diff --git a/deno.jsonc b/deno.jsonc
index c82e5a1..65ccb9d 100644
--- a/deno.jsonc
+++ b/deno.jsonc
@@ -3,7 +3,8 @@
 	"lint": {
 		"include": ["src/"],
 		"rules": {
-			"tags": ["recommended"]
+			"tags": ["recommended"],
+			"exclude": ["no-explicit-any"]
 		}
 	},
 	"fmt": {
diff --git a/justfile b/justfile
index e5ae9cd..48b8680 100644
--- a/justfile
+++ b/justfile
@@ -3,24 +3,51 @@ default:
 	@just --list
 
 # Typescript checking
-check:
+check: lint
 	deno check --unstable  --all -c deno.jsonc ./src/deno/*.ts ./src/common/*.ts
 
 # Code linting
-deno-lint:
+lint:
 	deno lint
 
 # Reformat the code
 fmt:
 	deno fmt
 
+# Run tests with all the runtimes
+test: deno-test bun-test
+
+# Clean up any generated files
+clean:
+	rm -rf .deno-cover
+	rm -rf cover
+	rm -rf docs
+
+########################################################################################################################
+# Bun-specific commands
+########################################################################################################################
+
+# Test with bun
+bun-test:
+	bun test --coverage
+
 # Run with bun
 bun-run:
 	bun run ./src/scroll.ts
 
+########################################################################################################################
+# Deno-specific commands
+########################################################################################################################
+
+# Test with deno
+deno-test:
+	deno test --allow-all
+
+# Create test coverage report with deno
+deno-coverage:
+	deno test --allow-all --coverage=.deno-cover
+	deno coverage --lcov .deno-cover
+
 # Run with deno
 deno-run:
 	deno run --allow-all --allow-ffi --deny-net --deny-hrtime --unstable ./src/scroll.ts
-
-deno-test:
-	deno test --allow-all
\ No newline at end of file
diff --git a/src/bun/index.ts b/src/bun/mod.ts
similarity index 100%
rename from src/bun/index.ts
rename to src/bun/mod.ts
diff --git a/src/bun/test_base.ts b/src/bun/test_base.ts
new file mode 100644
index 0000000..c40de78
--- /dev/null
+++ b/src/bun/test_base.ts
@@ -0,0 +1,38 @@
+/**
+ * Adapt the bun test interface to the shared testing interface
+ */
+import {test as btest, expect } from 'bun:test';
+import {ITestBase} from "../common/mod";
+
+class TestBase implements ITestBase {
+	test(name: string, fn: () => void) {
+		return btest(name, fn);
+	}
+
+	assertEquals(actual: unknown, expected: unknown): void {
+		return expect(actual).toEqual(expected);
+	}
+
+	assertExists(actual: unknown): void {
+		return expect(actual).toBeDefined();
+	}
+
+	assertInstanceOf(actual: unknown, expectedType: any): void {
+		return expect(actual).toBeInstanceOf(expectedType);
+	}
+
+	assertNotEquals(actual: unknown, expected: unknown): void {
+		return expect(actual).not.toBe(expected);
+	}
+
+	assertFalse(actual: boolean): void {
+		return expect(actual).toBe(false);
+	}
+
+	assertTrue(actual: boolean): void {
+		return expect(actual).toBe(true);
+	}
+}
+
+const testBase = new TestBase();
+export default testBase;
\ No newline at end of file
diff --git a/src/common/mod.ts b/src/common/mod.ts
new file mode 100644
index 0000000..9d77c93
--- /dev/null
+++ b/src/common/mod.ts
@@ -0,0 +1,3 @@
+export * from './runtime.ts';
+export * from './strings.ts';
+export type { ITestBase } from './test_base.ts';
diff --git a/src/common/index.ts b/src/common/runtime.ts
similarity index 72%
rename from src/common/index.ts
rename to src/common/runtime.ts
index 889b459..a853207 100644
--- a/src/common/index.ts
+++ b/src/common/runtime.ts
@@ -30,7 +30,7 @@ export const getRuntime = (): RunTime => {
 /**
  * Import a runtime-specific module
  *
- * eg. to load "src/bun/index.ts", if the runtime is bun,
+ * eg. to load "src/bun/mod.ts", if the runtime is bun,
  * you can use like so `await importForRuntime('index')`;
  *
  * @param path - the path within the runtime module
@@ -49,3 +49,18 @@ export const importForRuntime = async (path: string) => {
 
 	return await import(importPath);
 };
+
+/**
+ * Import the default export for a runtime-specific module
+ * (this is just a simple wrapper of `importForRuntime`)
+ *
+ * @param path - the path within the runtime module
+ */
+export const importDefaultForRuntime = async (path: string) => {
+	const pkg = await importForRuntime(path);
+	if ('default' in pkg) {
+		return pkg.default;
+	}
+
+	return null;
+};
diff --git a/src/common/strings_test.ts b/src/common/strings_test.ts
index df92376..f4d6b1b 100644
--- a/src/common/strings_test.ts
+++ b/src/common/strings_test.ts
@@ -1,8 +1,12 @@
-import { importForRuntime } from './index.ts';
-import { chars } from './strings.ts';
+import { chars, importDefaultForRuntime, is_ascii, ITestBase } from './mod.ts';
 
-const { test, assertEquals } = await importForRuntime('test_base');
+const t: ITestBase = await importDefaultForRuntime('test_base');
 
-test('chars fn properly splits strings into unicode characters', () => {
-	assertEquals(chars('😺😸😹'), ['😺', '😸', '😹']);
+t.test('chars fn properly splits strings into unicode characters', () => {
+	t.assertEquals(chars('😺😸😹'), ['😺', '😸', '😹']);
+});
+
+t.test('is_ascii properly descerns ascii chars', () => {
+	t.assertTrue(is_ascii('asjyverkjhsdf1928374'));
+	t.assertFalse(is_ascii('😺acalskjsdf'));
 });
diff --git a/src/common/termios.ts b/src/common/termios.ts
index 66ab955..f71d173 100644
--- a/src/common/termios.ts
+++ b/src/common/termios.ts
@@ -1,4 +1,4 @@
-import { die, importForRuntime } from './index.ts';
+import { die, importForRuntime } from './mod.ts';
 
 export const STDIN_FILENO = 0;
 export const STOUT_FILENO = 1;
@@ -122,7 +122,7 @@ export const getTermios = async () => {
 			}
 
 			const oldTermiosPtr = getPointer(this.#cookedTermios);
-			let res = tcsetattr(STDIN_FILENO, TCSANOW, oldTermiosPtr);
+			const res = tcsetattr(STDIN_FILENO, TCSANOW, oldTermiosPtr);
 			if (res === -1) {
 				die('Failed to restore canonical mode.');
 			}
diff --git a/src/common/test_base.ts b/src/common/test_base.ts
new file mode 100644
index 0000000..b01e050
--- /dev/null
+++ b/src/common/test_base.ts
@@ -0,0 +1,13 @@
+/**
+ * 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/deno/index.ts b/src/deno/mod.ts
similarity index 100%
rename from src/deno/index.ts
rename to src/deno/mod.ts
diff --git a/src/deno/test_base.ts b/src/deno/test_base.ts
index c55b2aa..f34d188 100644
--- a/src/deno/test_base.ts
+++ b/src/deno/test_base.ts
@@ -1,7 +1,51 @@
-export const test = Deno.test;
-export {
-	assert,
+import { ITestBase } from '../common/mod.ts';
+
+import {
 	assertEquals,
+	assertExists,
+	assertInstanceOf,
+	AssertionError,
 	assertNotEquals,
 	assertStrictEquals,
 } from 'https://deno.land/std/assert/mod.ts';
+
+class TestBase implements ITestBase {
+	test(name: string, fn: () => void): void {
+		return Deno.test(name, fn);
+	}
+
+	assertEquals(actual: unknown, expected: unknown): void {
+		return assertEquals(actual, expected);
+	}
+
+	assertStrictEquals(actual: unknown, expected: unknown) {
+		return assertStrictEquals(actual, expected);
+	}
+
+	assertNotEquals(actual: unknown, expected: unknown): void {
+		return assertNotEquals(actual, expected);
+	}
+
+	assertExists(actual: unknown, msg?: string): void {
+		return assertExists(actual, msg);
+	}
+
+	assertInstanceOf(actual: unknown, expectedType: any): void {
+		return assertInstanceOf(actual, expectedType);
+	}
+
+	assertTrue(actual: boolean): void {
+		if (actual !== true) {
+			throw new AssertionError(`actual: "${actual}" expected to be true"`);
+		}
+	}
+
+	assertFalse(actual: boolean): void {
+		if (actual !== false) {
+			throw new AssertionError(`actual: "${actual}" expected to be false"`);
+		}
+	}
+}
+
+export const testBase = new TestBase();
+export default testBase;
diff --git a/src/scroll.ts b/src/scroll.ts
index 3cda157..30067f1 100644
--- a/src/scroll.ts
+++ b/src/scroll.ts
@@ -8,12 +8,12 @@ export enum RunTime {
 	Unknown = 'common',
 }
 
-import { importForRuntime } from './common/index.ts';
+import { importForRuntime } from './common/mod.ts';
 
 /**
  * Determine the runtime strategy, and go!
  */
 (async () => {
-	const { main } = await importForRuntime('./index.ts');
+	const { main } = await importForRuntime('./mod.ts');
 	await main();
 })();