An opinion piece on good API design, has some good points and takeaways. Good reading material for juniors.

Internationalization isn’t just translation. It’s about formatting dates, pluralizing words, sorting names, and more, all according to specific locales. Instead of relying on heavy third-party libraries, modern JavaScript offers the Intl API — a powerful, native way to handle i18n. A quiet reminder that the web truly is worldwide.

An interesting API/Server for Typescript that makes a Postgres DB directly accessible on the client side with caching. Security model relies on permission, and data is then stored on the browser cache, but this means you could do without a backend middleware for quite a few operations. Works with an existing schema

Open-Meteo is an open-source weather API and offers free access for non-commercial use.

Mailpit is a free, open-source SMTP testing tool built with Go and Vue. It provides a modern web UI for viewing and testing emails, and includes a REST API for integration testing.

Tests an OpenAPI based on invariants.

An open source project from Mozilla that helps use multiple models seamlessly.

A simple API client (postman like) in your terminal - Julien-cpsn/ATAC

Convert OpenAPI/Swagger specifications into clean, self-contained JSON format with resolved references. Support for OpenAPI 2.0, 3.0, and 3.1.

via: https://simonwillison.net/2025/May/29/llm-tools-exa/

An open-source weather API that offers free access for non-commercial use. No API key required.

An open-source weather API that offers free access for non-commercial use. No API key required.

Generate context with up-to-date documentation for LLMs and AI code editors