TLDR DEV 2025-12-08

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TANSTACK'S OPEN. AI. SDK

TanStack AI launched this week in alpha. It features a clean architecture, deep type safety, tight ecosystem integration, and few assumptions about user platforms. While it is less production-ready than Vercel's AI SDK, TanStack AI is the more interesting bet for the future due to its architectural decisions. This post looks at both TanStack AI and Vercel AI SDK and compares their current features.

MIGRATING 6000 REACT TESTS USING AI AGENTS AND ASTS

Elio used Claude Code to migrate 970 test files (6,000+ tests) from React Testing Library v13 to v14 in just one week. Its team had Claude build a detailed migration guide first. They created an AST codemod to handle mechanical changes, then let Claude iteratively migrate 10 tests at a time while automatically running tests and checking coverage.

21 LESSONS FROM 14 YEARS AT GOOGLE

Great engineering is less about perfect code and more about understanding users, working well with people, and avoiding common traps. It's better to ship messy prototypes instead of debating perfect architectures forever, write clear code instead of clever code, and remember that your work doesn't speak for itself. People advocate for you in rooms you're not in.

MY THOUGHTS ON CLAUDE OPUS 4.5

Claude Opus 4.5 is a generational "unlock" in AI. It is the best model for both code and agents. Users should treat Opus 4.5 as a trusted coworker, use Claude Code for programming, and build impactful agents using the SDK.

it. Check out the case study

INTRODUCING VERCEL FOR PLATFORMS

Vercel for Platforms makes it easy to create and run customer projects on behalf of users. It features two platforms, Multi-Tenant and Multi-Project, that allow developers to deploy with a single codebase or many across any number of domains. Multi-Tenant Platforms allow developers to run a single codebase that serves many customers. Multi-Project Platforms allow developers to create a separate Vercel project per customer.

APPTRON

Apptron is a local-first development platform. It creates a full Linux environment inside the browser with a VS Code-based editor that developers can do whatever they want with. Apptron can be used as a development environment and editor, a sandbox for AI and experiments, an editor to publish static sites, an embeddable software playground, or as a way to run and share Linux software on the web. It is fully extendable, customizable, and self-hosted.

YOU GOTTA PUSH IF YOU WANNA PULL

Data management systems have historically been built around the notion of pull queries. This approach of pulling data works well, and it matches how people think and operate. However, there are some challenges with the approach: performance, data formats, data shape, and data location. These problems can be overcome with the help of materialized views. By materializing views incrementally and efficiently, you make your data available for pull-based querying in the right format and shape, at the right location.

I FAILED TO RECREATE THE 1996 SPACE JAM WEBSITE WITH CLAUDE

This dev tried to use Claude to precisely recreate the 1996 Space Jam website from a screenshot and assets, but found that it consistently failed to achieve pixel-perfect accuracy. Claude struggled with exact spatial positioning, admitting it couldn't measure pixel coordinates precisely. Claude's vision system likely processes images too coarsely to capture fine-grained spatial relationships.

THE ANATOMY OF A MACOS APP

This post goes over the historical evolution of macOS application anatomy.

USING LLMS AT OXIDE

Oxide encourages the use of LLMs but emphasizes that employees must always retain full human responsibility for all outputs.

WHY THE SANITIZER API IS JUST SETHTML()

Sanitizing HTML is the practice of taking a piece of HTML and removing some unwanted elements and attributes.

LESSONS FROM A SWIFT INTERVIEW

This post contains advice on Swift algorithm design and how to approach technical interviews.