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Top 23 API Open-Source Projects
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Project mention: 🔥 Hidden Gems on GitHub That Every Developer (IT/Non-IT) Needs to Explore | dev.to | 2025-05-30
📊 6. Public APIs 📍 https://github.com/public-apis/public-apis Why it's awesome: A massive list of free APIs for development, testing, and integration. You can use them to build apps, dashboards, or even just explore new ideas. ✅ Best For: App devs, students, startup founders 🧠 Ideas: Weather app, crypto tracker, quote bot, anime finder
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InfluxDB
InfluxDB – Built for High-Performance Time Series Workloads. InfluxDB 3 OSS is now GA. Transform, enrich, and act on time series data directly in the database. Automate critical tasks and eliminate the need to move data externally. Download now.
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So I headed over to the Neovim GitHub like any lost soul would and followed the official install steps:
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Project mention: Getting Started with FastAPI: A Beginner’s Guide Using Python 🐍 | dev.to | 2025-06-01
Official FastAPI Docs
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Project mention: These 20 Awesome API Clients Will Change How You Work with APIs | dev.to | 2025-06-11
Hoppscotch is a modern, sleek, and fast browser-based API client designed for speed and simplicity. Originally inspired by Postman, it's now a full ecosystem supporting REST, GraphQL, WebSocket, and more.
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Strapi
🚀 Strapi is the leading open-source headless CMS. It’s 100% JavaScript/TypeScript, fully customizable, and developer-first.
Project mention: SOLVED: REST API and Content Manager returning different IDs for entries | dev.to | 2025-05-29This case is not rare, you can find another case here: https://github.com/strapi/strapi/issues/21967
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Project mention: Ask HN: What are good high information density UIs (screenshots, apps, sites) | news.ycombinator.com | 2025-05-08
I find the imgui UIs to be very high density (https://github.com/ocornut/imgui and the gallery issues) See for example the tracy profiler: https://github.com/wolfpld/tracy. It seems the game dev community has pretty powerful tools to understand and interrogate their work.
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quivr
Opiniated RAG for integrating GenAI in your apps 🧠 Focus on your product rather than the RAG. Easy integration in existing products with customisation! Any LLM: GPT4, Groq, Llama. Any Vectorstore: PGVector, Faiss. Any Files. Anyway you want.
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SaaSHub
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Leverage libraries like tRPC or GraphQL with TypeScript to ensure type safety across the stack:
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ccxt
A JavaScript / TypeScript / Python / C# / PHP / Go cryptocurrency trading API with support for more than 100 bitcoin/altcoin exchanges
View the Project on GitHub
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insomnia
The open-source, cross-platform API client for GraphQL, REST, WebSockets, SSE and gRPC. With Cloud, Local and Git storage.
Project mention: Postman is logging all your secrets and environment variables | news.ycombinator.com | 2025-05-16 -
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httpie
🥧 HTTPie CLI — modern, user-friendly command-line HTTP client for the API era. JSON support, colors, sessions, downloads, plugins & more. (by httpie)
Project mention: 6 Game-Changing Postman Alternatives That Will Revolutionize Your API Development in 2025 | dev.to | 2025-05-09For developers who prefer terminal-based workflows, HTTPie offers a more user-friendly alternative to curl while maintaining the efficiency of command-line tools. Its intuitive syntax and colorized output make API testing from the terminal more accessible and productive.
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LocalAI
:robot: The free, Open Source alternative to OpenAI, Claude and others. Self-hosted and local-first. Drop-in replacement for OpenAI, running on consumer-grade hardware. No GPU required. Runs gguf, transformers, diffusers and many more models architectures. Features: Generate Text, Audio, Video, Images, Voice Cloning, Distributed, P2P inference
Project mention: Nvidia on NixOS WSL – Ollama up 24/7 on your gaming PC | news.ycombinator.com | 2025-04-10If you're going to run Ollama in Windows anyway, why not use the native build? And if you want to use WSL, then I'd sugggest using something like LocalAI which gives you a lot more control and support for additional formats (GGML, GGUF, GPTQ, ONNX, etc).
https://github.com/mudler/LocalAI
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Hasura
Blazing fast, instant realtime GraphQL APIs on all your data with fine grained access control, also trigger webhooks on database events.
Project mention: My personal favorite MCP server which has became part of my life | dev.to | 2025-05-27GitHub: github.com/hasura/graphql-engine
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Directus
The flexible backend for all your projects 🐰 Turn your DB into a headless CMS, admin panels, or apps with a custom UI, instant APIs, auth & more.
Project mention: Directus.js (JavaScript SDK) – The official client for Directus APIs | dev.to | 2025-06-11If you're working with Directus, the open-source headless CMS and data platform, then Directus.js is your new best friend.
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Project mention: Why Django REST Framework doesn't show your custom validation error messages (and what to do about it) | dev.to | 2025-05-21
The GitHub Discussion: link
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one-api
LLM API 管理 & 分发系统,支持 OpenAI、Azure、Anthropic Claude、Google Gemini、DeepSeek、字节豆包、ChatGLM、文心一言、讯飞星火、通义千问、360 智脑、腾讯混元等主流模型,统一 API 适配,可用于 key 管理与二次分发。单可执行文件,提供 Docker 镜像,一键部署,开箱即用。LLM API management & key redistribution system, unifying multiple providers under a single API. Single binary, Docker-ready, with an English UI.
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This is especially helpful because Supabase uses PostegREST under the hood, which does not support OpenAPI 3.x. Note that some Postgres specific features like enums are not converted to JSON Schema enums as Sequelize doesn't expose that information.
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openapi-generator
OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec (v2, v3)
The beta version was able to generate the expected Quote model object, but I ran into issues trying to generate an interface or abstract class that my controllers could extend. So I decided to create an issue in the openapi-generator library (link for those who are interested in the details) and pivot toward another approach.
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According to Microsoft's API design guidelines, excessive nesting makes APIs brittle and difficult to evolve. The second approach provides multiple ways to access the same data depending on the consumer's needs, improving flexibility without sacrificing clarity.
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API-Security-Checklist
Checklist of the most important security countermeasures when designing, testing, and releasing your API
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API discussion
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Directus.js (JavaScript SDK) – The official client for Directus APIs
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The AI Agent Reality Gap
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log4net VS Serilog - a user suggested alternative
3 projects | 9 Jun 2025 -
Building an AI Voice Assistant in 1 Minute (Mac Terminal)
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Self-hosting your own media considered harmful according to YouTube
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A note from our sponsor - SaaSHub
www.saashub.com | 14 Jun 2025
Index
What are some of the best open-source API projects? This list will help you:
# | Project | Stars |
---|---|---|
1 | public-apis | 350,930 |
2 | neovim | 90,252 |
3 | fastapi | 86,038 |
4 | Hoppscotch | 72,156 |
5 | Strapi | 66,977 |
6 | imgui | 66,091 |
7 | quivr | 37,970 |
8 | trpc | 37,564 |
9 | ccxt | 36,883 |
10 | insomnia | 36,534 |
11 | slate | 36,148 |
12 | httpie | 35,841 |
13 | LocalAI | 33,172 |
14 | Hasura | 31,569 |
15 | SWR | 31,566 |
16 | Directus | 30,844 |
17 | Medusa | 29,433 |
18 | django-rest-framework | 29,198 |
19 | one-api | 25,635 |
20 | postgrest | 25,387 |
21 | openapi-generator | 23,956 |
22 | api-guidelines | 23,032 |
23 | API-Security-Checklist | 22,854 |