diff --git a/eslint.config.js b/eslint.config.js
index d1c5736c..d6ae62c5 100644
--- a/eslint.config.js
+++ b/eslint.config.js
@@ -1,3 +1,4 @@
+// @ts-expect-error
 import svelte_config from '@sveltejs/eslint-config';
 
 /** @type {import('eslint').Linter.Config[]} */
diff --git a/package.json b/package.json
index 46d4d22f..3ac0e6eb 100644
--- a/package.json
+++ b/package.json
@@ -5,7 +5,7 @@
 	"private": true,
 	"type": "module",
 	"scripts": {
-		"check": "pnpm -r check",
+		"check": "tsc --noEmit",
 		"lint": "pnpm -r lint && eslint --cache --cache-location node_modules/.eslintcache",
 		"format": "pnpm -r format",
 		"changeset:version": "changeset version && pnpm -r generate:version && git add --all",
diff --git a/packages/cli/bin.ts b/packages/cli/bin.ts
index bf364138..e8b607fb 100644
--- a/packages/cli/bin.ts
+++ b/packages/cli/bin.ts
@@ -7,6 +7,7 @@ import { create } from './index.js';
 import { dist, package_manager } from './utils.js';
 import { executeSvelteAdd } from './svelte-add.js';
 import pkg from './package.json';
+import type { TemplateTypes, Types } from './types/internal.js';
 
 run();
 
@@ -47,7 +48,8 @@ ${colors.grey(`create-svelte version ${version}`)}
 		}
 	}
 
-	const options = await p.group(
+	type A = { template: string | symbol, types: string | symbol | null }
+	const options = await p.group<A>(
 		{
 			template: (_) =>
 				p.select({
@@ -89,8 +91,8 @@ ${colors.grey(`create-svelte version ${version}`)}
 
 	await create(cwd, {
 		name: path.basename(path.resolve(cwd)),
-		template: /** @type {'default' | 'skeleton' | 'skeletonlib'} */ options.template,
-		types: /** @type {'checkjs' | 'typescript' | null} */ options.types
+		template: options.template as TemplateTypes,
+		types: options.types as Types
 	});
 
 	p.outro('Your project is ready!');
diff --git a/packages/cli/index.ts b/packages/cli/index.ts
index ceb976ab..2beca489 100644
--- a/packages/cli/index.ts
+++ b/packages/cli/index.ts
@@ -1,31 +1,28 @@
 import fs from 'node:fs';
 import path from 'node:path';
 import { mkdirp, copy, dist } from './utils.js';
+import type { Common, Condition, File, Options, Types } from './types/internal.js';
 
-/** @type {import('./types/index.js').create} */
 // eslint-disable-next-line @typescript-eslint/require-await
-export async function create(cwd, options) {
+export async function create(cwd: string, options: Options) {
 	mkdirp(cwd);
 
 	write_template_files(options.template, options.types, options.name, cwd);
 	write_common_files(cwd, options, options.name);
 }
 
-/**
- * @param {string} template
- * @param {'typescript' | 'checkjs' | null} types
- * @param {string} name
- * @param {string} cwd
- */
-function write_template_files(template, types, name, cwd) {
+function write_template_files(
+	template: string,
+	types: Types,
+	name: string,
+	cwd: string
+) {
 	const dir = dist(`templates/${template}`);
-	copy(`${dir}/assets`, cwd, (name) => name.replace('DOT-', '.'));
+	copy(`${dir}/assets`, cwd, (name: string) => name.replace('DOT-', '.'));
 	copy(`${dir}/package.json`, `${cwd}/package.json`);
 
 	const manifest = `${dir}/files.types=${types}.json`;
-	const files = /** @type {import('./types/internal.js').File[]} */ JSON.parse(
-		fs.readFileSync(manifest, 'utf-8')
-	);
+	const files = JSON.parse(fs.readFileSync(manifest, 'utf-8')) as File[];
 
 	files.forEach((file) => {
 		const dest = path.join(cwd, file.name);
@@ -35,17 +32,9 @@ function write_template_files(template, types, name, cwd) {
 	});
 }
 
-/**
- *
- * @param {string} cwd
- * @param {import('./types/internal.js').Options} options
- * @param {string} name
- */
-function write_common_files(cwd, options, name) {
+function write_common_files(cwd: string, options: Options, name: string) {
 	const shared = dist('shared.json');
-	const { files } = /** @type {import('./types/internal.js').Common} */ JSON.parse(
-		fs.readFileSync(shared, 'utf-8')
-	);
+	const { files } = JSON.parse(fs.readFileSync(shared, 'utf-8')) as Common;
 
 	const pkg_file = path.join(cwd, 'package.json');
 	const pkg = /** @type {any} */ JSON.parse(fs.readFileSync(pkg_file, 'utf-8'));
@@ -73,12 +62,7 @@ function write_common_files(cwd, options, name) {
 	fs.writeFileSync(pkg_file, JSON.stringify(pkg, null, '\t') + '\n');
 }
 
-/**
- * @param {import('./types/internal.js').Condition} condition
- * @param {import('./types/internal.js').Options} options
- * @returns {boolean}
- */
-function matches_condition(condition, options) {
+function matches_condition(condition: Condition, options: Options) {
 	if (condition === 'default' || condition === 'skeleton' || condition === 'skeletonlib') {
 		return options.template === condition;
 	}
@@ -88,11 +72,7 @@ function matches_condition(condition, options) {
 	return !!options[condition];
 }
 
-/**
- * @param {any} target
- * @param {any} source
- */
-function merge(target, source) {
+function merge(target: any, source: any) {
 	for (const key in source) {
 		if (key in target) {
 			const target_value = target[key];
@@ -116,12 +96,10 @@ function merge(target, source) {
 	}
 }
 
-/** @param {Record<string, any>} obj */
-function sort_keys(obj) {
+function sort_keys(obj: Record<string, any>) {
 	if (!obj) return;
 
-	/** @type {Record<string, any>} */
-	const sorted = {};
+	const sorted: Record<string, any> = {};
 	Object.keys(obj)
 		.sort()
 		.forEach((key) => {
@@ -137,7 +115,7 @@ function sort_keys(obj) {
  *
  * @param {import('./types/internal.js').Common['files']} files
  */
-function sort_files(files) {
+function sort_files(files: Common['files']) {
 	return files.sort((f1, f2) => {
 		const f1_more_generic =
 			f1.include.every((include) => f2.include.includes(include)) &&
@@ -151,8 +129,7 @@ function sort_files(files) {
 	});
 }
 
-/** @param {string} name */
-function to_valid_package_name(name) {
+function to_valid_package_name(name: string) {
 	return name
 		.trim()
 		.toLowerCase()
diff --git a/packages/cli/svelte-add.js b/packages/cli/svelte-add.ts
similarity index 58%
rename from packages/cli/svelte-add.js
rename to packages/cli/svelte-add.ts
index 5892b84a..a78ccc15 100644
--- a/packages/cli/svelte-add.js
+++ b/packages/cli/svelte-add.ts
@@ -1,27 +1,30 @@
 #!/usr/bin/env node
 
 import { remoteControl, executeAdders, prompts } from '@svelte-cli/core/internal';
-import { adderCategories, categories, adderIds } from '@svelte-cli/config';
+import pkg from './package.json';
+import type { Question } from '@svelte-cli/core/adder/options';
+import type {
+	AdderDetails,
+	AddersToApplySelectorParams,
+	ExecutingAdderInfo
+} from '@svelte-cli/core/adder/execute';
+import { adderCategories, categories, adderIds, type CategoryKeys } from '@svelte-cli/config';
 import { getAdderDetails } from '@svelte-cli/adders';
 
-/**
- * @param {string} cwd
- */
-export async function executeSvelteAdd(cwd) {
+export async function executeSvelteAdd(cwd: string) {
 	remoteControl.enable();
 
-	/** @type {import('@svelte-cli/core/internal').AdderDetails<Record<string, import('@svelte-cli/core/internal').Question>>[]} */
-	const adderDetails = [];
+	const adderDetails: Array<AdderDetails<Record<string, Question>>> = [];
 
 	for (const adderName of adderIds) {
 		const adder = await getAdderDetails(adderName);
+		// @ts-expect-error
 		adderDetails.push({ config: adder.config, checks: adder.checks });
 	}
 
-	/** @type {import('@svelte-cli/core/internal').ExecutingAdderInfo} */
-	const executingAdderInfo = {
-		name: 'todo-package-name-svelte-cli',
-		version: 'todo-version'
+	const executingAdderInfo: ExecutingAdderInfo = {
+		name: pkg.name,
+		version: pkg.version
 	};
 
 	await executeAdders(adderDetails, executingAdderInfo, undefined, selectAddersToApply, cwd);
@@ -29,26 +32,13 @@ export async function executeSvelteAdd(cwd) {
 	remoteControl.disable();
 }
 
-/**
- * @typedef AdderOption
- * @property {string} value
- * @property {string} label
- * @property {string} hint
- */
-
-/**
- * @param {import('@svelte-cli/core/internal').AddersToApplySelectorParams} param0
- * @returns {Promise<string[]>}
- */
-async function selectAddersToApply({ projectType, addersMetadata }) {
-	/** @type {Record<string, AdderOption[]>} */
-	const promptOptions = {};
+type AdderOption = { value: string; label: string; hint: string };
+async function selectAddersToApply({ projectType, addersMetadata }: AddersToApplySelectorParams) {
+	const promptOptions: Record<string, AdderOption[]> = {};
 
 	for (const [categoryId, adderIds] of Object.entries(adderCategories)) {
-		const typedCategoryId = /** @type {import('@svelte-cli/config').CategoryKeys} */ (categoryId);
-		const categoryDetails = categories[typedCategoryId];
-		/** @type {AdderOption[]} */
-		const options = [];
+		const categoryDetails = categories[categoryId as CategoryKeys];
+		const options: AdderOption[] = [];
 		const adders = addersMetadata.filter((x) => adderIds.includes(x.id));
 
 		for (const adder of adders) {
diff --git a/packages/cli/test/check.js b/packages/cli/test/check.ts
similarity index 89%
rename from packages/cli/test/check.js
rename to packages/cli/test/check.ts
index 62ef1382..1bc52fdc 100644
--- a/packages/cli/test/check.js
+++ b/packages/cli/test/check.ts
@@ -5,13 +5,11 @@ import { fileURLToPath } from 'node:url';
 import { promisify } from 'node:util';
 import glob from 'tiny-glob/sync.js';
 import { beforeAll, describe, test } from 'vitest';
-import { create } from '../dist/index.js';
+import { create } from '../index.js';
+import type { TemplateTypes, Types } from '../types/internal.js';
 
-/**
- * Resolve the given path relative to the current file
- * @param {string} path
- */
-const resolve_path = (path) => fileURLToPath(new URL(path, import.meta.url));
+// Resolve the given path relative to the current file
+const resolve_path = (path: string) => fileURLToPath(new URL(path, import.meta.url));
 
 // use a directory outside of packages to ensure it isn't added to the pnpm workspace
 const test_workspace_dir = resolve_path('../../../.test-tmp/create-svelte/');
@@ -57,8 +55,7 @@ beforeAll(async () => {
 	});
 }, 60000);
 
-/** @param {any} pkg */
-function patch_package_json(pkg) {
+function patch_package_json(pkg: any) {
 	Object.entries(overrides).forEach(([key, value]) => {
 		if (pkg.devDependencies?.[key]) {
 			pkg.devDependencies[key] = value;
@@ -88,14 +85,12 @@ function patch_package_json(pkg) {
  */
 const script_test_map = new Map();
 
-const templates = /** @type {Array<'default' | 'skeleton' | 'skeletonlib'>} */ (
-	fs.readdirSync('templates')
-);
+const templates = fs.readdirSync('templates') as TemplateTypes[];
 
 for (const template of templates) {
 	if (template[0] === '.') continue;
 
-	for (const types of /** @type {const} */ (['checkjs', 'typescript'])) {
+	for (const types of ['checkjs', 'typescript'] as Types[]) {
 		const cwd = path.join(test_workspace_dir, `${template}-${types}`);
 		fs.rmSync(cwd, { recursive: true, force: true });
 
diff --git a/packages/cli/types/internal.d.ts b/packages/cli/types/internal.d.ts
index f0e86222..8a3d66a6 100644
--- a/packages/cli/types/internal.d.ts
+++ b/packages/cli/types/internal.d.ts
@@ -1,7 +1,10 @@
+export type TemplateTypes = 'default' | 'skeleton' | 'skeletonlib'
+export type Types = 'typescript' | 'checkjs' | null
+
 export type Options = {
 	name: string;
-	template: 'default' | 'skeleton' | 'skeletonlib';
-	types: 'typescript' | 'checkjs' | null;
+	template: TemplateTypes;
+	types: Types;
 };
 
 export type File = {
@@ -9,7 +12,7 @@ export type File = {
 	contents: string;
 };
 
-export type Condition = 'typescript' | 'checkjs' | 'skeleton' | 'default' | 'skeletonlib';
+export type Condition = Exclude<TemplateTypes | Types, null>;
 
 export type Common = {
 	files: Array<{
diff --git a/packages/cli/vitest.config.js b/packages/cli/vitest.config.js
index 3f545141..33cdc9c7 100644
--- a/packages/cli/vitest.config.js
+++ b/packages/cli/vitest.config.js
@@ -1,5 +1,5 @@
 import { defineConfig } from 'vitest/config';
 
 export default defineConfig({
-	test: { dir: './test', include: ['*.js'] }
+	test: { dir: './test', include: ['*.ts'] }
 });
diff --git a/tsconfig.json b/tsconfig.json
index 26c62f05..f9f1c2cb 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -1,5 +1,5 @@
 {
-	"exclude": ["**/dist/**", "**/temp/**"],
+	"exclude": [ "**/dist/**", "packages/cli/templates/**", "packages/cli/shared/**", "**/temp/**" ],
 	"compilerOptions": {
 		"checkJs": true,
 		"module": "es2022",
@@ -10,6 +10,6 @@
 		"strict": true,
 		"esModuleInterop": true,
 		"verbatimModuleSyntax": true,
-		"isolatedModules": true
+		"isolatedModules": true,
 	}
 }