How to build a coding agent 🤖, Claude Code for design 🎨, API design tips 🎓

Claude Code can be used as a design partner by creating an initial plan document, which serves as the single source of truth ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌  ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ 

Sign Up |Advertise|View Online TLDR Together With  TLDR Web Dev 2025-08-25 👋 Goodbye low test coverage and slow QA cycles (Sponsor) Bugs sneak out when less than 80% of user flows are tested before shipping. However, getting that kind of coverage (and staying there) is hard and pricey for any team. QA Wolf's AI-native service provides high-volume, high-speed test coverage for web and mobile apps, reducing your organization's QA cycle to minutes.  They can get you: 80% automated E2E test coverage in weeks—not years Unlimited parallel test runs 24-hour maintenance and on-demand test creation Zero flakes, guaranteed The benefit? No more manual E2E testing. No more slow QA cycles. No more bugs reaching production. With QA Wolf, Drata achieved 4x more test cases and 86% faster QA cycles. ⭐ Rated 4.8/5 on G2. Schedule a demo to learn more 🧑‍💻 Articles & Tutorials How to build a coding agent: free workshop (27 minute read) Building a coding agent is surprisingly simple. It requires only around 300 lines of code and a loop with LLM tokens. Dynamically patch a Python function's source code at runtime (12 minute read) Python functions can be dynamically patched at runtime using `compile` and `exec` for building flexible AI bots. This can be used to generate and execute code with access to the current environment, enabling useful functionalities such as manipulating dataframes without pre-defined tools. However, this also has security risks, as malicious LLM outputs could harm the system. 🧠 Opinions & Advice Materialized views are obviously useful (7 minute read) Maintaining derived data, like task counts per project, is a common problem and often has complexities that arise when using caching and manual updates. Instead, "incremental view maintenance" or "differential dataflow" is a better solution. This approach involves defining desired data transformations with SQL, after which the system automatically keeps the results up-to-date. Turning Claude Code Into My Best Design Partner (6 minute read) Claude Code can be used as a design partner by creating an initial plan document, which serves as the single source of truth. The plan is a "living document," so it's constantly updated as the design gets updated, creating a collaborative design process. Everything I know about good API design (20 minute read) When designing good APIs, avoid breaking existing code and use versioning for necessary changes. The success of an API heavily relies on the product it supports, and a poorly designed product can ruin API elegance. 🚀 Launches & Tools Free Course: Technical Diagramming, AI Workflows, and More (Sponsor) Better diagramming can be your secret weapon to boost productivity. Learn technical diagramming, Agile integrations with Jira/Azure, AI-powered workflows, how to run better retrospectives, and much more in Miro Academy's curated video course — designed specifically for engineering teams. Free and ungated Unlocking Rich UI Component Rendering in AI Responses (8 minute read) react-markdown-with-mdx is a library that renders rich UI components within LLM-generated markdown using JSX. This HOC wrapper improves react-markdown to safely support JSX component tags in markdown, validating attributes with Zod. By allowing LLMs to generate JSX tags, developers can embed framework-native React components directly into AI-generated text, creating a more visually engaging and interactive UI. Sidequest (GitHub Repo) Sidequest is a modern, TypeScript-based background job processor for Node.js applications. It has features like worker threads, multiple database backends (SQLite, PostgreSQL, and MySQL), ESM/CJS support, and a web dashboard for monitoring. 🎁 Miscellaneous What makes Claude Code so damn good (and how to recreate that magic in your agent)!? (15 minute read) Claude Code is good because it's simple. It has a single main loop, simple search, and clear task management. Smaller models are great for simple tasks like parsing and summarizing, and using techniques like `claude.md` files, XML tags, and Markdown improve the outputs of Claude Code. How I Made My Online Game Work Without JavaScript and Why You Probably Shouldn't (8 minute read) This dev built an online board game website with fully optional JavaScript. They used server-side rendering with SvelteKit, standard HTML elements like `summary` and `details` for interactive components, and URL parameters for managing UI state. To mimic real-time updates without WebSockets, they used the auto-refresh meta-tag. ⚡ Quick Links Making games in Go: 3 months without LLMs vs. 3 days with LLMs (6 minute read) LLMs have made a 3-month game creation effort that takes just 3 days. AI-powered prototyping with design systems (5 minute read) AI-native design systems, like shadcn/ui, can be used to generate on-brand, production-ready prototypes by having open, composable components, token-based styling, and a registry for scaling and contextualizing design elements. Reserve First (5 minute read) Exception safety bugs in memory management code can be prevented by reserving memory before modifying data structures to avoid data corruption during allocation failures. 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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