diff --git a/src/runner.ts b/src/runner.ts
index 8dbfaa3..b9a3f68 100644
--- a/src/runner.ts
+++ b/src/runner.ts
@@ -1,18 +1,9 @@
 import Context from './context'
+import { greenText, redText, exec, generateCachedCollectedPathFromActual } from './utils'
 
-import util from 'util'
-import childProcess from 'child_process'
 import { promises as fs, type Dirent, type PathLike } from 'fs'
 import path from 'path'
 
-function greenText(text: string): string {
-	return `\x1b[32m${text}\x1b[0m`
-}
-
-function redText(text: string): string {
-	return `\x1b[31m${text}\x1b[0m`
-}
-
 /*
  * Collects test files recursively starting from the provided root
  * path.
@@ -41,48 +32,47 @@ async function collectTests(root: string): Promise<Array<string>> {
 	return collectedHere
 }
 
-/*
- * Collects then executes test cases based on provided test files.
- */
 async function runTests(collectedPaths: Array<string>) {
-	/*
-	 * Test files are imported dynamically so the `test` functions
-	 * defined in them are run. Running the functions doesn't actually
-	 * run the test, but instead builds the catalog of
-	 * known cases, which are executed in the next step.
-	 */
-	await Promise.all(
-		collectedPaths.map(async (collectedPath) => {
-			await import(path.resolve(collectedPath))
-		}),
-	)
-
-	console.log(greenText(`Collected ${Context.collectedTests.size} cases.`))
-
-	/*
-	 * Each case collected is executed and can fail independently
-	 * of its peers.
-	 */
-	for (let entry of Context.collectedTests.entries()) {
-		const [testLabel, testCase] = entry
-		console.group(greenText(`Test: ${testLabel}`))
-		try {
-			testCase.call()
-		} catch (e) {
-			console.error(redText(`FAIL ${testLabel}`))
-			console.error(e)
-		}
-		console.groupEnd()
+	for await (const collectedPath of collectedPaths) {
+		// FIXME: This should just use `node` and transform if TS is present instead.
+		const result = await exec(`ts-node ${collectedPath}`, {})
+		console.log(result.stdout)
 	}
+}
+
+async function collectCases(collectedPaths: Array<string>) {
+	let collectedCount = 0
+
+	for await (const collectedPath of collectedPaths) {
+		// FIXME: This should just use `node` and transform if TS is present instead.
+		const result = await exec(`COLLECT=1 ts-node ${collectedPath}`, {})
+		const collectedCases = await fs.readFile(
+			`.womm-cache/${generateCachedCollectedPathFromActual(path.resolve(collectedPath))}`,
+			{ encoding: 'utf8' },
+		)
+		collectedCount += collectedCases.split('\n').length
+	}
+
+	console.log(greenText(`Collected ${collectedCount} cases`))
 } /*
  * Logic executed when running the test runner CLI.
  */
 ;(async () => {
-	console.group('Test run')
-	const collectionRoot = process.argv[2]
-	const collectedTests = await collectTests(collectionRoot)
-	runTests(collectedTests)
-	console.groupEnd()
+	const [, , collectionRoot, ...omit] = process.argv
+	try {
+		await fs.mkdir('.womm-cache')
+
+		const collectedTests = await collectTests(collectionRoot)
+
+		await collectCases(collectedTests)
+		await runTests(collectedTests)
+	} catch (e) {
+		console.group(redText('Test run failed'))
+		console.log(redText(String(e)))
+		console.groupEnd()
+	} finally {
+		await fs.rm('.womm-cache', { force: true, recursive: true })
+	}
 })().catch((e) => {
 	throw e
 })
diff --git a/src/testCaseUtils.ts b/src/testCaseUtils.ts
index 26d827e..e84e434 100644
--- a/src/testCaseUtils.ts
+++ b/src/testCaseUtils.ts
@@ -1,18 +1,38 @@
 import Context from './context'
 
+import { promises as fs } from 'fs'
+
 import expect from './expect'
+import { greenText, redText, generateCachedCollectedPathFromActual } from './utils'
+import { type TestCaseLabel, type TestCaseFunction, type TestCaseGroup } from './types'
 
-function test(label: string, testCase: any) {
-	// Hack to get the file that contains the test definition.
-	const _prepareStackTrace = Error.prepareStackTrace
-	Error.prepareStackTrace = (_, stack) => stack
-	const stack = new Error().stack?.slice(1)
-	Error.prepareStackTrace = _prepareStackTrace
+function describe(label: TestCaseLabel, testGroup: TestCaseGroup) {
+	if (process.env.COLLECT) {
+		testGroup()
+		return
+	}
 
-	const testCaseLocation = String(stack?.[0])?.match(/\(.*\)/)?.[0] ?? 'unknown'
-	Context.collectedTests.set(`${testCaseLocation}:${label}`, testCase)
+	console.group(greenText(label))
+	testGroup()
+	console.groupEnd()
+}
+
+function test(label: TestCaseLabel, testCase: TestCaseFunction): void {
+	if (process.env.COLLECT) {
+		fs.appendFile(`.womm-cache/${generateCachedCollectedPathFromActual(process.argv[1])}`, `${label}\n`)
+		return
+	}
+
+	try {
+		testCase()
+		console.log(greenText(`[PASSED] ${label}`))
+	} catch (e) {
+		console.group(redText(`[FAILED] ${label}`))
+		console.log(redText(String(e)))
+		console.groupEnd()
+	}
 }
 
 const it = test
 
-export { it, test, expect }
+export { it, test, expect, describe }
diff --git a/src/types.ts b/src/types.ts
index add379f..8e021d0 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -1,6 +1,7 @@
 export type TestCaseLabel = string
 export type TestFilePath = string
 export type TestCaseFunction = () => void
+export type TestCaseGroup = () => void
 
 export interface IContext {
 	collectedTests: Map<TestFilePath, any>
diff --git a/src/utils.ts b/src/utils.ts
new file mode 100644
index 0000000..ca35e30
--- /dev/null
+++ b/src/utils.ts
@@ -0,0 +1,16 @@
+import util from 'util'
+import childProcess from 'child_process'
+
+export const exec = util.promisify(childProcess.exec)
+
+export function generateCachedCollectedPathFromActual(path: string): string {
+	return path.replace(/[\/.]/g, '_')
+}
+
+export function greenText(text: string): string {
+	return `\x1b[32m${text}\x1b[0m`
+}
+
+export function redText(text: string): string {
+	return `\x1b[31m${text}\x1b[0m`
+}
diff --git a/tests/expect.test.ts b/tests/expect.test.ts
index 633aeb0..b488f5b 100644
--- a/tests/expect.test.ts
+++ b/tests/expect.test.ts
@@ -1,56 +1,60 @@
 import assert from 'assert'
-import { test, expect } from '../src/testCaseUtils'
+import { describe, test, expect } from '../src/testCaseUtils'
 
-test('Equality (number)', () => {
-	assert.doesNotThrow(() => expect(1).toEqual(1))
+describe('Equality', () => {
+	test('Equality (number)', () => {
+		assert.doesNotThrow(() => expect(1).toEqual(1))
+	})
+
+	test('Equality (string)', () => {
+		assert.doesNotThrow(() => expect('expectations').toEqual('expectations'))
+	})
+
+	test('Equality (boolean)', () => {
+		assert.doesNotThrow(() => expect(true).toEqual(true))
+	})
+
+	test('Equality (failed - number)', () => {
+		assert.throws(() => expect(1).toEqual(2))
+	})
+
+	test('Equality (failed - string)', () => {
+		assert.throws(() => expect('expectation').toEqual('something else'))
+	})
+
+	test('Equality (failed - boolean)', () => {
+		assert.throws(() => expect(true).toEqual(false))
+	})
 })
 
-test('Equality (string)', () => {
-	assert.doesNotThrow(() => expect('expectations').toEqual('expectations'))
-})
+describe('Identity', () => {
+	test('Identity comparison (number)', () => {
+		assert.doesNotThrow(() => expect(1).toBe(1))
+	})
 
-test('Equality (boolean)', () => {
-	assert.doesNotThrow(() => expect(true).toEqual(true))
-})
+	test('Identity comparison (boolean)', () => {
+		assert.doesNotThrow(() => expect(true).toBe(true))
+	})
 
-test('Equality (failed - number)', () => {
-	assert.throws(() => expect(1).toEqual(2))
-})
+	test('Identity comparison (string)', () => {
+		assert.doesNotThrow(() => expect('identity').toBe('identity'))
+	})
 
-test('Equality (failed - string)', () => {
-	assert.throws(() => expect('expectation').toEqual('something else'))
-})
+	test('Identity comparison (failed - number)', () => {
+		assert.throws(() => expect(1).toEqual(2))
+	})
 
-test('Equality (failed - boolean)', () => {
-	assert.throws(() => expect(true).toEqual(false))
-})
+	test('Identity comparison (failed - boolean)', () => {
+		assert.throws(() => expect(false).toBe(true))
+	})
 
-test('Identity comparison (number)', () => {
-	assert.doesNotThrow(() => expect(1).toBe(1))
-})
+	test('Identity comparison (failed - string)', () => {
+		assert.throws(() => expect('yes').toBe('no'))
+	})
 
-test('Identity comparison (boolean)', () => {
-	assert.doesNotThrow(() => expect(true).toBe(true))
-})
-
-test('Identity comparison (string)', () => {
-	assert.doesNotThrow(() => expect('identity').toBe('identity'))
-})
-
-test('Identity comparison (failed - number)', () => {
-	assert.throws(() => expect(1).toEqual(2))
-})
-
-test('Identity comparison (failed - boolean)', () => {
-	assert.throws(() => expect(false).toBe(true))
-})
-
-test('Identity comparison (failed - string)', () => {
-	assert.throws(() => expect('yes').toBe('no'))
-})
-
-test('Equality negation', () => {
-	assert.doesNotThrow(() => expect('yes').not.toEqual('no'))
+	test('Equality negation', () => {
+		assert.doesNotThrow(() => expect('yes').not.toEqual('no'))
+	})
 })
 
 test('Stacked equality negation', () => {