June 05, 2025

Painless TSConfig Migrations | Jason Yu | 20B

34 minutes

Jason Yu (ycmjason.codes) joins us to share an open source tool he created to help teams migrate their legacy TSConfig compiler options to modern-day options painlessly and progressively. Learn about his experience implementing strict options on big teams, how it inspired his new tool, and how you can take advantage of it right now!

Chapters

(00:00) - Meet Jason Yu

(03:27) - Challenges of Migrating Legacy TypeScript

(05:44) - What is ts-migrating?

(07:01) - How Does ts-migrating Help Migrate TSConfig?

(09:05) - What Does the ts-migrating CLI Do?

(10:02) - How Do You Migrate Incrementally?

(11:16) - How Do You Get Started with ts-migrating?

(12:06) - Tackling the Migration in Small Chunks

(13:12) - How Does This Compare to Using Folder-based TSConfig?

(14:12) - What About ts-expect-error and ts-ignore Directives?

(16:25) - What About Multiple TSConfigs?

(17:34) - Are There Any Unsupported Compiler Options?

(19:28) - How Do You Build a TypeScript LSP Plugin?

(22:18) - How Will This Work with TS 7 (Go Native Port)?

(23:57) - Advice for Teams Migrating TSConfig

(25:52) - Jason's Favorite Coding Principles

(32:42) - Where to Follow Jason Online

Links

Jason’s Links: https://ycmjason.codes
Migrate your TSConfig incrementally: https://github.com/ycmjason/ts-migrating
Blog / Video: 7 Modern Use Cases of IIFE
ts-migrating Inspiration: https://github.com/allegro/typescript-strict-plugin
MS Docs: Writing a Language Service Plugin

Sponsored by Excalibur.js
Excalibur.js is the friendly TypeScript game engine for making 2D web games. Use your TypeScript or JavaScript skills to make games! Excalibur comes out-of-the-box with everything you need to make web games, like physics, sprites, animations, sound effects, input, and particles. Design your assets with tools like Aseprite and Tiled, then load them natively using first-party plugins.

Music
Seahorse Dreams by Kubbi (Spotify)

...more