AI unit test generators 🤖, browser MCP 🌐, 20 years of Git 📆

Tusk, Cursor Agent, and Claude Code were tested in generating unit tests for a TypeScript PR with a bug in it. Tusk is a verticalized agent ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌  ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ 

Sign Up |Advertise|View Online TLDR  TLDR Web Dev 2025-04-08 🧑‍💻 Articles & Tutorials Comparing AI Unit Test Generators on TypeScript: Tusk vs. Cursor Agent vs. Claude Code (12 minute read) Tusk, Cursor Agent, and Claude Code were tested in generating unit tests for a TypeScript PR with a bug in it. Tusk, a verticalized unit testing agent, outperformed general-purpose agents like Cursor Agent and Claude Code by detecting the bug in 90% of runs and consistently following codebase mocking patterns. While general-purpose LLMs are easily accessible, verticalized agents are better for catching edge cases and for overall reliability. Building Robust React Apps with Zustand and Immer (10 minute read) Zustand and Immer can be used for state management in React apps. Zustand is more of a minimalist state management solution, with much less boilerplate compared to Redux. Immer makes immutable state updates easy, especially with nested data. 🧠 Opinions & Advice Your Startup Doesn't Need to Be a Unicorn (7 minute read) There's a "missing middle path" for B2B SaaS startups, a fundraising strategy between the high-growth VC model and bootstrapping. Raising a small amount of capital (under $1M) while maintaining equity allows founders to build profitable, valuable assets without excessive financial risk or sacrificing too much time. Recent AI model progress feels mostly like bullshit (47 minute read) A company using AI models for security vulnerability detection found that recent AI model improvements beyond Claude 3.5-3.7 Sonnet have not improved much on its internal benchmarks or in developers' ability to find new bugs. This goes to show that current benchmarks may not accurately reflect real-world usefulness and generality, with AI labs probably overfitting to specific benchmarks. The Best Programmers I Know (10 minute read) Good programmers get knowledge from original sources like documentation, rather than relying on quick fixes from online forums. They also have a deep understanding of tools and the ability to thoroughly analyze error messages. They can break down complex problems into manageable pieces and are unafraid to dive into code. 🚀 Launches & Tools Browser MCP (Website) Browser MCP is a tool that connects AI apps to your web browser, allowing them to automate tasks, such as testing, form filling, and data collection. It runs locally and securely using your existing browser profile. Bare (GitHub Repo) Bare is a small, modular JavaScript runtime designed for desktop and mobile environments. It uses libjs and libuv for engine-independent V8 bindings and async I/O. This allows module authors to implement native addons that can run on the JavaScript engine directly. Uncurl (Website) Uncurl makes sharing curl commands easy by allowing users to paste commands, generate shareable URLs, and access them from anywhere. 🎁 Miscellaneous 20 years of Git. Still weird, still wonderful (15 minute read) Git has evolved from a small project to the dominant version control system in 20 years. It was originally created to improve patch and tarball management for Linux kernel development and was envisioned as a low-level toolset rather than a full-fledged version control system. Over time, user-friendly "porcelain" commands were created, turning Git into the tool we know today. Inside the CodeBot: A Gentle Introduction to How LLMs Understand Nullability (22 minute read) By analyzing the internal "thoughts" of LLMs as they generate code, a "nullability probe" was created to determine if a model recognizes when a variable could be null. From this, it was found that LLMs do develop an internal concept of nullability during training, although their ability to apply this understanding depends on factors like code complexity and model size. 10 Years of Netlify, from Jamstack to Agent Driven Development (4 minute read) In 10 years, Netlify popularized the Jamstack architecture and made frontend dev lives easier. Over the past decade, there has been a big shift from server-side development to frontend-focused teams, especially with the rise of tools like React and Next.js. Looking forward, AI agent-driven development will probably be the next frontend dev trend. ⚡ Quick Links Don't Mock Your Framework: Writing Tests You Won't Regret (8 minute read) Devs should avoid mocking framework dependencies directly and instead create thin adapters around libraries they control and use integration tests with real implementations. Testing Frameworks and Mini Languages (27 minute read) While using testing frameworks with domain-specific languages DSLs might seem concise, they can complicate large-scale code refactoring and programmatic maintenance due to their added complexity. TIL: Any program can be a GitHub Actions shell (2 minute read) GitHub Actions allows the `shell` keyword to be set to any executable on the `$PATH`, allowing for unexpected and potentially risky custom shell execution within workflows. Why Companies Don't Fix Bugs (4 minute read) Companies often fail to fix obvious bugs because their priorities shift a lot and they focus on profit-generating requirements over user experience. Love TLDR? Tell your friends and get rewards! Share your referral link below with friends to get free TLDR swag! https://refer.tldr.tech/d0af4569/3 Track your referrals here. 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