Progress on TypeScript 7, Advent of Code as an Excuse to Learn Zig, and Type-safe CLIs | News | Ep 46

TypeScript.fm - The Friendly Show for TypeScript Developers

News for the week of November 24, 2025: TypeScript team discusses progress on TS 7 and upcoming deprecations for TS 6. Plus, Svelte's new hydratable API. From the community: creating strongly-typed CLIs with yargs, magic union types to check characters, and how TypedArray can reduce memory usage.

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Chapters

• (00:00) - Welcome to the Show
• (05:21) - News: Progress on TypeScript 7 and Upcoming Deprecations
• (15:24) - News: Advent of Code is Live for Holiday Coding
• (17:07) - News: Svelte 5.44.0 Introduces hydratable API
• (19:18) - News: Vite+ FAQ Answers Some Common Questions
• (20:21) - News: Zed IDE Adds Better TS Error Messages
• (22:01) - News: TypeScript ESLint Will Simplify Redundant Type Unions
• (22:24) - Library Watch: Spikard, a Polyglot API Toolkit
• (23:31) - Library Watch: Type-safe CLIs with Optique
• (24:09) - Community Highlight: The Summer I Shipped Type Stripping by Marco Ippolito
• (25:51) - Community Highlight: Building Strongly Typed CLI Applications by John Reilly
• (27:10) - Community Highlight: Using Zod and TypeScript by Telerik
• (27:45) - Community Highlight: Lowercase & Uppercase Union by TypedRocks
• (28:32) - Community Highlight: Improving Bazel Type Checks with Isolated Declarations by Brad Zacher
• (29:28) - Community Highlight: Data-oriented Modeling by Aapo Alasuutari
• (32:01) - Community Highlight: Doom in TypeScript Types by Software Engineering Daily
• (32:17) - Bleet of the Week
• (32:45) - Cool Watch: Human-sized Lego Castle with 3D Printing
• (33:42) - Cool Watch: Predators (2010)
• (34:24) - Cool Watch: dotnetconf Talks
• (37:20) - The Minnesota Long Goodbye

News

• TypeScript Blog: Progress on TypeScript 7
• Advent of Code is live!
• Svelte 5.44.0 introduces `hydratable` API
• Vite+: New FAQ
• Zed v0.214.0, now with better TS Errors
• TypeScript-ESLint 8.48.0 adds type union redundancy check
• Library Watch: spikard, a polyglot API toolkit
• Library Watch: Optique 0.7.0 (via Hong Minhee)

From the Community

• Marco Ippolito: Summer I Shipped Type Stripping
• John Reilly: Yargs: statically typed builder commands (via johnnyreilly)
• Telerik: Zod + TypeScript: Schema Validation Made Easy
• TypedRocks: The Secret Power of The Lowercase & Uppercase UNION in TypeScript
• Brad Zacher: Improving Bazel TypeScript TypeChecks With IsolatedDeclarations (via Rob Palmer)
• Aapo Alasuutari: Interlude: A data-oriented model
• Software Engineering Daily: Josh and Dmitri talk about Doom in TypeScript Types

Cool Links

• Cool Watch: NFTI building a 3D printed castle
• Cool Watch: Predators (2010)
• Cool Watch: dotnetconf
• Cool Link: Aspire.dev, code-first local dev environments

Music
Seahorse Dreams by Kubbi (Spotify)