Alternatives
Products that do what Fern, a language for defining REST APIs that compiles into OpenAPI does
Hi HN, this is Danny, Deep, and Zach. We built Fern after our previous ed tech startup failed. We were frustrated with how much time we spent writing “API code” instead of working on the actual product. We tried to use OpenAPI but we were underwhelmed - the generated code wasn’t idiomatic and it still required manual work (custom templates, scripts, manually publishing SDKs to registries). The Fern compiler takes your API as input and invokes generators that output things like: SDKs, server code, a Postman collection, and an OpenAPI spec. Some technical highlights about the compiler +…
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Nino is a radical approach to solve the app chaos problem for today's knowledge worker. I believe there are still too many tools; even using them becomes work in itself. I'm building all these apps from scratch in one place, using the same database and UI, with the flexibility to eventually support the majority of work from one "superapp." Currently there are 18 apps (called "modules") on Nino: - Database types: Sheet, Form, Calendar, Gallery, Board, Todo, List - Composition types: Doc, Slide, Drive, Notebook, Canvas, Grid, Blog, Site - Communication types: Channel, Chat, Meet I want to…
2024 · nino.app
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Hi, I made a bridge (https://github.com/fzyzcjy/flutter_rust_bridge v2.0.0) between Flutter and Rust, which auto translates syntaxes like arbitrary types, &mut, async, traits, results, closure (callback), lifetimes, etc. The goal is to make a bridge between the two, seamlessly as if working in one single language. Then, as an example, I showed how to write Rust applications with GUI by utilizing Flutter. That is discussed in the link in details. To play with it, please visit the GitHub repo, or refer to the end of the article for detailed folders and commands. When I…
2024 · cjycode.com
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Instantly generate openapi (OAS) 3.0.0 REST + GraphQL APIs
2019
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Hi Hacker News! My name is Sagar, I’m working on a startup called Speakeasy - we’re making all APIs self-service. The platform is currently in beta, but we’re independently launching this tool which you can use to generate language-idiomatic, statically-typed TS SDKs from any public OpenAPI schemas. We hope to continue iterating on this to give devs a way to easily generate high fidelity client SDKs for all the major languages. Inspiration for this product is from past experiences struggling with OpenAPI. I was originally optimistic about using the OpenAPI tools to build out our offering,…
2022 · easysdk.xyz
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Hey HN, we’re building an open specification that lets agents discover and invoke APIs with natural language, built on the OpenAPI standard. agents.json clearly defines the contract between LLMs and API as a standard that's open, observable, and replicable. Here’s a walkthrough of how it works: https://youtu.be/kby2Wdt2Dtk?si=59xGCDy48Zzwr7ND. There’s 2 parts to this: 1. An agents.json file describes how to link API calls together into outcome-based tools for LLMs. This file sits alongside an OpenAPI file. 2. The agents.json SDK loads agents.json files as tools for an LLM that…
2025 · github.com
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2025 · github.com
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Colin here, creator of Nub. I’ve had the general shape of this in mind for years. Nub runs your code with stock `node`, augmented with a `--require` preload hook[0] that adds a transpiler (oxc-powered, packaged as a Node-API add-on), registers a module resolution hook[1], and injects polyfills as needed for APIs like `Worker`, `Temporal`, etc. All purely additive, your code ultimately runs using Node’s actual engine & stdlib implementations. [0] https://nodejs.org/api/cli.html#-require-module [1]…
Jun 2026 · github.com
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GitDiagram is an open-source micro dev-tool that I made this past week Given any public GitHub repository it generates diagrams in Mermaid.js with Claude 3.5 Sonnet I extract information from the file tree and README for details and interactivity (you can click components to be taken to relevant files and directories) Also, you can replace "hub" with "diagram" in any repository URL to access its diagram I created this because I wanted to contribute to open-source projects but quickly realized their codebases are too massive for me to dig through manually, so this helps me get started I do…
2024 · gitdiagram.com
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ChunkHound’s goal is simple: local-first codebase intelligence that helps you pull deep, core-dev-level insights on demand, generate always-up-to-date docs, and scale from small repos to enterprise monorepos — while staying free + open source and provider-agnostic (VoyageAI / OpenAI / Qwen3, Anthropic / OpenAI / Gemini / Grok, and more). I’d love your feedback — and if you have, thank you for being part of the journey!
Jan 2026 · github.com
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Hey HN! We've developed OpenAPI AutoSpec, a tool for automatically generating OpenAPI specifications from localhost network traffic. It’s designed to simplify the creation of API documentation by just using your website or service, especially useful when you're pressed for time. Documenting endpoints one by one sucks. This project originated from us needing it at our past jobs when building 3rd-party integrations. It acts as a local server proxy that listens to your application’s HTTP traffic and automatically translates this into OpenAPI 3.0 specs, documenting endpoints, requests, and…
2024 · github.com
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2021 · github.com
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2023 · typeapi.org
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Hey there HN! I just wrapped up an all-day documentation spree for Instant API, a JavaScript framework for easily building web APIs that implements type safety at the HTTP interface. It uses a function-as-a-service approach combined with a slightly modified JSDoc spec to automatically enforce parameter and schema validation before HTTP requests make it through to your code. You just write comments above your endpoint functions and voila, enforced type safety contracts between your API endpoints and your developers. OpenAPI specifications are generated automatically as a byproduct of simply…
2023 · github.com
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