diff --git a/deno.jsonc b/deno.jsonc
index 65ccb9d..d9490e5 100644
--- a/deno.jsonc
+++ b/deno.jsonc
@@ -1,5 +1,4 @@
 {
-	"exclude": ["src/bun/**/*.ts"],
 	"lint": {
 		"include": ["src/"],
 		"rules": {
diff --git a/justfile b/justfile
index 48b8680..8958864 100644
--- a/justfile
+++ b/justfile
@@ -3,12 +3,7 @@ default:
 	@just --list
 
 # Typescript checking
-check: lint
-	deno check --unstable  --all -c deno.jsonc ./src/deno/*.ts ./src/common/*.ts
-
-# Code linting
-lint:
-	deno lint
+check: deno-check bun-check
 
 # Reformat the code
 fmt:
@@ -27,6 +22,10 @@ clean:
 # Bun-specific commands
 ########################################################################################################################
 
+# Check code with actual Typescript compiler
+bun-check:
+	bunx tsc
+
 # Test with bun
 bun-test:
 	bun test --coverage
@@ -39,6 +38,11 @@ bun-run:
 # Deno-specific commands
 ########################################################################################################################
 
+# Lint code and check types
+deno-check:
+	deno lint
+	deno check --unstable  --all -c deno.jsonc ./src/deno/*.ts ./src/common/*.ts
+
 # Test with deno
 deno-test:
 	deno test --allow-all
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..8ac0b9c
--- /dev/null
+++ b/package.json
@@ -0,0 +1,6 @@
+{
+	"dependencies": {},
+	"devDependencies": {
+		"bun-types": "^1.0.11"
+	}
+}
diff --git a/src/bun/ffi.ts b/src/bun/ffi.ts
index 3f0b2dc..9bbe5bd 100644
--- a/src/bun/ffi.ts
+++ b/src/bun/ffi.ts
@@ -2,6 +2,7 @@
  * This is all the nasty ffi setup for the bun runtime
  */
 import { dlopen, ptr, suffix } from 'bun:ffi';
+import { IFFI } from '../common/types.ts';
 
 const getLib = (name: string) => {
 	return dlopen(
@@ -23,7 +24,7 @@ const getLib = (name: string) => {
 	);
 };
 
-let cStdLib = { symbols: {} };
+let cStdLib: any = { symbols: {} };
 
 try {
 	cStdLib = getLib(`libc.${suffix}`);
@@ -35,5 +36,12 @@ try {
 	}
 }
 
-export const { tcgetattr, tcsetattr, cfmakeraw } = cStdLib.symbols;
-export const getPointer = ptr;
+const { tcgetattr, tcsetattr, cfmakeraw } = cStdLib.symbols;
+const BunFFI: IFFI = {
+	tcgetattr,
+	tcsetattr,
+	cfmakeraw,
+	getPointer: ptr,
+};
+
+export default BunFFI;
diff --git a/src/bun/mod.ts b/src/bun/mod.ts
index c736946..e7382dc 100644
--- a/src/bun/mod.ts
+++ b/src/bun/mod.ts
@@ -2,16 +2,8 @@
  * The main entrypoint when using Bun as the runtime
  */
 
-import { getTermios } from "../common/mod.ts";
 export * from './terminal_io.ts';
 
-export async function init() {
-	const t = await getTermios();
-
-	t.enableRawMode();
-
-	process.on('exit', () => {
-		console.info('Disabling raw mode');
-		t.disableRawMode();
-	})
-}
\ No newline at end of file
+export const onExit = (cb: () => void): void => {
+	process.on('beforeExit', cb);
+};
diff --git a/src/bun/terminal_io.ts b/src/bun/terminal_io.ts
index 0613273..5ed0798 100644
--- a/src/bun/terminal_io.ts
+++ b/src/bun/terminal_io.ts
@@ -1,6 +1,8 @@
 /**
  * Wrap the runtime-specific hook into stdin
  */
+import { ITerminalIO } from '../common/mod.ts';
+
 export async function* inputLoop() {
 	for await (const chunk of Bun.stdin.stream()) {
 		yield chunk;
@@ -12,3 +14,10 @@ export async function write(s: string): Promise<void> {
 
 	await Bun.write(Bun.stdout, buffer);
 }
+
+const BunTerminalIO: ITerminalIO = {
+	inputLoop,
+	write,
+};
+
+export default BunTerminalIO;
diff --git a/src/bun/test_base.ts b/src/bun/test_base.ts
index c40de78..95347e1 100644
--- a/src/bun/test_base.ts
+++ b/src/bun/test_base.ts
@@ -1,8 +1,8 @@
 /**
  * Adapt the bun test interface to the shared testing interface
  */
-import {test as btest, expect } from 'bun:test';
-import {ITestBase} from "../common/mod";
+import { expect, test as btest } from 'bun:test';
+import { ITestBase } from '../common/mod';
 
 class TestBase implements ITestBase {
 	test(name: string, fn: () => void) {
@@ -32,7 +32,11 @@ class TestBase implements ITestBase {
 	assertTrue(actual: boolean): void {
 		return expect(actual).toBe(true);
 	}
+
+	assertStrictEquals(actual: unknown, expected: unknown): void {
+		return expect(actual).toBe(expected);
+	}
 }
 
 const testBase = new TestBase();
-export default testBase;
\ No newline at end of file
+export default testBase;
diff --git a/src/common/mod.ts b/src/common/mod.ts
index 661957f..5743eb6 100644
--- a/src/common/mod.ts
+++ b/src/common/mod.ts
@@ -1,18 +1,23 @@
 import { importForRuntime } from './runtime.ts';
 import { Editor } from './editor.ts';
+import { getTermios } from './termios.ts';
 
 export * from './runtime.ts';
 export * from './strings.ts';
-export * from './termios.ts';
-export type { ITestBase } from './test_base.ts';
+export type * from './types.ts';
 
 const decoder = new TextDecoder();
 
 export async function main() {
-	const { inputLoop, init } = await importForRuntime('mod.ts');
+	const { inputLoop, onExit } = await importForRuntime('mod.ts');
 
-	// Set up handlers to enable/disable raw mode for each runtime
-	await init();
+	// Setup raw mode, and tear down on error or normal exit
+	const t = await getTermios();
+	t.enableRawMode();
+	onExit(() => {
+		console.info('Exit handler called, disabling raw mode');
+		t.disableRawMode();
+	});
 
 	// Create the editor itself
 	const editor = new Editor();
diff --git a/src/common/strings_test.ts b/src/common/strings_test.ts
index 9182bdf..8483ad0 100644
--- a/src/common/strings_test.ts
+++ b/src/common/strings_test.ts
@@ -1,4 +1,5 @@
-import { chars, importDefaultForRuntime, is_ascii, ITestBase } from './mod.ts';
+import { importDefaultForRuntime, ITestBase } from './mod.ts';
+import { chars, is_ascii } from './strings.ts';
 
 const t: ITestBase = await importDefaultForRuntime('test_base');
 
diff --git a/src/common/termios.ts b/src/common/termios.ts
index 5d5a3d2..48ee7b1 100644
--- a/src/common/termios.ts
+++ b/src/common/termios.ts
@@ -1,4 +1,4 @@
-import { die, importForRuntime } from './mod.ts';
+import { die, IFFI, importDefaultForRuntime } from './mod.ts';
 
 export const STDIN_FILENO = 0;
 export const STOUT_FILENO = 1;
@@ -8,26 +8,104 @@ export const TCSAFLUSH = 2;
 export const TERMIOS_SIZE = 60;
 
 /**
- * Common interface for setting Termios properties
+ * Implementation to toggle raw mode
  */
-export interface ITermios {
+class Termios {
 	/**
-	 * Are we currently in raw mode?
+	 * The ffi implementation for the current runtime
+	 * @private
 	 */
-	inRawMode: boolean;
+	#ffi: IFFI;
 
 	/**
-	 * Toggles on raw mode
+	 * Are we in raw mode?
+	 * @private
 	 */
-	enableRawMode(): void;
+	#inRawMode: boolean;
 
 	/**
-	 * Restores canonical mode
+	 * The saved version of the termios struct for cooked/canonical mode
+	 * @private
 	 */
-	disableRawMode(): void;
+	#cookedTermios: Uint8Array;
+
+	/**
+	 * The data for the termios struct we are manipulating
+	 * @private
+	 */
+	readonly #termios: Uint8Array;
+
+	/**
+	 * The pointer to the termios struct
+	 * @private
+	 */
+	readonly #ptr: any;
+
+	constructor(ffi: IFFI) {
+		this.#ffi = ffi;
+		this.#inRawMode = false;
+
+		// These are the TypedArrays linked to the raw pointer data
+		this.#cookedTermios = new Uint8Array(TERMIOS_SIZE);
+		this.#termios = new Uint8Array(TERMIOS_SIZE);
+
+		// The current pointer for C
+		this.#ptr = ffi.getPointer(this.#termios);
+	}
+
+	get inRawMode() {
+		return this.#inRawMode;
+	}
+
+	enableRawMode() {
+		if (this.#inRawMode) {
+			throw new Error('Can not enable raw mode when in raw mode');
+		}
+
+		// Get the current termios settings
+		let res = this.#ffi.tcgetattr(STDIN_FILENO, this.#ptr);
+		if (res === -1) {
+			die('Failed to get terminal settings');
+		}
+
+		// The #ptr property is pointing to the #termios TypedArray. As the pointer
+		// is manipulated, the TypedArray is as well. We will use this to save
+		// the original canonical/cooked terminal settings for disabling raw mode later.
+		// @ts-ignore: bad type definition
+		this.#cookedTermios = new Uint8Array(this.#termios, 0, 60);
+
+		// Update termios struct with (most of the) raw settings
+		this.#ffi.cfmakeraw(this.#ptr);
+
+		// @TODO: Tweak a few more terminal settings
+
+		// Actually set the new termios settings
+		res = this.#ffi.tcsetattr(STDIN_FILENO, TCSANOW, this.#ptr);
+		if (res === -1) {
+			die('Failed to update terminal settings. Can\'t enter raw mode');
+		}
+
+		this.#inRawMode = true;
+	}
+
+	disableRawMode() {
+		// Don't even bother throwing an error if we try to disable raw mode
+		// and aren't in raw mode. It just doesn't really matter.
+		if (!this.#inRawMode) {
+			return;
+		}
+
+		const oldTermiosPtr = this.#ffi.getPointer(this.#cookedTermios);
+		const res = this.#ffi.tcsetattr(STDIN_FILENO, TCSANOW, oldTermiosPtr);
+		if (res === -1) {
+			die('Failed to restore canonical mode.');
+		}
+
+		this.#inRawMode = false;
+	}
 }
 
-let termiosSingleton: ITermios | null = null;
+let termiosSingleton: Termios | null = null;
 
 export const getTermios = async () => {
 	if (termiosSingleton !== null) {
@@ -35,103 +113,8 @@ export const getTermios = async () => {
 	}
 
 	// Get the runtime-specific ffi wrappers
-	const { tcgetattr, tcsetattr, cfmakeraw, getPointer } =
-		await importForRuntime('ffi');
-
-	/**
-	 * Implementation to toggle raw mode
-	 */
-	class Termios implements ITermios {
-		/**
-		 * Are we in raw mode?
-		 * @private
-		 */
-		#inRawMode: boolean;
-
-		/**
-		 * The saved version of the termios struct for cooked/canonical mode
-		 * @private
-		 */
-		#cookedTermios: Uint8Array;
-
-		/**
-		 * The data for the termios struct we are manipulating
-		 * @private
-		 */
-		readonly #termios: Uint8Array;
-
-		/**
-		 * The pointer to the termios struct
-		 * @private
-		 */
-		readonly #ptr: any;
-
-		constructor() {
-			this.#inRawMode = false;
-
-			// These are the TypedArrays linked to the raw pointer data
-			this.#cookedTermios = new Uint8Array(TERMIOS_SIZE);
-			this.#termios = new Uint8Array(TERMIOS_SIZE);
-
-			// The current pointer for C
-			this.#ptr = getPointer(this.#termios);
-		}
-
-		get inRawMode() {
-			return this.#inRawMode;
-		}
-
-		enableRawMode() {
-			if (this.#inRawMode) {
-				throw new Error('Can not enable raw mode when in raw mode');
-			}
-
-			// Get the current termios settings
-			let res = tcgetattr(STDIN_FILENO, this.#ptr);
-			if (res === -1) {
-				die('Failed to get terminal settings');
-			}
-
-			// The #ptr property is pointing to the #termios TypedArray. As the pointer
-			// is manipulated, the TypedArray is as well. We will use this to save
-			// the original canonical/cooked terminal settings for disabling raw mode later.
-			this.#cookedTermios = new Uint8Array(this.#termios, 0, 60);
-
-			// Update termios struct with (most of the) raw settings
-			res = cfmakeraw(this.#ptr);
-			if (res === -1) {
-				die('Failed to call cfmakeraw');
-			}
-
-			// @TODO: Tweak a few more terminal settings
-
-			// Actually set the new termios settings
-			res = tcsetattr(STDIN_FILENO, TCSANOW, this.#ptr);
-			if (res === -1) {
-				die('Failed to update terminal settings. Can\'t enter raw mode');
-			}
-
-			this.#inRawMode = true;
-		}
-
-		disableRawMode() {
-			// Don't even bother throwing an error if we try to disable raw mode
-			// and aren't in raw mode. It just doesn't really matter.
-			if (!this.#inRawMode) {
-				return;
-			}
-
-			const oldTermiosPtr = getPointer(this.#cookedTermios);
-			const res = tcsetattr(STDIN_FILENO, TCSANOW, oldTermiosPtr);
-			if (res === -1) {
-				die('Failed to restore canonical mode.');
-			}
-
-			this.#inRawMode = false;
-		}
-	}
-
-	termiosSingleton = new Termios();
+	const ffi: IFFI = await importDefaultForRuntime('ffi');
+	termiosSingleton = new Termios(ffi);
 
 	return termiosSingleton;
 };
diff --git a/src/common/test_base.ts b/src/common/test_base.ts
deleted file mode 100644
index b01e050..0000000
--- a/src/common/test_base.ts
+++ /dev/null
@@ -1,13 +0,0 @@
-/**
- * The shared test interface, so tests can be run by both runtimes
- */
-export interface ITestBase {
-	test(name: string, fn: () => void): void;
-	assertEquals(actual: unknown, expected: unknown): void;
-	assertNotEquals(actual: unknown, expected: unknown): void;
-	assertStrictEquals(actual: unknown, expected: unknown): void;
-	assertExists(actual: unknown): void;
-	assertInstanceOf(actual: unknown, expectedType: any): void;
-	assertTrue(actual: boolean): void;
-	assertFalse(actual: boolean): void;
-}
diff --git a/src/common/types.ts b/src/common/types.ts
new file mode 100644
index 0000000..12356dc
--- /dev/null
+++ b/src/common/types.ts
@@ -0,0 +1,61 @@
+/**
+ * The shared test interface, so tests can be run by both runtimes
+ */
+export interface ITestBase {
+	test(name: string, fn: () => void): void;
+	assertEquals(actual: unknown, expected: unknown): void;
+	assertNotEquals(actual: unknown, expected: unknown): void;
+	assertStrictEquals(actual: unknown, expected: unknown): void;
+	assertExists(actual: unknown): void;
+	assertInstanceOf(actual: unknown, expectedType: any): void;
+	assertTrue(actual: boolean): void;
+	assertFalse(actual: boolean): void;
+}
+
+/**
+ * The native functions for terminal settings
+ */
+export interface IFFI {
+	/**
+	 * Get the existing termios settings (for canonical mode)
+	 */
+	tcgetattr(fd: number, termiosPtr: unknown): number;
+
+	/**
+	 * Update the termios settings
+	 */
+	tcsetattr(fd: number, act: number, termiosPtr: unknown): number;
+
+	/**
+	 * Update the termios pointer with raw mode settings
+	 */
+	cfmakeraw(termiosPtr: unknown): void;
+
+	/**
+	 * Convert a TypedArray to an opaque pointer for ffi calls
+	 */
+	getPointer(ta: any): unknown;
+}
+
+/**
+ * Runtime-specific IO streams
+ */
+export interface ITerminalIO {
+	/**
+	 * The generator function returning chunks of input from the stdin stream
+	 */
+	inputLoop(): AsyncGenerator<Uint8Array, void, unknown>;
+
+	/**
+	 * Pipe a string to stdout
+	 */
+	write(s: string): Promise<void>;
+}
+
+export interface IRuntime {
+	/**
+	 * Set a beforeExit/beforeUnload event handler for the runtime
+	 * @param cb - The event handler
+	 */
+	onExit(cb: () => void): void;
+}
diff --git a/src/deno/ffi.ts b/src/deno/ffi.ts
index d0c9eca..08644f4 100644
--- a/src/deno/ffi.ts
+++ b/src/deno/ffi.ts
@@ -1,8 +1,5 @@
 // Deno-specific ffi code
-
-// Determine library extension based on
-// your OS.
-// import { termiosStruct } from "../common/termios.ts";
+import { IFFI } from '../common/types.ts';
 
 let libSuffix = '';
 switch (Deno.build.os) {
@@ -36,6 +33,12 @@ const cStdLib = Deno.dlopen(
 	} as const,
 );
 
-export const { tcgetattr, tcsetattr, cfmakeraw } = cStdLib.symbols;
+const { tcgetattr, tcsetattr, cfmakeraw } = cStdLib.symbols;
+const DenoFFI: IFFI = {
+	tcgetattr,
+	tcsetattr,
+	cfmakeraw,
+	getPointer: Deno.UnsafePointer.of,
+};
 
-export const getPointer = Deno.UnsafePointer.of;
+export default DenoFFI;
diff --git a/src/deno/mod.ts b/src/deno/mod.ts
index 2279d07..fc403f2 100644
--- a/src/deno/mod.ts
+++ b/src/deno/mod.ts
@@ -1,17 +1,16 @@
 /**
  * The main entrypoint when using Deno as the runtime
  */
-import { getTermios } from '../common/mod.ts';
+import { IRuntime } from '../common/types.ts';
 
 export * from './terminal_io.ts';
 
-export async function init() {
-	const t = await getTermios();
+export const onExit = (cb: () => void): void => {
+	globalThis.addEventListener('onbeforeunload', cb);
+};
 
-	t.enableRawMode();
+const DenoRuntime: IRuntime = {
+	onExit,
+};
 
-	globalThis.onbeforeunload = (): void => {
-		console.info('Disabling raw mode');
-		t.disableRawMode();
-	};
-}
+export default DenoRuntime;
diff --git a/src/deno/terminal_io.ts b/src/deno/terminal_io.ts
index cab4cdb..ee264b7 100644
--- a/src/deno/terminal_io.ts
+++ b/src/deno/terminal_io.ts
@@ -1,3 +1,5 @@
+import { ITerminalIO } from '../common/types.ts';
+
 /**
  * Wrap the runtime-specific hook into stdin
  */
@@ -14,3 +16,10 @@ export async function write(s: string): Promise<void> {
 	await stdout.write(buffer);
 	stdout.releaseLock();
 }
+
+const DenoTerminalIO: ITerminalIO = {
+	inputLoop,
+	write,
+};
+
+export default DenoTerminalIO;
diff --git a/src/deno/test_base.ts b/src/deno/test_base.ts
index f34d188..852e809 100644
--- a/src/deno/test_base.ts
+++ b/src/deno/test_base.ts
@@ -47,5 +47,5 @@ class TestBase implements ITestBase {
 	}
 }
 
-export const testBase = new TestBase();
+const testBase = new TestBase();
 export default testBase;
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 0000000..a803573
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,19 @@
+{
+	"compilerOptions": {
+		"allowImportingTsExtensions": true,
+		"module": "esnext",
+		"moduleResolution": "bundler",
+		"moduleDetection": "force",
+		"target": "esnext",
+		"types": ["bun-types"],
+		"lib": ["ESNext"],
+		"noEmit": true,
+		"strict": true,
+		"forceConsistentCasingInFileNames": true,
+		"skipLibCheck": true,
+		"composite": true,
+		"downlevelIteration": true,
+		"allowSyntheticDefaultImports": true
+	},
+	"exclude": ["src/deno"]
+}