +83,13 @@ while [ $# -ne 0 ]; do
         run_neovim_03_tests=0
         shift
     ;;
+    --fast)
+        run_vim_80_tests=0
+        run_vim_81_tests=0
+        run_neovim_02_tests=0
+        run_neovim_03_tests=1
+        shift
+    ;;
     --help)
         echo 'Usage: ./run-tests [OPTION]... [FILE]...'
         echo
@@ -99,6 +106,7 @@ while [ $# -ne 0 ]; do
         echo '  --vim-80-only     Run tests only for Vim 8.0'
         echo '  --vim-81-only     Run tests only for Vim 8.1'
         echo '  --linters-only    Run only Vint and custom checks'
+        echo '  --fast            Run only the fastest Vim and custom checks'
         echo '  --help            Show this help text'
         echo '  --                Stop parsing options after this'
         exit 0
diff --git a/supported-tools.md b/supported-tools.md
index 7b884ff5..f15bd79a 100644
--- a/supported-tools.md
+++ b/supported-tools.md
@@ -31,6 +31,7 @@ formatting.
   * [drafter](https://github.com/apiaryio/drafter)
 * AsciiDoc
   * [alex](https://github.com/wooorm/alex) :floppy_disk:
+  * [languagetool](https://languagetool.org/) :floppy_disk:
   * [proselint](http://proselint.com/)
   * [redpen](http://redpen.cc/)
   * [textlint](https://textlint.github.io/)
@@ -463,6 +464,7 @@ formatting.
 * Swift
   * [sourcekit-lsp](https://github.com/apple/sourcekit-lsp)
   * [swiftformat](https://github.com/nicklockwood/SwiftFormat)
+  * [swift-format](https://github.com/apple/swift-format)
   * [swiftlint](https://github.com/realm/SwiftLint)
 * Tcl
   * [nagelfar](http://nagelfar.sourceforge.net) :floppy_disk:
diff --git a/test/command_callback/test_c_cc_command_callbacks.vader b/test/command_callback/test_c_cc_command_callbacks.vader
new file mode 100644
index 00000000..9d71d941
--- /dev/null
+++ b/test/command_callback/test_c_cc_command_callbacks.vader
@@ -0,0 +1,55 @@
+Before:
+  Save g:ale_c_parse_makefile
+  Save g:ale_history_enabled
+
+  let g:ale_c_parse_makefile = 0
+  let g:ale_history_enabled = 0
+
+  let g:get_cflags_return_value = ''
+  let g:executable_map = {}
+
+  runtime autoload/ale/c.vim
+  runtime autoload/ale/engine.vim
+
+  function! ale#engine#IsExecutable(buffer, executable) abort
+    return has_key(g:executable_map, a:executable)
+  endfunction
+
+  function! ale#c#GetCFlags(buffer, output) abort
+    return g:get_cflags_return_value
+  endfunction
+
+  call ale#assert#SetUpLinterTest('c', 'cc')
+
+  let b:command_tail = ' -S -x c'
+  \   . ' -o ' . (has('win32') ? 'nul': '/dev/null')
+  \   . ' -iquote ' . ale#Escape(getcwd())
+  \   . ' -std=c11 -Wall -'
+
+After:
+  unlet! g:get_cflags_return_value
+  unlet! g:executable_map
+  unlet! b:command_tail
+
+  runtime autoload/ale/c.vim
+  runtime autoload/ale/engine.vim
+
+  call ale#assert#TearDownLinterTest()
+
+Execute(clang should be used instead of gcc, if available):
+  let g:executable_map = {'clang': 1}
+
+  AssertLinter 'clang', [ale#Escape('clang') . b:command_tail]
+
+Execute(The executable should be configurable):
+  AssertLinter 'gcc', [ale#Escape('gcc') . b:command_tail]
+
+  let b:ale_c_cc_executable = 'foobar'
+
+  AssertLinter 'foobar', [ale#Escape('foobar') . b:command_tail]
+
+Execute(The -std flag should be replaced by parsed C flags):
+  let b:command_tail = substitute(b:command_tail, 'c11', 'c99 ', '')
+  let g:get_cflags_return_value = '-std=c99'
+
+  AssertLinter 'gcc', ale#Escape('gcc') . b:command_tail
diff --git a/test/command_callback/test_c_clang_command_callbacks.vader b/test/command_callback/test_c_clang_command_callbacks.vader
deleted file mode 100644
index b8c02e4d..00000000
--- a/test/command_callback/test_c_clang_command_callbacks.vader
+++ /dev/null
@@ -1,20 +0,0 @@
-Before:
-  Save g:ale_c_parse_makefile
-  let g:ale_c_parse_makefile = 0
-
-  call ale#assert#SetUpLinterTest('c', 'clang')
-  let b:command_tail = ' -S -x c -fsyntax-only -iquote'
-  \   . ' ' . ale#Escape(getcwd())
-  \   . ' -std=c11 -Wall -'
-
-After:
-  unlet! b:command_tail
-
-  call ale#assert#TearDownLinterTest()
-
-Execute(The executable should be configurable):
-  AssertLinter 'clang', [ale#Escape('clang') . b:command_tail]
-
-  let b:ale_c_clang_executable = 'foobar'
-
-  AssertLinter 'foobar', [ale#Escape('foobar') . b:command_tail]
diff --git a/test/command_callback/test_c_gcc_command_callbacks.vader b/test/command_callback/test_c_gcc_command_callbacks.vader
deleted file mode 100644
index 2dbb8b7c..00000000
--- a/test/command_callback/test_c_gcc_command_callbacks.vader
+++ /dev/null
@@ -1,22 +0,0 @@
-Before:
-  Save g:ale_c_parse_makefile
-  let g:ale_c_parse_makefile = 0
-
-  call ale#assert#SetUpLinterTest('c', 'gcc')
-
-  let b:command_tail = ' -S -x c'
-  \   . ' -o ' . (has('win32') ? 'nul': '/dev/null')
-  \   . ' -iquote ' . ale#Escape(getcwd())
-  \   . ' -std=c11 -Wall -'
-
-After:
-  call ale#assert#TearDownLinterTest()
-
-  unlet! b:command_tail
-
-Execute(The executable should be configurable):
-  AssertLinter 'gcc', [ale#Escape('gcc') . b:command_tail]
-
-  let b:ale_c_gcc_executable = 'foobar'
-
-  AssertLinter 'foobar', [ale#Escape('foobar') . b:command_tail]
diff --git a/test/command_callback/test_c_import_paths.vader b/test/command_callback/test_c_import_paths.vader
index e6102998..8384a659 100644
--- a/test/command_callback/test_c_import_paths.vader
+++ b/test/command_callback/test_c_import_paths.vader
@@ -7,6 +7,7 @@ Before:
   Save g:__ale_c_project_filenames
 
   let g:original_project_filenames = g:__ale_c_project_filenames
+  let g:executable_map = {}
 
   " Remove the .git/HEAD dir for C import paths for these tests.
   " The tests run inside of a git repo.
@@ -18,17 +19,26 @@ Before:
   let g:ale_c_parse_compile_commands = 0
   let g:ale_c_parse_makefile = 0
 
+  runtime autoload/ale/engine.vim
+
+  function! ale#engine#IsExecutable(buffer, executable) abort
+    return has_key(g:executable_map, a:executable)
+  endfunction
+
 After:
   Restore
 
   unlet! g:original_project_filenames
+  unlet! g:executable_map
+
+  runtime autoload/ale/engine.vim
 
   call ale#assert#TearDownLinterTest()
 
-Execute(The C GCC handler should include 'include' directories for projects with a Makefile):
-  call ale#assert#SetUpLinterTest('c', 'gcc')
+Execute(The C cc linter should include 'include' directories for projects with a Makefile):
+  call ale#assert#SetUpLinterTest('c', 'cc')
   call ale#test#SetFilename('../test_c_projects/makefile_project/subdir/file.c')
-  let g:ale_c_gcc_options = ''
+  let g:ale_c_cc_options = ''
 
   AssertLinter 'gcc',
   \ ale#Escape('gcc')
@@ -37,10 +47,10 @@ Execute(The C GCC handler should include 'include' directories for projects with
   \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/makefile_project/include'))
   \   . ' -'
 
-Execute(The C GCC handler should include 'include' directories for projects with a configure file):
-  call ale#assert#SetUpLinterTest('c', 'gcc')
+Execute(The C cc linter should include 'include' directories for projects with a configure file):
+  call ale#assert#SetUpLinterTest('c', 'cc')
   call ale#test#SetFilename('../test_c_projects/configure_project/subdir/file.c')
-  let g:ale_c_gcc_options = ''
+  let g:ale_c_cc_options = ''
 
   AssertLinter 'gcc',
   \ ale#Escape('gcc')
@@ -49,10 +59,10 @@ Execute(The C GCC handler should include 'include' directories for projects with
   \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/configure_project/include'))
   \   . ' -'
 
-Execute(The C GCC handler should include root directories for projects with .h files in them):
-  call ale#assert#SetUpLinterTest('c', 'gcc')
+Execute(The C cc linter should include root directories for projects with .h files in them):
+  call ale#assert#SetUpLinterTest('c', 'cc')
   call ale#test#SetFilename('../test_c_projects/h_file_project/subdir/file.c')
-  let g:ale_c_gcc_options = ''
+  let g:ale_c_cc_options = ''
 
   AssertLinter 'gcc',
   \ ale#Escape('gcc')
@@ -61,10 +71,10 @@ Execute(The C GCC handler should include root directories for projects with .h f
   \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/h_file_project'))
   \   . ' -'
 
-Execute(The C GCC handler should include root directories for projects with .hpp files in them):
-  call ale#assert#SetUpLinterTest('c', 'gcc')
+Execute(The C cc linter should include root directories for projects with .hpp files in them):
+  call ale#assert#SetUpLinterTest('c', 'cc')
   call ale#test#SetFilename('../test_c_projects/hpp_file_project/subdir/file.c')
-  let g:ale_c_gcc_options = ''
+  let g:ale_c_cc_options = ''
 
   AssertLinter 'gcc',
   \ ale#Escape('gcc')
@@ -73,54 +83,6 @@ Execute(The C GCC handler should include root directories for projects with .hpp
   \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/hpp_file_project'))
   \   . ' -'
 
-Execute(The C Clang handler should include 'include' directories for projects with a Makefile):
-  call ale#assert#SetUpLinterTest('c', 'clang')
-  call ale#test#SetFilename('../test_c_projects/makefile_project/subdir/file.c')
-  let g:ale_c_clang_options = ''
-
-  AssertLinter 'clang',
-  \   ale#Escape('clang')
-  \   . ' -S -x c -fsyntax-only'
-  \   . ' -iquote ' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/makefile_project/subdir'))
-  \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/makefile_project/include'))
-  \   . ' -'
-
-Execute(The C Clang handler should include 'include' directories for projects with a configure file):
-  call ale#assert#SetUpLinterTest('c', 'clang')
-  call ale#test#SetFilename('../test_c_projects/h_file_project/subdir/file.c')
-  let g:ale_c_clang_options = ''
-
-  AssertLinter 'clang',
-  \   ale#Escape('clang')
-  \   . ' -S -x c -fsyntax-only'
-  \   . ' -iquote ' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/h_file_project/subdir'))
-  \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/h_file_project'))
-  \   . ' -'
-
-Execute(The C Clang handler should include root directories for projects with .h files in them):
-  call ale#assert#SetUpLinterTest('c', 'clang')
-  call ale#test#SetFilename('../test_c_projects/h_file_project/subdir/file.c')
-  let g:ale_c_clang_options = ''
-
-  AssertLinter 'clang',
-  \   ale#Escape('clang')
-  \   . ' -S -x c -fsyntax-only'
-  \   . ' -iquote ' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/h_file_project/subdir'))
-  \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/h_file_project'))
-  \   . ' -'
-
-Execute(The C Clang handler should include root directories for projects with .hpp files in them):
-  call ale#assert#SetUpLinterTest('c', 'clang')
-  call ale#test#SetFilename('../test_c_projects/hpp_file_project/subdir/file.c')
-  let g:ale_c_clang_options = ''
-
-  AssertLinter 'clang',
-  \   ale#Escape('clang')
-  \   . ' -S -x c -fsyntax-only'
-  \   . ' -iquote ' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/hpp_file_project/subdir'))
-  \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/hpp_file_project'))
-  \   . ' -'
-
 Execute(The C ClangTidy handler should include 'include' directories for projects with a Makefile):
   call ale#assert#SetUpLinterTest('c', 'clangtidy')
   call ale#test#SetFilename('../test_c_projects/makefile_project/subdir/file.cpp')
@@ -131,10 +93,10 @@ Execute(The C ClangTidy handler should include 'include' directories for project
   \ . ' %s '
   \ . '-- -I' . ale#Escape(ale#path#Simplify(g:dir . '/../test_c_projects/makefile_project/include'))
 
-Execute(The C++ GCC handler should include 'include' directories for projects with a Makefile):
-  call ale#assert#SetUpLinterTest('cpp', 'gcc')
+Execute(The C++ cc linter should include 'include' directories for projects with a Makefile):
+  call ale#assert#SetUpLinterTest('cpp', 'cc')
   call ale#test#SetFilename('../test_c_projects/makefile_project/subdir/file.cpp')
-  let g:ale_cpp_gcc_options = ''
+  let g:ale_cpp_cc_options = ''
 
   AssertLinter 'gcc',
   \   ale#Escape('gcc')
@@ -143,10 +105,10 @@ Execute(The C++ GCC handler should include 'include' directories for projects wi
   \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/makefile_project/include'))
   \   . ' -'
 
-Execute(The C++ GCC handler should include 'include' directories for projects with a configure file):
-  call ale#assert#SetUpLinterTest('cpp', 'gcc')
+Execute(The C++ cc linter should include 'include' directories for projects with a configure file):
+  call ale#assert#SetUpLinterTest('cpp', 'cc')
   call ale#test#SetFilename('../test_c_projects/configure_project/subdir/file.cpp')
-  let g:ale_cpp_gcc_options = ''
+  let g:ale_cpp_cc_options = ''
 
   AssertLinter 'gcc',
   \   ale#Escape('gcc')
@@ -155,10 +117,10 @@ Execute(The C++ GCC handler should include 'include' directories for projects wi
   \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/configure_project/include'))
   \   . ' -'
 
-Execute(The C++ GCC handler should include root directories for projects with .h files in them):
-  call ale#assert#SetUpLinterTest('cpp', 'gcc')
+Execute(The C++ cc linter should include root directories for projects with .h files in them):
+  call ale#assert#SetUpLinterTest('cpp', 'cc')
   call ale#test#SetFilename('../test_c_projects/h_file_project/subdir/file.cpp')
-  let g:ale_cpp_gcc_options = ''
+  let g:ale_cpp_cc_options = ''
 
   AssertLinter 'gcc',
   \   ale#Escape('gcc')
@@ -167,10 +129,10 @@ Execute(The C++ GCC handler should include root directories for projects with .h
   \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/h_file_project'))
   \   . ' -'
 
-Execute(The C++ GCC handler should include root directories for projects with .hpp files in them):
-  call ale#assert#SetUpLinterTest('cpp', 'gcc')
+Execute(The C++ cc linter should include root directories for projects with .hpp files in them):
+  call ale#assert#SetUpLinterTest('cpp', 'cc')
   call ale#test#SetFilename('../test_c_projects/hpp_file_project/subdir/file.cpp')
-  let g:ale_cpp_gcc_options = ''
+  let g:ale_cpp_cc_options = ''
 
   AssertLinter 'gcc',
   \   ale#Escape('gcc')
@@ -179,54 +141,6 @@ Execute(The C++ GCC handler should include root directories for projects with .h
   \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/hpp_file_project'))
   \   . ' -'
 
-Execute(The C++ Clang handler should include 'include' directories for projects with a Makefile):
-  call ale#assert#SetUpLinterTest('cpp', 'clang')
-  call ale#test#SetFilename('../test_c_projects/makefile_project/subdir/file.cpp')
-  let g:ale_cpp_clang_options = ''
-
-  AssertLinter 'clang++',
-  \   ale#Escape('clang++')
-  \   . ' -S -x c++ -fsyntax-only'
-  \   . ' -iquote ' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/makefile_project/subdir'))
-  \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/makefile_project/include'))
-  \   . ' -'
-
-Execute(The C++ Clang handler should include 'include' directories for projects with a configure file):
-  call ale#assert#SetUpLinterTest('cpp', 'clang')
-  call ale#test#SetFilename('../test_c_projects/configure_project/subdir/file.cpp')
-  let g:ale_cpp_clang_options = ''
-
-  AssertLinter 'clang++',
-  \   ale#Escape('clang++')
-  \   . ' -S -x c++ -fsyntax-only'
-  \   . ' -iquote ' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/configure_project/subdir'))
-  \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/configure_project/include'))
-  \   . ' -'
-
-Execute(The C++ Clang handler should include root directories for projects with .h files in them):
-  call ale#assert#SetUpLinterTest('cpp', 'clang')
-  call ale#test#SetFilename('../test_c_projects/h_file_project/subdir/file.cpp')
-  let g:ale_cpp_clang_options = ''
-
-  AssertLinter 'clang++',
-  \   ale#Escape('clang++')
-  \   . ' -S -x c++ -fsyntax-only'
-  \   . ' -iquote ' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/h_file_project/subdir'))
-  \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/h_file_project'))
-  \   . ' -'
-
-Execute(The C++ Clang handler should include root directories for projects with .hpp files in them):
-  call ale#assert#SetUpLinterTest('cpp', 'clang')
-  call ale#test#SetFilename('../test_c_projects/hpp_file_project/subdir/file.cpp')
-  let g:ale_cpp_clang_options = ''
-
-  AssertLinter 'clang++',
-  \   ale#Escape('clang++')
-  \   . ' -S -x c++ -fsyntax-only'
-  \   . ' -iquote ' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/hpp_file_project/subdir'))
-  \   . ' -I' . ale#Escape(ale#path#Simplify(g:dir .  '/../test_c_projects/hpp_file_project'))
-  \   . ' -'
-
 Execute(The C++ ClangTidy handler should include json folders for projects with suitable build directory in them):
   call ale#assert#SetUpLinterTest('cpp', 'clangtidy')
   call ale#test#SetFilename('../test_c_projects/json_project/subdir/file.cpp')
diff --git a/test/command_callback/test_cpp_clang_command_callbacks.vader b/test/command_callback/test_cpp_clang_command_callbacks.vader
deleted file mode 100644
index e96fd8e7..00000000
--- a/test/command_callback/test_cpp_clang_command_callbacks.vader
+++ /dev/null
@@ -1,19 +0,0 @@
-Before:
-  Save g:ale_c_parse_makefile
-  let g:ale_c_parse_makefile = 0
-
-  call ale#assert#SetUpLinterTest('cpp', 'clang')
-  let b:command_tail = ' -S -x c++ -fsyntax-only -iquote'
-  \   . ' ' . ale#Escape(getcwd())
-  \   . ' -std=c++14 -Wall -'
-
-After:
-  unlet! b:command_tail
-  call ale#assert#TearDownLinterTest()
-
-Execute(The executable should be configurable):
-  AssertLinter 'clang++', ale#Escape('clang++') . b:command_tail
-
-  let b:ale_cpp_clang_executable = 'foobar'
-
-  AssertLinter 'foobar', ale#Escape('foobar') . b:command_tail
diff --git a/test/command_callback/test_cpp_gcc_command_callbacks.vader b/test/command_callback/test_cpp_gcc_command_callbacks.vader
index cfa4ecc0..930cc68a 100644
--- a/test/command_callback/test_cpp_gcc_command_callbacks.vader
+++ b/test/command_callback/test_cpp_gcc_command_callbacks.vader
@@ -1,20 +1,55 @@
 Before:
   Save g:ale_c_parse_makefile
-  let g:ale_c_parse_makefile = 0
+  Save g:ale_history_enabled
+
+  let g:ale_c_parse_makefile = 0
+  let g:ale_history_enabled = 0
+
+  let g:get_cflags_return_value = ''
+  let g:executable_map = {}
+
+  runtime autoload/ale/c.vim
+  runtime autoload/ale/engine.vim
+
+  function! ale#engine#IsExecutable(buffer, executable) abort
+    return has_key(g:executable_map, a:executable)
+  endfunction
+
+  function! ale#c#GetCFlags(buffer, output) abort
+    return g:get_cflags_return_value
+  endfunction
+
+  call ale#assert#SetUpLinterTest('cpp', 'cc')
 
-  call ale#assert#SetUpLinterTest('cpp', 'gcc')
   let b:command_tail = ' -S -x c++'
   \   . ' -o ' . (has('win32') ? 'nul': '/dev/null')
   \   . ' -iquote ' . ale#Escape(getcwd())
   \   . ' -std=c++14 -Wall -'
 
 After:
+  unlet! g:get_cflags_return_value
+  unlet! g:executable_map
   unlet! b:command_tail
+
+  runtime autoload/ale/c.vim
+  runtime autoload/ale/engine.vim
+
   call ale#assert#TearDownLinterTest()
 
+Execute(clang++ should be used instead of gcc, if available):
+  let g:executable_map = {'clang++': 1}
+
+  AssertLinter 'clang++', [ale#Escape('clang++') . b:command_tail]
+
 Execute(The executable should be configurable):
+  AssertLinter 'gcc', [ale#Escape('gcc') . b:command_tail]
+
+  let b:ale_cpp_cc_executable = 'foobar'
+
+  AssertLinter 'foobar', [ale#Escape('foobar') . b:command_tail]
+
+Execute(The -std flag should be replaced by parsed C flags):
+  let b:command_tail = substitute(b:command_tail, 'c++14', 'c++11 ', '')
+  let g:get_cflags_return_value = '-std=c++11'
+
   AssertLinter 'gcc', ale#Escape('gcc') . b:command_tail
-
-  let b:ale_cpp_gcc_executable = 'foobar'
-
-  AssertLinter 'foobar', ale#Escape('foobar') . b:command_tail
diff --git a/test/command_callback/test_elixir_credo.vader b/test/command_callback/test_elixir_credo.vader
index 1a146db8..3eb88846 100644
--- a/test/command_callback/test_elixir_credo.vader
+++ b/test/command_callback/test_elixir_credo.vader
@@ -8,6 +8,18 @@ After:
 
   call ale#assert#TearDownLinterTest()
 
+Execute(Builds credo command with normal project):
+  AssertLinter 'mix',
+  \ ale#path#CdString(ale#path#Simplify(g:dir . '/elixir_paths/mix_project'))
+  \ . 'mix help credo && mix credo suggest --format=flycheck --read-from-stdin %s'
+
+Execute(Builds credo command with umbrella project):
+  call ale#test#SetFilename('elixir_paths/umbrella_project/apps/mix_project/lib/app.ex')
+
+  AssertLinter 'mix',
+  \ ale#path#CdString(ale#path#Simplify(g:dir . '/elixir_paths/umbrella_project'))
+  \ . 'mix help credo && mix credo suggest --format=flycheck --read-from-stdin %s'
+
 Execute(Builds credo command with --strict mode when set to 1):
   let g:ale_elixir_credo_strict = 1
 
diff --git a/test/command_callback/test_markdown_markdownlint_command_callback.vader b/test/command_callback/test_markdown_markdownlint_command_callback.vader
new file mode 100644
index 00000000..12766cfd
--- /dev/null
+++ b/test/command_callback/test_markdown_markdownlint_command_callback.vader
@@ -0,0 +1,13 @@
+Before:
+  call ale#assert#SetUpLinterTest('markdown', 'markdownlint')
+
+After:
+  call ale#assert#TearDownLinterTest()
+
+Execute(The default command should be correct):
+  AssertLinter 'markdownlint', ale#Escape('markdownlint') . ' %s'
+
+Execute(The options should be configurable):
+  let g:ale_markdown_markdownlint_options = '--config ~/custom/.markdownlintrc'
+
+  AssertLinter 'markdownlint', ale#Escape('markdownlint') . ' --config ~/custom/.markdownlintrc %s'
diff --git a/test/command_callback/test_swift_swiftformat_command_callbacks.vader b/test/command_callback/test_swift_swiftformat_command_callbacks.vader
new file mode 100644
index 00000000..7be20bf7
--- /dev/null
+++ b/test/command_callback/test_swift_swiftformat_command_callbacks.vader
@@ -0,0 +1,25 @@
+Before:
+  call ale#assert#SetUpLinterTest('swift', 'swiftformat')
+
+After:
+  call ale#assert#TearDownLinterTest()
+
+Execute(Should use default command when not in a swift package):
+  call ale#test#SetFilename('../swift-test-files/non-swift-package-project/src/folder/dummy.swift')
+
+  AssertLinter 'swift-format',
+  \ ale#Escape('swift-format') . ' --mode lint %t'
+
+Execute(Should use swift run when in a swift package):
+  call ale#test#SetFilename('../swift-test-files/swift-package-project/src/folder/dummy.swift')
+
+  AssertLinter 'swift',
+  \ ale#Escape('swift') . ' run swift-format --mode lint %t'
+
+Execute(Should let users configure a global executable and override local paths):
+  call ale#test#SetFilename('../swift-test-files/swift-package-project/src/folder/dummy.swift')
+
+  let g:ale_swift_swiftformat_executable = '/path/to/custom/swift-format'
+
+  AssertLinter '/path/to/custom/swift-format',
+  \ ale#Escape('/path/to/custom/swift-format') . ' --mode lint %t'
diff --git a/test/fix/test_ale_fix.vader b/test/fix/test_ale_fix.vader
index c3dd20e4..53079d16 100644
--- a/test/fix/test_ale_fix.vader
+++ b/test/fix/test_ale_fix.vader
@@ -5,12 +5,14 @@ Before:
   Save g:ale_fix_on_save
   Save g:ale_lint_on_save
   Save g:ale_echo_cursor
+  Save g:ale_command_wrapper
 
   silent! cd /testplugin/test/fix
 
   unlet! b:ale_lint_on_save
   let g:ale_enabled = 0
   let g:ale_echo_cursor = 0
+  let g:ale_command_wrapper = ''
   let g:ale_run_synchronously = 1
   let g:ale_set_lists_synchronously = 1
   let g:ale_fix_buffer_data = {}
@@ -82,56 +84,6 @@ Before:
     return [{'lnum': 1, 'col': 1, 'text': 'xxx'}]
   endfunction
 
-  function! FirstChainCallback(buffer)
-    return {'command': 'echo echoline', 'chain_with': 'SecondChainCallback'}
-  endfunction
-
-  function! FirstChainCallbackSkipped(buffer)
-    let l:ChainWith = 'SecondChainCallback'
-
-    " Test with lambdas where support is available.
-    if has('lambda')
-      let l:ChainWith = {buffer, output -> SecondChainCallback(buffer, output)}
-    endif
-
-    return {'command': '', 'chain_with': l:ChainWith}
-  endfunction
-
-  function! FirstChainCallbackSecondSkipped(buffer)
-    return {'command': 'echo skipit', 'chain_with': 'SecondChainCallback'}
-  endfunction
-
-  function! SecondChainCallback(buffer, output)
-    let l:previous_line = empty(a:output)
-    \ ? 'emptydefault'
-    \ : join(split(a:output[0]))
-
-    if l:previous_line is# 'skipit'
-      return {'command': '', 'chain_with': 'ThirdChainCallback'}
-    endif
-
-    return {
-    \ 'command': 'echo ' . l:previous_line,
-    \ 'chain_with': 'ThirdChainCallback',
-    \}
-  endfunction
-
-  function! ThirdChainCallback(buffer, output, input)
-    let l:previous_line = empty(a:output)
-    \ ? 'thirddefault'
-    \ : join(split(a:output[0]))
-
-    return a:input + [l:previous_line]
-  endfunction
-
-  function! ChainWhereLastIsSkipped(buffer)
-    return {'command': 'echo echoline', 'chain_with': 'ChainEndSkipped'}
-  endfunction
-
-  function! ChainEndSkipped(buffer, output)
-    return {'command': ''}
-  endfunction
-
   " echo will output a single blank line, and we should ingore it.
   function! IgnoredEmptyOutput(buffer, output)
     return {'command': has('win32') ? 'echo(' : 'echo'}
@@ -206,13 +158,6 @@ After:
   delfunction RemoveLastLine
   delfunction RemoveLastLineOneArg
   delfunction TestCallback
-  delfunction FirstChainCallback
-  delfunction FirstChainCallbackSkipped
-  delfunction FirstChainCallbackSecondSkipped
-  delfunction SecondChainCallback
-  delfunction ThirdChainCallback
-  delfunction ChainWhereLastIsSkipped
-  delfunction ChainEndSkipped
   delfunction SetUpLinters
   delfunction GetLastMessage
   delfunction IgnoredEmptyOutput
@@ -814,57 +759,6 @@ Execute(ALE should tolerate valid fixers with minuses in the name):
   ALEFix
   call ale#test#FlushJobs()
 
-Execute(Test fixing with chained callbacks):
-  let g:ale_fixers.testft = ['FirstChainCallback']
-  ALEFix
-  call ale#test#FlushJobs()
-
-  " The buffer shouldn't be piped in for earlier commands in the chain.
-  AssertEqual
-  \ [
-  \   string(ale#job#PrepareCommand(bufnr(''), 'echo echoline')),
-  \   string(ale#job#PrepareCommand(bufnr(''), 'echo echoline')),
-  \ ],
-  \ map(ale#history#Get(bufnr(''))[-2:-1], 'string(v:val.command)')
-
-Expect(The echoed line should be added):
-  a
-  b
-  c
-  echoline
-
-Execute(Test fixing with chained callback where the first command is skipped):
-  let g:ale_fixers.testft = ['FirstChainCallbackSkipped']
-  ALEFix
-  call ale#test#FlushJobs()
-
-Expect(The default line should be added):
-  a
-  b
-  c
-  emptydefault
-
-Execute(Test fixing with chained callback where the second command is skipped):
-  let g:ale_fixers.testft = ['FirstChainCallbackSecondSkipped']
-  ALEFix
-  call ale#test#FlushJobs()
-
-Expect(The default line should be added):
-  a
-  b
-  c
-  thirddefault
-
-Execute(Test fixing with chained callback where the final callback is skipped):
-  let g:ale_fixers.testft = ['ChainWhereLastIsSkipped']
-  ALEFix
-  call ale#test#FlushJobs()
-
-Expect(The lines should be the same):
-  a
-  b
-  c
-
 Execute(Empty output should be ignored):
   let g:ale_fixers.testft = ['IgnoredEmptyOutput']
   ALEFix
diff --git a/test/fixers/test_clangtidy_fixer_callback.vader b/test/fixers/test_clangtidy_fixer_callback.vader
index 68416b36..ca08e6bc 100644
--- a/test/fixers/test_clangtidy_fixer_callback.vader
+++ b/test/fixers/test_clangtidy_fixer_callback.vader
@@ -1,8 +1,19 @@
 Before:
+  Save g:ale_c_build_dir
   Save g:ale_c_clangtidy_executable
+  Save g:ale_c_clangtidy_checks
+  Save g:ale_c_clangtidy_extra_options
+  Save g:ale_cpp_clangtidy_executable
+  Save g:ale_cpp_clangtidy_checks
+  Save g:ale_cpp_clangtidy_extra_options
 
   " Use an invalid global executable, so we don't match it.
   let g:ale_c_clangtidy_executable = 'xxxinvalid'
+  let g:ale_c_clangtidy_checks = []
+  let g:ale_c_clangtidy_extra_options = ''
+  let g:ale_cpp_clangtidy_executable = 'xxxinvalidpp'
+  let g:ale_cpp_clangtidy_checks = []
+  let g:ale_cpp_clangtidy_extra_options = ''
   let g:ale_c_build_dir = ''
 
   call ale#test#SetDirectory('/testplugin/test/fixers')
@@ -36,16 +47,3 @@ Execute(The clangtidy callback should include any additional options):
   \     . ' -fix -fix-errors --some-option %t',
   \ },
   \ ale#fixers#clangtidy#Fix(bufnr(''))
-
-Execute(The clangtidy callback should support cpp files):
-  call ale#test#SetFilename('c_paths/dummy.cpp')
-  let g:ale_cpp_clangtidy_executable = 'invalidpp'
-  set filetype=cpp " The test fails without this
-
-  AssertEqual
-  \ {
-  \   'read_temporary_file': 1,
-  \   'command': ale#Escape(g:ale_cpp_clangtidy_executable)
-  \     . ' -fix -fix-errors %t',
-  \ },
-  \ ale#fixers#clangtidy#Fix(bufnr(''))
diff --git a/test/fixers/test_eslint_fixer_callback.vader b/test/fixers/test_eslint_fixer_callback.vader
index 400267ac..50fc6672 100644
--- a/test/fixers/test_eslint_fixer_callback.vader
+++ b/test/fixers/test_eslint_fixer_callback.vader
@@ -1,7 +1,11 @@
 Before:
   call ale#assert#SetUpFixerTest('javascript', 'eslint')
+  Save g:ale_command_wrapper
+
   runtime autoload/ale/handlers/eslint.vim
 
+  let g:ale_command_wrapper = ''
+
 After:
   call ale#assert#TearDownFixerTest()
 
diff --git a/test/fixers/test_prettier_eslint_fixer.callback.vader b/test/fixers/test_prettier_eslint_fixer.callback.vader
index 90e11672..f7bb3c61 100644
--- a/test/fixers/test_prettier_eslint_fixer.callback.vader
+++ b/test/fixers/test_prettier_eslint_fixer.callback.vader
@@ -1,5 +1,8 @@
 Before:
   call ale#assert#SetUpFixerTest('javascript', 'prettier_eslint')
+  Save g:ale_command_wrapper
+
+  let g:ale_command_wrapper = ''
 
 After:
   call ale#assert#TearDownFixerTest()
diff --git a/test/fixers/test_prettier_fixer_callback.vader b/test/fixers/test_prettier_fixer_callback.vader
index 062ae8cf..1087a160 100644
--- a/test/fixers/test_prettier_fixer_callback.vader
+++ b/test/fixers/test_prettier_fixer_callback.vader
@@ -1,5 +1,8 @@
 Before:
   call ale#assert#SetUpFixerTest('javascript', 'prettier')
+  Save g:ale_command_wrapper
+
+  let g:ale_command_wrapper = ''
 
   silent cd ..
   silent cd command_callback
diff --git a/test/fixers/test_remark_lint_fixer_callback.vader b/test/fixers/test_remark_lint_fixer_callback.vader
new file mode 100644
index 00000000..5e2e342d
--- /dev/null
+++ b/test/fixers/test_remark_lint_fixer_callback.vader
@@ -0,0 +1,24 @@
+Before:
+  Save g:ale_markdown_remark_lint_executable
+  Save g:ale_markdown_remark_lint_options
+
+After:
+  Restore
+
+Execute(The remark callback should return the correct default values):
+  AssertEqual
+  \ {
+  \   'command': ale#Escape('remark')
+  \ },
+  \ ale#fixers#remark_lint#Fix(bufnr(''))
+
+Execute(The remark executable and options should be configurable):
+  let g:ale_markdown_remark_lint_executable = '/path/to/remark'
+  let g:ale_markdown_remark_lint_options = '-h'
+
+  AssertEqual
+  \ {
+  \   'command': ale#Escape('/path/to/remark')
+  \     . ' -h',
+  \ },
+  \ ale#fixers#remark_lint#Fix(bufnr(''))
diff --git a/test/fixers/test_standard_fixer_callback.vader b/test/fixers/test_standard_fixer_callback.vader
index db9f20f6..f5e9c487 100644
--- a/test/fixers/test_standard_fixer_callback.vader
+++ b/test/fixers/test_standard_fixer_callback.vader
@@ -15,7 +15,7 @@ Execute(The executable path should be correct):
   \   'read_temporary_file': 1,
   \   'command': (has('win32') ? 'node.exe ' : '')
   \     . ale#Escape(ale#path#Simplify(g:dir . '/../eslint-test-files/react-app/node_modules/standard/bin/cmd.js'))
-  \     . ' --fix %t',
+  \     . ' --fix --stdin < %s > %t',
   \ },
   \ ale#fixers#standard#Fix(bufnr(''))
 
@@ -26,6 +26,6 @@ Execute(Custom options should be supported):
   AssertEqual
   \ {
   \   'read_temporary_file': 1,
-  \   'command': ale#Escape('standard') . ' --foo-bar --fix %t',
+  \   'command': ale#Escape('standard') . ' --foo-bar --fix --stdin < %s > %t',
   \ },
   \ ale#fixers#standard#Fix(bufnr(''))
diff --git a/test/handler/test_glslang_handler.vader b/test/handler/test_glslang_handler.vader
index d51c9852..6d3a7999 100644
--- a/test/handler/test_glslang_handler.vader
+++ b/test/handler/test_glslang_handler.vader
@@ -1,3 +1,6 @@
+Before:
+  runtime ale_linters/glsl/glslang.vim
+
 Execute(The glsl glslang handler should parse lines correctly):
   AssertEqual
   \ [
diff --git a/test/handler/test_standard_handler.vader b/test/handler/test_standard_handler.vader
index 59ebe531..31e3a36b 100644
--- a/test/handler/test_standard_handler.vader
+++ b/test/handler/test_standard_handler.vader
@@ -1,3 +1,11 @@
+Before:
+  Save g:ale_javascript_eslint_suppress_eslintignore
+
+  let g:ale_javascript_eslint_suppress_eslintignore = 0
+
+After:
+  Restore
+
 Execute(The standard handler should parse lines correctly):
   AssertEqual
   \ [
diff --git a/test/handler/test_swiftformat_handler.vader b/test/handler/test_swiftformat_handler.vader
new file mode 100644
index 00000000..3dcc4f1a
--- /dev/null
+++ b/test/handler/test_swiftformat_handler.vader
@@ -0,0 +1,28 @@
+Before:
+  runtime ale_linters/swift/swiftformat.vim
+
+After:
+  call ale#linter#Reset()
+
+Execute(The swiftformat handler should parse lines correctly):
+  AssertEqual
+  \ [
+  \   {
+  \     'lnum': 4,
+  \     'col': 21,
+  \     'type': 'W',
+  \     'code': 'DoNotUseSemicolons',
+  \     'text': 'remove '';'' and move the next statement to the new line',
+  \   },
+  \   {
+  \     'lnum': 3,
+  \     'col': 12,
+  \     'type': 'W',
+  \     'code': 'Spacing',
+  \     'text': 'remove 1 space'
+  \   },
+  \ ],
+  \ ale_linters#swift#swiftformat#Handle(bufnr(''), [
+  \   'Sources/main.swift:4:21: warning: [DoNotUseSemicolons]: remove '';'' and move the next statement to the new line',
+  \   'Sources/main.swift:3:12: warning: [Spacing]: remove 1 space',
+  \ ])
diff --git a/test/lsp/test_did_save_event.vader b/test/lsp/test_did_save_event.vader
index bdea6d98..1d811363 100644
--- a/test/lsp/test_did_save_event.vader
+++ b/test/lsp/test_did_save_event.vader
@@ -33,8 +33,8 @@ Before:
   \ 'lsp': 'stdio',
   \ 'command': 'cat - > /dev/null',
   \ 'executable': has('win32') ? 'cmd' : 'echo',
-  \ 'language_callback': 'LanguageCallback',
-  \ 'project_root_callback': 'ProjectRootCallback',
+  \ 'language': function('LanguageCallback'),
+  \ 'project_root': function('ProjectRootCallback'),
   \ })
   let g:ale_linters = {'foobar': ['dummy_linter']}
 
diff --git a/test/lsp/test_lsp_command_formatting.vader b/test/lsp/test_lsp_command_formatting.vader
index ec3b4120..e99e1dad 100644
--- a/test/lsp/test_lsp_command_formatting.vader
+++ b/test/lsp/test_lsp_command_formatting.vader
@@ -1,6 +1,10 @@
 Before:
+  Save g:ale_command_wrapper
+
   runtime autoload/ale/lsp.vim
 
+  let g:ale_command_wrapper = ''
+
   let g:args = []
 
   " Mock the StartProgram function so we can just capture the arguments.
@@ -9,6 +13,8 @@ Before:
   endfunction
 
 After:
+  Restore
+
   unlet! g:args
 
   runtime autoload/ale/lsp.vim
@@ -18,8 +24,8 @@ Execute(Command formatting should be applied correctly for LSP linters):
   \ bufnr(''),
   \ {
   \   'name': 'linter',
-  \   'language_callback': {-> 'x'},
-  \   'project_root_callback': {-> '/foo/bar'},
+  \   'language': {-> 'x'},
+  \   'project_root': {-> '/foo/bar'},
   \   'lsp': 'stdio',
   \   'executable': has('win32') ? 'cmd': 'true',
   \   'command': '%e --foo',
diff --git a/test/lsp/test_lsp_custom_request.vader b/test/lsp/test_lsp_custom_request.vader
index 04f044af..c8767e59 100644
--- a/test/lsp/test_lsp_custom_request.vader
+++ b/test/lsp/test_lsp_custom_request.vader
@@ -25,7 +25,6 @@ Before:
   \   'name': g:linter_name,
   \   'project_root': {b -> g:project_root},
   \   'aliases': [],
-  \   'language_callback': {b -> 'cpp'},
   \   'read_buffer': 1,
   \   'command': '%e'
   \ }]
diff --git a/test/lsp/test_lsp_startup.vader b/test/lsp/test_lsp_startup.vader
index c29690bf..cd9b59dd 100644
--- a/test/lsp/test_lsp_startup.vader
+++ b/test/lsp/test_lsp_startup.vader
@@ -422,3 +422,13 @@ Execute(Deferred addresses should be handled correctly):
   Assert Start()
   call ale#test#FlushJobs()
   call AssertInitSuccess('foo', 'localhost:1234', 'foobar', '/foo/bar', '')
+
+Execute(Servers that have crashed should be restarted):
+  call ale#lsp#Register('foo', '/foo/bar', {})
+  call extend(ale#lsp#GetConnections()['foo:/foo/bar'], {'initialized': 1})
+
+  " Starting the program again should reset initialized to `0`.
+  call ale#lsp#StartProgram('foo:/foo/bar', 'foobar', 'foobar --start')
+
+  AssertEqual 0, ale#lsp#GetConnections()['foo:/foo/bar']['initialized']
+  AssertEqual ['initialize'], map(PopMessages(), 'v:val[''method'']')
diff --git a/test/sign/test_linting_sets_signs.vader b/test/sign/test_linting_sets_signs.vader
index 1d1f9802..1624449a 100644
--- a/test/sign/test_linting_sets_signs.vader
+++ b/test/sign/test_linting_sets_signs.vader
@@ -10,7 +10,9 @@ Before:
   Save g:ale_set_loclist
   Save g:ale_set_quickfix
   Save g:ale_set_signs
+  Save g:ale_command_wrapper
 
+  let g:ale_command_wrapper = ''
   let g:ale_buffer_info = {}
   let g:ale_run_synchronously = 1
   unlet! g:ale_run_synchronously_callbacks
diff --git a/test/sign/test_sign_placement.vader b/test/sign/test_sign_placement.vader
index d8d05b28..7b80d83c 100644
--- a/test/sign/test_sign_placement.vader
+++ b/test/sign/test_sign_placement.vader
@@ -6,7 +6,9 @@ Before:
   Save g:ale_set_loclist
   Save g:ale_set_quickfix
   Save g:ale_set_signs
+  Save g:ale_command_wrapper
 
+  let g:ale_command_wrapper = ''
   let g:ale_buffer_info = {}
   let g:ale_run_synchronously = 1
   let g:ale_set_signs = 1
diff --git a/test/test_c_flag_parsing.vader b/test/test_c_flag_parsing.vader
index 8ae6f9dc..e9830db8 100644
--- a/test/test_c_flag_parsing.vader
+++ b/test/test_c_flag_parsing.vader
@@ -340,6 +340,7 @@ Execute(CFlags we want to pass):
   \ . ' -iquote ' . ale#Escape(ale#path#Simplify(g:dir. '/test_c_projects/makefile_project/incquote'))
   \ . ' -isystem ' . ale#Escape(ale#path#Simplify(g:dir. '/test_c_projects/makefile_project/incsystem'))
   \ . ' -idirafter ' . ale#Escape(ale#path#Simplify(g:dir. '/test_c_projects/makefile_project/incafter'))
+  \ . ' -iframework ' . ale#Escape(ale#path#Simplify(g:dir. '/test_c_projects/makefile_project/incframework'))
   \ . ' -Dmacro=value -D macro2 -Bbdir -B bdir2'
   \ . ' -iprefix prefix -iwithprefix prefix2 -iwithprefixbefore prefix3'
   \ . ' -isysroot sysroot --sysroot=test --no-sysroot-suffix -imultilib multidir'
@@ -349,7 +350,7 @@ Execute(CFlags we want to pass):
   \ ale#c#ParseCFlags(
   \   ale#path#Simplify(g:dir. '/test_c_projects/makefile_project'),
   \   'gcc'
-  \ . ' -Iinc -I include -iquote incquote -isystem incsystem -idirafter incafter'
+  \ . ' -Iinc -I include -iquote incquote -isystem incsystem -idirafter incafter -iframework incframework'
   \ . ' -Dmacro=value -D macro2 -Bbdir -B bdir2'
   \ . ' -iprefix prefix -iwithprefix prefix2 -iwithprefixbefore prefix3'
   \ . ' -isysroot sysroot --sysroot=test --no-sysroot-suffix -imultilib multidir'
@@ -364,5 +365,16 @@ Execute(CFlags we dont want to pass):
   \ ale#c#ParseCFlags(
   \   ale#path#Simplify(g:dir. '/test_c_projects/makefile_project'),
   \   'gcc -Wl,option -Wa,option -Wp,option filename.c somelib.a '
-  \ . '-fdump-file=name -fdiagnostics-arg -fno-show-column'
+  \ . '-fdump-file=name -fdiagnostics-arg -fno-show-column -fstack-usage'
+  \ )
+
+Execute(Expanding @file in CFlags):
+  AssertEqual
+  \ '-DARGS1 -DARGS2 -O2',
+  \ ale#c#ParseCFlags(
+  \   ale#path#Simplify(g:dir. '/test_c_projects/makefile_project'),
+  \   'gcc'
+  \   . ' -g'
+  \   . ' @./args'
+  \   . ' -O2',
   \ )
diff --git a/test/test_c_projects/makefile_project/args b/test/test_c_projects/makefile_project/args
new file mode 100644
index 00000000..ccaf82ad
--- /dev/null
+++ b/test/test_c_projects/makefile_project/args
@@ -0,0 +1,3 @@
+foolib.a
+-DARGS1
+@subdir/args
diff --git a/test/test_c_projects/makefile_project/subdir/args b/test/test_c_projects/makefile_project/subdir/args
new file mode 100644
index 00000000..3fe9c3fe
--- /dev/null
+++ b/test/test_c_projects/makefile_project/subdir/args
@@ -0,0 +1 @@
+-DARGS2
diff --git a/test/test_command_chain.vader b/test/test_command_chain.vader
deleted file mode 100644
index 329ebc97..00000000
--- a/test/test_command_chain.vader
+++ /dev/null
@@ -1,73 +0,0 @@
-Before:
-  Save &shell, g:ale_run_synchronously
-  let g:ale_run_synchronously = 1
-  unlet! g:ale_run_synchronously_callbacks
-
-  if !has('win32')
-    set shell=/bin/sh
-  endif
-
-  let g:linter_output = []
-  let g:first_echo_called = 0
-  let g:second_echo_called = 0
-  let g:final_callback_called = 0
-
-  function! CollectResults(buffer, output)
-    let g:final_callback_called = 1
-    let g:linter_output = map(copy(a:output), 'join(split(v:val))')
-    return []
-  endfunction
-  function! RunFirstEcho(buffer)
-    let g:first_echo_called = 1
-
-    return 'echo foo'
-  endfunction
-  function! RunSecondEcho(buffer, output)
-    let g:second_echo_called = 1
-
-    return 'echo bar'
-  endfunction
-
-  call ale#linter#Define('foobar', {
-  \ 'name': 'testlinter',
-  \ 'callback': 'CollectResults',
-  \ 'executable': has('win32') ? 'cmd' : 'echo',
-  \ 'command_chain': [
-  \   {
-  \     'callback': 'RunFirstEcho',
-  \     'output_stream': 'stdout',
-  \     'read_buffer': 0,
-  \   },
-  \   {
-  \     'callback': 'RunSecondEcho',
-  \     'output_stream': 'stdout',
-  \     'read_buffer': 0,
-  \   },
-  \ ],
-  \})
-
-After:
-  Restore
-  unlet! g:ale_run_synchronously_callbacks
-  unlet! g:first_echo_called
-  unlet! g:second_echo_called
-  unlet! g:final_callback_called
-  unlet! g:linter_output
-  let g:ale_buffer_info = {}
-  call ale#linter#Reset()
-  delfunction CollectResults
-  delfunction RunFirstEcho
-  delfunction RunSecondEcho
-
-Given foobar (Some imaginary filetype):
-  anything
-
-Execute(Check the results of running the chain):
-  AssertEqual 'foobar', &filetype
-  call ale#Queue(0)
-  call ale#test#FlushJobs()
-
-  Assert g:first_echo_called, 'The first chain item was not called'
-  Assert g:second_echo_called, 'The second chain item was not called'
-  Assert g:final_callback_called, 'The final callback was not called'
-  AssertEqual ['bar'], g:linter_output
diff --git a/test/test_engine_invocation.vader b/test/test_engine_invocation.vader
deleted file mode 100644
index af713953..00000000
--- a/test/test_engine_invocation.vader
+++ /dev/null
@@ -1,108 +0,0 @@
-Before:
-  function! CollectResults(buffer, output)
-    return []
-  endfunction
-
-  function! FirstChainFunction(buffer)
-    return 'first'
-  endfunction
-
-  function! SecondChainFunction(buffer, output)
-    " We'll skip this command
-    return ''
-  endfunction
-
-  function! ThirdChainFunction(buffer, output)
-    return 'third'
-  endfunction
-
-  function! FourthChainFunction(buffer, output)
-    return 'fourth'
-  endfunction
-
-  let g:linter = {
-  \ 'name': 'testlinter',
-  \ 'callback': 'CollectResults',
-  \ 'executable': 'echo',
-  \ 'command_chain': [
-  \   {'callback': 'FirstChainFunction'},
-  \   {'callback': 'SecondChainFunction'},
-  \   {'callback': 'ThirdChainFunction'},
-  \   {'callback': 'FourthChainFunction'},
-  \ ],
-  \ 'read_buffer': 1,
-  \}
-
-  function! ProcessIndex(chain_index)
-    let [l:command, l:options] = ale#engine#ProcessChain(347, '', g:linter, a:chain_index, [])
-    let l:options.command = l:command
-
-    return l:options
-  endfunction
-
-After:
-  delfunction CollectResults
-  delfunction FirstChainFunction
-  delfunction SecondChainFunction
-  delfunction ThirdChainFunction
-  delfunction ProcessIndex
-  unlet! g:linter
-  unlet! g:result
-
-Execute(Engine invocation should return the command for the first item correctly):
-  let g:result = ProcessIndex(0)
-
-  AssertEqual 'first', g:result.command
-  AssertEqual 1, g:result.next_chain_index
-
-Execute(Engine invocation should return the command for the second item correctly):
-  let g:result = ProcessIndex(1)
-
-  AssertEqual 'third', g:result.command
-  AssertEqual 3, g:result.next_chain_index
-
-Execute(Engine invocation should return the command for the fourth item correctly):
-  let g:result = ProcessIndex(3)
-
-  AssertEqual 'fourth', g:result.command
-  AssertEqual 4, g:result.next_chain_index
-
-Execute(Engine invocation should allow read_buffer to be enabled for a command in the middle of a chain):
-  let g:linter.command_chain[2].read_buffer = 1
-
-  let g:result = ProcessIndex(2)
-
-  AssertEqual g:result.command, 'third'
-  AssertEqual g:result.read_buffer, 1
-
-Execute(Engine invocation should allow read_buffer to be disabled for the end of a chain):
-  let g:linter.command_chain[3].read_buffer = 0
-
-  let g:result = ProcessIndex(3)
-
-  AssertEqual g:result.command, 'fourth'
-  AssertEqual g:result.read_buffer, 0
-
-Execute(Engine invocation should not use read_buffer from earlier items in a chain):
-  let g:linter.command_chain[1].read_buffer = 1
-
-  let g:result = ProcessIndex(1)
-
-  AssertEqual g:result.command, 'third'
-  AssertEqual g:result.read_buffer, 0
-
-Execute(Engine invocation should allow the output_stream setting to be changed in the middle of a chain):
-  let g:linter.command_chain[2].output_stream = 'both'
-
-  let g:result = ProcessIndex(2)
-
-  AssertEqual g:result.command, 'third'
-  AssertEqual g:result.output_stream, 'both'
-
-Execute(Engine invocation should not use output_stream from earlier items in a chain):
-  let g:linter.command_chain[1].output_stream = 'both'
-
-  let g:result = ProcessIndex(1)
-
-  AssertEqual g:result.command, 'third'
-  AssertEqual g:result.output_stream, 'stdout'
diff --git a/test/test_go_to_definition.vader b/test/test_go_to_definition.vader
index a517bd54..f2f34280 100644
--- a/test/test_go_to_definition.vader
+++ b/test/test_go_to_definition.vader
@@ -514,7 +514,7 @@ Execute(LSP tab type definition requests should be sent):
   let b:ale_linters = ['pyls']
   call setpos('.', [bufnr(''), 1, 5, 0])
 
-  ALEGoToTypeDefinitionInTab
+  ALEGoToTypeDefinition -tab
 
   " We shouldn't register the callback yet.
   AssertEqual '''''', string(g:Callback)
diff --git a/test/test_linter_defintion_processing.vader b/test/test_linter_defintion_processing.vader
index cd32ebc8..2c85299b 100644
--- a/test/test_linter_defintion_processing.vader
+++ b/test/test_linter_defintion_processing.vader
@@ -39,13 +39,13 @@ Execute (PreProcess should throw when then callback is not a function):
   \})
   AssertEqual '`callback` must be defined with a callback to accept output', g:vader_exception
 
-Execute (PreProcess should throw when there is no executable or executable_callback):
+Execute (PreProcess should throw when there is no executable):
   AssertThrows call ale#linter#PreProcess('testft', {
   \ 'name': 'foo',
   \ 'callback': 'SomeFunction',
   \ 'command': 'echo',
   \})
-  AssertEqual 'Either `executable` or `executable_callback` must be defined', g:vader_exception
+  AssertEqual '`executable` must be defined', g:vader_exception
 
 Execute (PreProcess should throw when executable is not a string):
   AssertThrows call ale#linter#PreProcess('testft', {
@@ -56,15 +56,6 @@ Execute (PreProcess should throw when executable is not a string):
   \})
   AssertEqual '`executable` must be a String or Function if defined', g:vader_exception
 
-Execute (PreProcess should throw when executable_callback is not a callback):
-  AssertThrows call ale#linter#PreProcess('testft', {
-  \ 'name': 'foo',
-  \ 'callback': 'SomeFunction',
-  \ 'executable_callback': 123,
-  \ 'command': 'echo',
-  \})
-  AssertEqual '`executable_callback` must be a callback if defined', g:vader_exception
-
 Execute (PreProcess should allow executable to be a callback):
   call ale#linter#PreProcess('testft', {
   \ 'name': 'foo',
@@ -79,7 +70,7 @@ Execute (PreProcess should throw when there is no command):
   \ 'callback': 'SomeFunction',
   \ 'executable': 'echo',
   \})
-  AssertEqual 'Either `command`, `executable_callback`, `command_chain` must be defined', g:vader_exception
+  AssertEqual '`command` must be defined', g:vader_exception
 
 Execute (PreProcess should throw when command is not a string):
   AssertThrows call ale#linter#PreProcess('testft', {
@@ -98,15 +89,6 @@ Execute (PreProcess should allow command to be a callback):
   \ 'command': function('type'),
   \})
 
-Execute (PreProcess should throw when command_callback is not a callback):
-  AssertThrows call ale#linter#PreProcess('testft', {
-  \ 'name': 'foo',
-  \ 'callback': 'SomeFunction',
-  \ 'executable': 'echo',
-  \ 'command_callback': 123,
-  \})
-  AssertEqual '`command_callback` must be a callback if defined', g:vader_exception
-
 Execute (PreProcess should when the output stream isn't a valid string):
   AssertThrows call ale#linter#PreProcess('testft', {
   \ 'name': 'foo',
@@ -152,117 +134,12 @@ Execute (PreProcess should accept a 'both' output_stream):
   \ 'output_stream': 'both',
   \})
 
-Execute(PreProcess should complain if the command_chain is not a List):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'callback': 'x',
-  \ 'executable': 'x',
-  \ 'command_chain': 'x',
-  \}
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual '`command_chain` must be a List', g:vader_exception
-
-Execute(PreProcess should complain if the command_chain is empty):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'callback': 'x',
-  \ 'executable': 'x',
-  \ 'command_chain': [],
-  \}
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual '`command_chain` must contain at least one item', g:vader_exception
-
-Execute(PreProcess should complain if the command_chain has no callback):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'callback': 'x',
-  \ 'executable': 'x',
-  \ 'command_chain': [{}],
-  \}
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual 'The `command_chain` item 0 must define a `callback` function', g:vader_exception
-
-Execute(PreProcess should complain if the command_chain callback is not a function):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'callback': 'x',
-  \ 'executable': 'x',
-  \ 'command_chain': [{'callback': 2}],
-  \}
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual 'The `command_chain` item 0 must define a `callback` function', g:vader_exception
-
-Execute(PreProcess should accept a chain with one callback):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'callback': 'x',
-  \ 'executable': 'x',
-  \ 'command_chain': [{'callback': 'foo'}],
-  \}
-  call ale#linter#PreProcess('testft', g:linter)
-
-Execute(PreProcess should complain about invalid output_stream values in the chain):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'callback': 'x',
-  \ 'executable': 'x',
-  \ 'command_chain': [{'callback': 'foo', 'output_stream': ''}],
-  \}
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual "The `command_chain` item 0 `output_stream` flag must be 'stdout', 'stderr', or 'both'", g:vader_exception
-
-Execute(PreProcess should complain about valid output_stream values in the chain):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'callback': 'x',
-  \ 'executable': 'x',
-  \ 'command_chain': [{'callback': 'foo', 'output_stream': 'stdout'}],
-  \}
-  call ale#linter#PreProcess('testft', g:linter)
-  let g:linter.command_chain[0].output_stream = 'stderr'
-  call ale#linter#PreProcess('testft', g:linter)
-  let g:linter.command_chain[0].output_stream = 'both'
-  call ale#linter#PreProcess('testft', g:linter)
-
-Execute(PreProcess should complain about invalid chain items at higher indices):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'callback': 'x',
-  \ 'executable': 'x',
-  \ 'command_chain': [{'callback': 'foo'}, {'callback': 123}],
-  \}
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual 'The `command_chain` item 1 must define a `callback` function', g:vader_exception
-
-Execute(PreProcess should complain when conflicting command options are used):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'callback': 'x',
-  \ 'executable': 'x',
-  \ 'command': 'foo',
-  \ 'command_chain': [{'callback': 'foo'}],
-  \}
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual 'Only one of `command`, `command_callback`, or `command_chain` should be set', g:vader_exception
-
-  unlet g:linter.command
-  let g:linter.command_callback = 'foo'
-
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual 'Only one of `command`, `command_callback`, or `command_chain` should be set', g:vader_exception
-
-  let g:linter.command = 'foo'
-  unlet g:linter.command_chain
-
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual 'Only one of `command`, `command_callback`, or `command_chain` should be set', g:vader_exception
-
 Execute(PreProcess should process the read_buffer option correctly):
   let g:linter = {
   \ 'name': 'x',
   \ 'callback': 'x',
   \ 'executable': 'x',
-  \ 'command_chain': [{'callback': 'foo'}, {'callback': 'bar'}],
+  \ 'command': 'x',
   \ 'read_buffer': '0',
   \}
 
@@ -277,25 +154,6 @@ Execute(PreProcess should process the read_buffer option correctly):
 
   call ale#linter#PreProcess('testft', g:linter)
 
-  unlet g:linter.read_buffer
-  let g:linter.command_chain[0].read_buffer = '0'
-
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual 'The `command_chain` item 0 value for `read_buffer` must be `0` or `1`', g:vader_exception
-
-  let g:linter.command_chain[0].read_buffer = 0
-
-  call ale#linter#PreProcess('testft', g:linter)
-
-  let g:linter.command_chain[1].read_buffer = '0'
-
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual 'The `command_chain` item 1 value for `read_buffer` must be `0` or `1`', g:vader_exception
-
-  let g:linter.command_chain[1].read_buffer = 1
-
-  call ale#linter#PreProcess('testft', g:linter)
-
 Execute(PreProcess should set a default value for read_buffer):
   let g:linter = {
   \ 'name': 'x',
@@ -394,151 +252,96 @@ Execute(PreProcess should accept tsserver LSP configuration):
   \ 'executable': 'x',
   \ 'command': 'x',
   \ 'lsp': 'tsserver',
-  \ 'language_callback': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'language': 'x',
+  \ 'project_root': 'x',
   \}
 
   AssertEqual 'tsserver', ale#linter#PreProcess('testft', g:linter).lsp
 
-  call remove(g:linter, 'executable')
-  let g:linter.executable_callback = 'X'
-
-  call ale#linter#PreProcess('testft', g:linter)
-
-  call remove(g:linter, 'command')
-  let g:linter.command_callback = 'X'
-
-  call ale#linter#PreProcess('testft', g:linter)
-
 Execute(PreProcess should accept stdio LSP configuration):
   let g:linter = {
   \ 'name': 'x',
   \ 'executable': 'x',
   \ 'command': 'x',
   \ 'lsp': 'stdio',
-  \ 'language_callback': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'language': 'x',
+  \ 'project_root': 'x',
   \}
 
   AssertEqual 'stdio', ale#linter#PreProcess('testft', g:linter).lsp
 
-  call remove(g:linter, 'executable')
-  let g:linter.executable_callback = 'X'
-
-  call ale#linter#PreProcess('testft', g:linter)
-
-  call remove(g:linter, 'command')
-  let g:linter.command_callback = 'X'
-
-  call ale#linter#PreProcess('testft', g:linter)
-
 Execute(PreProcess should accept LSP server configurations):
   let g:linter = {
   \ 'name': 'x',
   \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
-  \ 'language_callback': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'address': 'X',
+  \ 'language': 'foobar',
+  \ 'project_root': 'x',
   \}
 
   AssertEqual 'socket', ale#linter#PreProcess('testft', g:linter).lsp
 
-Execute(PreProcess should accept let you specify the language as just a string):
+Execute(PreProcess should accept let you specify the `language` as a Function):
   let g:linter = {
   \ 'name': 'x',
   \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
-  \ 'language': 'foobar',
-  \ 'project_root_callback': 'x',
+  \ 'address': 'X',
+  \ 'language': {-> 'foobar'},
+  \ 'project_root': 'x',
   \}
 
-  AssertEqual 'foobar', ale#linter#PreProcess('testft', g:linter).language_callback(0)
-
-Execute(PreProcess should complain about using language and language_callback together):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
-  \ 'language': 'x',
-  \ 'language_callback': 'x',
-  \ 'project_root_callback': 'x',
-  \}
-
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual 'Only one of `language` or `language_callback` should be set', g:vader_exception
+  AssertEqual 'foobar', ale#linter#PreProcess('testft', g:linter).language(bufnr(''))
 
 Execute(PreProcess should complain about invalid language values):
   let g:linter = {
   \ 'name': 'x',
   \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
+  \ 'address': 'X',
   \ 'language': 0,
-  \ 'project_root_callback': 'x',
+  \ 'project_root': 'x',
   \}
 
   AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual '`language` must be a String or Funcref', g:vader_exception
+  AssertEqual '`language` must be a String or Funcref if defined', g:vader_exception
 
 Execute(PreProcess should use the filetype as the language string by default):
   let g:linter = {
   \ 'name': 'x',
   \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
-  \ 'project_root_callback': 'x',
+  \ 'address': 'X',
+  \ 'project_root': 'x',
   \}
 
-  AssertEqual 'testft', ale#linter#PreProcess('testft', g:linter).language_callback(0)
+  AssertEqual 'testft', ale#linter#PreProcess('testft', g:linter).language
 
-Execute(PreProcess should allow language to be set to a callback):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
-  \ 'language': {-> 'foo'},
-  \ 'project_root_callback': 'x',
-  \}
-
-  AssertEqual 'foo', ale#linter#PreProcess('testft', g:linter).language_callback(0)
-
-Execute(PreProcess should require an address_callback for LSP socket configurations):
+Execute(PreProcess should require an `address` for LSP socket configurations):
   let g:linter = {
   \ 'name': 'x',
   \ 'lsp': 'socket',
   \}
 
   AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual '`address` or `address_callback` must be defined for getting the LSP address', g:vader_exception
+  AssertEqual '`address` must be defined for getting the LSP address', g:vader_exception
 
-Execute(PreProcess should complain about address_callback for non-LSP linters):
+Execute(PreProcess should complain about `address` for non-LSP linters):
   let g:linter = {
   \ 'name': 'x',
   \ 'callback': 'SomeFunction',
   \ 'executable': 'echo',
   \ 'command': 'echo',
-  \ 'address_callback': 'X',
+  \ 'address': 'X',
   \}
 
   AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual '`address` or `address_callback` cannot be used when lsp != ''socket''', g:vader_exception
+  AssertEqual '`address` cannot be used when lsp != ''socket''', g:vader_exception
 
-Execute(PreProcess accept valid address_callback values):
-  let g:linter = ale#linter#PreProcess('testft', {
-  \ 'name': 'x',
-  \ 'lsp': 'socket',
-  \ 'address_callback': {-> 'foo:123'},
-  \ 'language': 'x',
-  \ 'project_root_callback': 'x',
-  \})
-
-  AssertEqual 'foo:123', ale#linter#GetAddress(0, g:linter)
-
-Execute(PreProcess accept address as a String):
+Execute(PreProcess accept `address` as a String):
   let g:linter = ale#linter#PreProcess('testft', {
   \ 'name': 'x',
   \ 'lsp': 'socket',
   \ 'address': 'foo:123',
   \ 'language': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'project_root': 'x',
   \})
 
   AssertEqual 'foo:123', ale#linter#GetAddress(0, g:linter)
@@ -549,7 +352,7 @@ Execute(PreProcess accept address as a Function):
   \ 'lsp': 'socket',
   \ 'address': {-> 'foo:123'},
   \ 'language': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'project_root': 'x',
   \})
 
   AssertEqual 'foo:123', ale#linter#GetAddress(0, g:linter)
@@ -560,11 +363,11 @@ Execute(PreProcess should complain about invalid address values):
   \ 'lsp': 'socket',
   \ 'address': 0,
   \ 'language': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'project_root': 'x',
   \})
   AssertEqual '`address` must be a String or Function if defined', g:vader_exception
 
-Execute(PreProcess should accept allow the project root be set as a String):
+Execute(PreProcess should allow the `project_root` to be set as a String):
   let g:linter = ale#linter#PreProcess('testft', {
   \ 'name': 'x',
   \ 'lsp': 'socket',
@@ -575,7 +378,7 @@ Execute(PreProcess should accept allow the project root be set as a String):
 
   AssertEqual '/foo/bar', ale#lsp_linter#FindProjectRoot(0, g:linter)
 
-Execute(PreProcess should accept allow the project root be set as a Function):
+Execute(PreProcess should `project_root` be set as a Function):
   let g:linter = ale#linter#PreProcess('testft', {
   \ 'name': 'x',
   \ 'lsp': 'socket',
@@ -586,7 +389,7 @@ Execute(PreProcess should accept allow the project root be set as a Function):
 
   AssertEqual '/foo/bar', ale#lsp_linter#FindProjectRoot(0, g:linter)
 
-Execute(PreProcess should complain when the project_root valid is invalid):
+Execute(PreProcess should complain when `project_root` is invalid):
   AssertThrows call ale#linter#PreProcess('testft', {
   \ 'name': 'x',
   \ 'lsp': 'socket',
@@ -594,154 +397,74 @@ Execute(PreProcess should complain when the project_root valid is invalid):
   \ 'language': 'x',
   \ 'project_root': 0,
   \})
-  AssertEqual '`project_root` must be a String or Function if defined', g:vader_exception
+  AssertEqual '`project_root` must be a String or Function', g:vader_exception
 
-Execute(PreProcess should accept project_root_callback as a String):
-  call ale#linter#PreProcess('testft', {
-  \ 'name': 'x',
-  \ 'lsp': 'socket',
-  \ 'address': 'foo:123',
-  \ 'language': 'x',
-  \ 'project_root_callback': 'Foobar',
-  \})
-
-Execute(PreProcess should accept project_root_callback as a Function):
-  let g:linter = ale#linter#PreProcess('testft', {
-  \ 'name': 'x',
-  \ 'lsp': 'socket',
-  \ 'address': 'foo:123',
-  \ 'language': 'x',
-  \ 'project_root_callback': {-> '/foo/bar'},
-  \})
-
-  AssertEqual '/foo/bar', ale#lsp_linter#FindProjectRoot(0, g:linter)
-
-Execute(PreProcess should complain when the project_root_callback valid is invalid):
-  AssertThrows call ale#linter#PreProcess('testft', {
-  \ 'name': 'x',
-  \ 'lsp': 'socket',
-  \ 'address': 'foo:123',
-  \ 'language': 'x',
-  \ 'project_root_callback': 0,
-  \})
-  AssertEqual '`project_root_callback` must be a callback if defined', g:vader_exception
-
-Execute(PreProcess should complain about using initialization_options and initialization_options_callback together):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
-  \ 'language': 'x',
-  \ 'project_root_callback': 'x',
-  \ 'initialization_options': 'x',
-  \ 'initialization_options_callback': 'x',
-  \}
-
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual 'Only one of `initialization_options` or `initialization_options_callback` should be set', g:vader_exception
-
-Execute(PreProcess should throw when initialization_options_callback is not a callback):
+Execute(PreProcess should throw when `initialization_options` is not a Dictionary or callback):
   AssertThrows call ale#linter#PreProcess('testft', {
   \ 'name': 'foo',
   \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
+  \ 'address': 'X',
   \ 'language': 'x',
-  \ 'project_root_callback': 'x',
-  \ 'initialization_options_callback': {},
-  \})
-  AssertEqual '`initialization_options_callback` must be a callback if defined', g:vader_exception
-
-Execute(PreProcess should throw when initialization_options is not a Dictionary or callback):
-  AssertThrows call ale#linter#PreProcess('testft', {
-  \ 'name': 'foo',
-  \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
-  \ 'language': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'project_root': 'x',
   \ 'initialization_options': 0,
   \})
-  AssertEqual '`initialization_options` must be a String or Function if defined', g:vader_exception
+  AssertEqual '`initialization_options` must be a Dictionary or Function if defined', g:vader_exception
 
-Execute(PreProcess should accept initialization_options as a Dictionary):
+Execute(PreProcess should accept `initialization_options` as a Dictionary):
   let g:linter = ale#linter#PreProcess('testft', {
   \ 'name': 'foo',
   \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
+  \ 'address': 'X',
   \ 'language': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'project_root': 'x',
   \ 'initialization_options': {'foo': v:true},
   \})
 
   AssertEqual {'foo': v:true}, ale#lsp_linter#GetOptions(0, g:linter)
 
-Execute(PreProcess should accept initialization_options as a Funcref):
+Execute(PreProcess should accept `initialization_options` as a Function):
   let g:linter = ale#linter#PreProcess('testft', {
   \ 'name': 'foo',
   \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
+  \ 'address': 'X',
   \ 'language': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'project_root': 'x',
   \ 'initialization_options': {-> {'foo': v:true}},
   \})
 
   AssertEqual {'foo': v:true}, ale#lsp_linter#GetOptions(0, g:linter)
 
-Execute(PreProcess should complain about using lsp_config and lsp_config_callback together):
+Execute(PreProcess should accept `lsp_config` as a Dictionary):
   let g:linter = {
   \ 'name': 'x',
   \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
+  \ 'address': 'X',
   \ 'language': 'x',
-  \ 'project_root_callback': 'x',
-  \ 'lsp_config': 'x',
-  \ 'lsp_config_callback': 'x',
-  \}
-
-  AssertThrows call ale#linter#PreProcess('testft', g:linter)
-  AssertEqual 'Only one of `lsp_config` or `lsp_config_callback` should be set', g:vader_exception
-
-Execute(PreProcess should throw when lsp_config_callback is not a callback):
-  AssertThrows call ale#linter#PreProcess('testft', {
-  \ 'name': 'foo',
-  \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
-  \ 'language': 'x',
-  \ 'project_root_callback': 'x',
-  \ 'lsp_config_callback': {},
-  \})
-  AssertEqual '`lsp_config_callback` must be a callback if defined', g:vader_exception
-
-Execute(PreProcess should accept LSP configuration options via lsp_config):
-  let g:linter = {
-  \ 'name': 'x',
-  \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
-  \ 'language_callback': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'project_root': 'x',
   \ 'lsp_config': {'foo': 'bar'},
   \}
 
   AssertEqual {'foo': 'bar'}, ale#lsp_linter#GetConfig(0, g:linter)
 
-Execute(PreProcess should accept LSP configuration options via lsp_config as a function):
+Execute(PreProcess should accept `lsp_config` as a Function):
   let g:linter = {
   \ 'name': 'x',
   \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
-  \ 'language_callback': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'address': 'X',
+  \ 'language': 'x',
+  \ 'project_root': 'x',
   \ 'lsp_config': {-> {'foo': 'bar'}},
   \}
 
   AssertEqual {'foo': 'bar'}, ale#lsp_linter#GetConfig(0, g:linter)
 
-Execute(PreProcess should throw when lsp_config is not a Dictionary or Function):
+Execute(PreProcess should throw when `lsp_config` is not a Dictionary or Function):
   AssertThrows call ale#linter#PreProcess('testft', {
   \ 'name': 'foo',
   \ 'lsp': 'socket',
-  \ 'address_callback': 'X',
+  \ 'address': 'X',
   \ 'language': 'x',
-  \ 'project_root_callback': 'x',
+  \ 'project_root': 'x',
   \ 'lsp_config': 'x',
   \})
   AssertEqual '`lsp_config` must be a Dictionary or Function if defined', g:vader_exception
diff --git a/test/test_shell_detection.vader b/test/test_shell_detection.vader
index 6452287f..697054d0 100644
--- a/test/test_shell_detection.vader
+++ b/test/test_shell_detection.vader
@@ -98,6 +98,16 @@ Execute(The ksh dialect should be used for shellcheck if b:is_kornshell is 1):
 
   AssertEqual 'ksh', ale#handlers#shellcheck#GetDialectArgument(bufnr(''))
 
+Execute(The filetype should be used as the default shell type when there is no hashbang line):
+  set filetype=zsh
+  AssertEqual 'zsh', ale#handlers#sh#GetShellType(bufnr(''))
+
+  set filetype=tcsh
+  AssertEqual 'tcsh', ale#handlers#sh#GetShellType(bufnr(''))
+
+  set filetype=python
+  AssertEqual '', ale#handlers#sh#GetShellType(bufnr(''))
+
 Given(A file with /bin/ash):
   #!/bin/ash
 
diff --git a/test/test_temporary_file_management.vader b/test/test_temporary_file_management.vader
index 9fff1ace..bb735886 100644
--- a/test/test_temporary_file_management.vader
+++ b/test/test_temporary_file_management.vader
@@ -40,7 +40,7 @@ Before:
   \ 'name': 'testlinter',
   \ 'executable': has('win32') ? 'cmd' : 'echo',
   \ 'callback': 'TestCallback',
-  \ 'command_callback': 'TestCommandCallback',
+  \ 'command': function('TestCommandCallback'),
   \})
   call ale#command#ClearData()