typescript-migration-guide

Migrate JavaScript projects to TypeScript with a three-stage progressive strategy.

2|Updated Mar 3, 2026

Search Tags:#typescript #migration #type-safety #tsconfig #gradual-typing #js-to-ts #typescript-migration

Ready to run

npx skills add https://github.com/MomoDaviluke/star-citizen-promotion --skill typescript-migration-guide

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: typescript-migration-guide
Source: https://github.com/MomoDaviluke/star-citizen-promotion/tree/main/.agents/skills/typescript-migration-guide
Command: npx skills add https://github.com/MomoDaviluke/star-citizen-promotion --skill typescript-migration-guide

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This guide helps teams migrate JavaScript projects to TypeScript progressively, reducing risk and downtime by sequencing changes and validating behavior in stages.

Core Features & Use Cases

Progressive three-stage migration strategy (allowJs → checkJs false → strict) to let existing JS code run under TS with minimal changes.
Layered tsconfig approach (base config, plus dedicated node and app configs) with practical examples for Vue 3 frontends, Express backends, and Node tooling.
JSDoc-based typing and transitional patterns to gradually add type safety when files or modules cannot be converted immediately.

Quick Start

Begin with Stage 1 by enabling allowJs and turning off checkJs, then gradually add types to key modules as you verify behavior.

Frequently Asked Questions about typescript-migration-guide

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I gradually migrate a JavaScript project to TypeScript?▼

Gradual JavaScript to TypeScript migration uses a three-stage strategy: enable allowJs, keep checkJs false, and progressively add types. This lets existing JS code run under TS with minimal changes while enforcing behavior validation in stages.

What is the best way to configure tsconfig for a Vue 3 and Express monorepo?▼

Configuring tsconfig for Vue 3 and Express uses a layered approach: a base config plus dedicated node and app configs. This provides practical isolation for frontend, backend, and Node tooling during TypeScript migration.

Can I add type safety to JavaScript files without converting them to TypeScript?▼

Yes, you can add type safety to JavaScript files without converting them by using JSDoc-based typing and transitional patterns. This intermediate approach applies type checks to modules that cannot be converted immediately.

Does TypeScript migration support CI checks to maintain stability?▼

Yes, TypeScript migration supports CI checks to maintain stability. The progressive plan enforces stability by integrating tooling, layered configuration, and continuous integration checks to validate behavior across each adoption stage.

Why does a phased adoption strategy reduce downtime when moving to TypeScript?▼

A phased adoption strategy reduces downtime by sequencing changes and validating behavior in stages. This progressive approach lets existing JavaScript run under TypeScript with minimal changes while maintaining overall project stability.