Feature
Open Source
Source code published under an open license.
113 providers
410 APIs
109 declared variants
The implementation is openly licensed and publicly readable, so integrators can audit behavior, fork, and contribute. Also changes the risk calculus on vendor continuity.
113 API providers on the APIs.io network offer open source. The highest-rated are GitLab, Umami, Outbrain, Airbyte, Buildkite.
Providers
Ranked by API Evangelist rating — Exemplar and Strong are expanded by default.
Exemplar 11 Complete, well-documented, and agent-ready
GitLabGitLab Inc. is an open-core company that develops GitLab, a DevOps software platform for building, securing...UmamiUmami is an open source, privacy-first web analytics platform that provides website traffic insights withou...OutbrainOutbrain Inc. (NASDAQ: OB), which closed its acquisition of Teads in early 2025 and now operates publicly a...AirbyteAirbyte is an open-source data integration platform that enables businesses to easily and efficiently move ...BuildkiteBuildkite is a hybrid CI/CD platform that combines a hosted control plane (pipelines.buildkite.com) with se...CumulocityCumulocity is an enterprise AIoT (Artificial Intelligence of Things) platform that connects, manages, and a...DaytonaDaytona is open-source, secure, and elastic infrastructure for running AI-generated code. Daytona sandboxes...n8nn8n is a fair-code workflow automation and iPaaS platform with AI-agent tooling. It exposes an instance-sco...FireblocksFireblocks is an institutional digital-asset and stablecoin infrastructure company providing MPC-secured cu...E2BE2B (e2b-dev) provides secure, isolated cloud sandboxes for AI agents and AI-generated code, built on a for...Microsoft Azure QuantumMicrosoft Azure Quantum is Microsoft's cloud quantum computing service — an open, multi-vendor platform tha...
Strong 15 Solid coverage with minor gaps
PaperspacePaperspace is a GPU cloud platform for AI, ML, and 3D rendering workloads, acquired by DigitalOcean in 2023...DescopeDescope is a customer and agentic identity access management (CIAM) platform founded in 2022 by veterans of...Academy Software FoundationThe Academy Software Foundation (ASWF) is a Linux Foundation project that supports open source software dev...Leonardo.AILeonardo.AI is an Australian generative-AI company (acquired by Canva in July 2024) offering a Production A...StytchStytch is an authentication and identity infrastructure provider. Its Consumer and B2B APIs cover passwordl...ThingsBoardThingsBoard is an open-source IoT platform for device connectivity, data collection, processing, and visual...AnkrAnkr is a Web3 infrastructure provider whose multichain RPC, Advanced API, liquid staking, contract automat...IBM QuantumIBM Quantum is IBM's quantum computing program — the operator of the IBM Quantum Platform (quantum.cloud.ib...Commerce LayerCommerce Layer is the headless, multi-market commerce API used by global brands to sell everywhere — web, m...PipedreamPipedream is a developer-centric integration platform providing three product lines: Workflows (code-level ...ChromaChroma (Chroma DB) is an open-source AI-native embedding database designed to make it easy to build LLM app...MewsMews is a cloud-native hospitality operating system serving 15,000+ hotels, hostels, and vacation-rental pr...ServiceTitanServiceTitan is the operating system for the trades — all-in-one field service management software for resi...Highlight (highlight.io)Highlight (highlight.io) is the open-source, full-stack monitoring platform — session replay, error monitor...NanonetsNanonets is a no-code document AI and OCR platform that combines a custom-model OCR API, pre-built document...
Developing 28 Usable, with meaningful gaps to close
Google Quantum AIGoogle Quantum AI is Google's quantum-computing research and engineering arm, building superconducting quan...HyperbolicHyperbolic is an open-access AI cloud and decentralized GPU marketplace serving 200,000+ builders with affo...WooCommerceWooCommerce is the world's most popular open-source eCommerce platform, built on WordPress. It provides a c...LichessLichess is a free, ad-free, open-source online chess server operated by a French nonprofit and powered enti...D-WaveD-Wave Quantum Inc. (NYSE: QBTS) is the leader in commercial quantum annealing computing and developer of t...VespaVespa is an open-source AI search engine, big-data serving engine, and vector database originally developed...EncoreEncore is a backend application framework and developer cloud that lets engineering teams build type-safe d...NangoNango.dev is a developer infrastructure platform that simplifies building product integrations with externa...LangWatchLangWatch is an open-source LLM observability, evaluation, and AI agent testing platform. Built around Open...1NCE1NCE is a Cologne-headquartered global IoT connectivity provider best known for the IoT Lifetime Flat — a s...CivitaiCivitai is the largest open community for Stable Diffusion, SDXL, Flux, and video AI models — hosting over ...Pocket NetworkPocket Network is the decentralized RPC layer of Web3 — a permissionless, fully open data delivery protocol...Triton OneTriton One is a high-performance Solana RPC and blockchain infrastructure provider operating globally distr...TIDALTIDAL is a high-fidelity music streaming service owned by Block (Square's parent, acquired 2021) offering H...CerbosCerbos is an open-core, language-agnostic, scalable authorization platform that decouples access control fr...PokéAPIPokéAPI (pokeapi.co) is a free, open-source RESTful and GraphQL API serving comprehensive Pokémon data — in...RedisRedis is an open source, in-memory data structure store used as a database, cache, message broker, and stre...ContinueContinue is the open-source AI code assistant for VS Code and JetBrains, distributed under Apache 2.0. The ...arXivarXiv is the open-access e-print repository operated by Cornell Tech, hosting more than two million preprin...Octopus EnergyOctopus Energy is a UK-founded retail energy supplier and the parent of Kraken Technologies, the AI-powered...BackpackBackpack is a Solana-first crypto company founded by Armani Ferrante and Tristan Yver — the same team behin...Beatoven.aiBeatoven.ai is an Indian generative-music startup (Bengaluru, founded 2021) building text-to-music and text...ConektaConekta is a Mexico-based payment processor that lets businesses accept credit and debit cards, OXXO cash v...ApiaryApiary is an API design and documentation platform, now part of Oracle Cloud Infrastructure. With 486,000+ ...TensorTensor is the Solana-native NFT marketplace and trading protocol founded by Tensor HQ and now stewarded by ...Department of Veterans Affairs (VA Lighthouse)VA Lighthouse is the US Department of Veterans Affairs' developer API platform. Published at developer.va.g...Analog DevicesAnalog Devices (ADI) is a global semiconductor company designing high-performance analog, mixed-signal, and...crates.iocrates.io is the official package registry for the Rust programming language, operated by the crates.io tea...
Thin 34 Limited public surface area
Children's Hospital of PhiladelphiaFounded in 1855 as the first hospital in the United States dedicated to the healthcare of children, Childre...TypesenseTypesense is a fast, typo-tolerant, open-source search engine designed for developer productivity. It provi...ForethoughtForethought is a San Francisco-based generative AI customer-support platform. Its multi-agent product suite...DoclingDocling is an open-source toolkit for parsing diverse document formats — PDF, DOCX, PPTX, XLSX, HTML, image...OpenHandsOpenHands (by All Hands AI, formerly OpenDevin) is an open-source autonomous coding agent platform. Ships a...PackagistPackagist is the default package repository for Composer, the PHP dependency manager. It indexes over 454,0...CHAOSSCHAOSS (Community Health Analytics in Open Source Software) is a Linux Foundation project that develops met...AgStack FoundationAgStack Foundation is a Linux Foundation project providing open-source digital infrastructure for the agric...KreaKrea is a real-time AI creative suite that lets designers, filmmakers, brand teams, and everyday creators g...Radio BrowserRadio Browser is a free, community-driven directory of internet radio stations. The project publishes a pub...SyndicaSyndica is a Solana-only infrastructure company building developer infrastructure for Web3. Its production ...ACI.devACI.dev (Aipolabs Agent-Computer Interface) is an open-source tool-calling platform that hooks AI agents in...ScenarioScenario is a Paris- and San Francisco-headquartered AI platform for game asset generation founded in 2021 ...TurborepoTurborepo is a high-performance build system for JavaScript and TypeScript codebases, built by Vercel and w...FrankfurterFrankfurter is an open-source (MIT) currency exchange rates API that blends foreign-exchange reference rate...AudiomackAudiomack is an on-demand music streaming and audio discovery platform that lets artists and creators uploa...JitsiJitsi is a collection of free and open-source projects for secure, simple, and scalable real-time video con...CieloCielo is one of the largest Brazilian card acquirers and a publicly traded company (B3:CIEL3), originally f...FormantFormant is a San Francisco–based robotics and physical-operations cloud platform that lets companies operat...ipifyipify operates two complementary IP APIs. The free Public IP Address API (api.ipify.org, api6.ipify.org, ap...Quote GardenQuote Garden is a free, open-source REST API that serves more than 75,000 famous quotes. Built by Prathames...XanaduXanadu is a Canadian photonic quantum computing company building room-temperature, fault-tolerant, scalable...Eyevinn TechnologyEyevinn Technology is a Stockholm, Sweden based video streaming consultancy and open source company special...GlamaGlama is an all-in-one AI workspace combining an MCP server marketplace and registry, a managed MCP gateway...Volvo CarsVolvo Cars is a Swedish premium automotive OEM (headquartered in Gothenburg, owned by Geely) that operates ...ApivaultApivault is an open-source directory and gateway for discovering public APIs. The platform catalogs thousan...BMW ConnectedDriveBMW ConnectedDrive is BMW Group's umbrella for connected vehicle services spanning navigation, remote servi...RenovateRenovate is an open source automated dependency update bot maintained by Mend. It scans repositories for re...Deutsche TelekomDeutsche Telekom AG is Europe's largest telecommunications operator, headquartered in Bonn, Germany, servin...FirelyFirely is an Amsterdam-based health IT company and one of the original co-developers of the HL7 FHIR (Fast ...Random User GeneratorFree random user data API for generating realistic fake user profiles with names, addresses, photos, and co...RakenRaken is a San Diego-based construction technology company providing a field-first daily reporting and fiel...McKinsey & CompanyMcKinsey & Company is the senior partner of the MBB triumvirate of global strategy and management consultin...SignifydSignifyd is an ecommerce fraud prevention, chargeback protection, and revenue optimization platform. Its Co...
Emerging 20 Early or largely undocumented
American AirlinesAmerican Airlines is one of the world's largest airlines, operating an extensive domestic and international...Cypress SemiconductorCypress Semiconductor was a US-based semiconductor company known for its PSoC programmable system-on-chip m...YarnYarn is an open-source JavaScript package manager and project manager originally created at Facebook in 201...Three.jsThree.js is an open-source JavaScript 3D library originally created by Ricardo Cabello (mrdoob) in 2010 and...CasdoorCasdoor is an open-source, AI-first identity and access management (IAM) and MCP gateway authentication ser...QuEra ComputingQuEra Computing is a Boston-based neutral-atom quantum computing company (founded 2018) that operates Aquil...SSTSST is an open source TypeScript framework for building full-stack applications on your own infrastructure....SchrödingerSchrödinger is a New York-headquartered (NASDAQ: SDGR) computational science company that develops a physic...QuantinuumQuantinuum is an integrated quantum computing company formed by the 2021 merger of Honeywell Quantum Soluti...PasqalPasqal is a French neutral-atom quantum computing company headquartered in Palaiseau, France and co-founded...pnpmpnpm is a fast, disk space efficient package manager for JavaScript and Node.js projects. It uses a content...GSKGSK plc (formerly GlaxoSmithKline, rebranded in May 2022) is a global biopharma headquartered in the United...Apache Software FoundationThe Apache Software Foundation (ASF) is a 501(c)(3) nonprofit organization that provides open source softwa...SonySony Group Corporation is a Japanese multinational spanning electronics, gaming, entertainment, image senso...CometComet is Perplexity's AI-native browser built on Chromium (Blink), integrating Perplexity Search and an age...SatellogicSatellogic is an Argentine-founded, U.S.-listed (NASDAQ: SATL) vertically integrated Earth observation comp...BoschBosch is a German multinational engineering and technology company producing automotive components, industr...Refact.aiRefact.ai is an open-source, local-first AI coding assistant and autonomous software-engineering agent buil...ChangelogChangelog is a media company and podcast network for developers covering open source and software developme...AutomatischAutomatisch is an open source business automation tool and self-hosted alternative to Zapier that connects ...
Minimal 5 Almost no public developer surface
CHIPS AllianceCHIPS Alliance is a Linux Foundation project (founded in 2019) that develops open-source hardware (silicon)...ether.fiether.fi is a non-custodial, decentralized Ethereum liquid restaking protocol where stakers retain control ...Rolls-RoyceRolls-Royce plc is a British multinational aerospace and defense company manufacturing aero engines (Trent ...OctoAIOctoAI (formerly OctoML) was a Seattle-based AI inference platform founded in 2019 as a University of Washi...WhyLabsWhyLabs was an AI observability platform focused on data and model monitoring for both classical ML and LLM...
What Providers Actually Declared
This feature is a canonical term. These are the free-text strings
providers wrote in their own apis.yml that map onto it.
100% open source under Apache 2.0 (with separate commercial license for `highlight.io/` and `enterprise/` directories)25+ open-source inference models — Llama 3.1 8B/70B/405B, Qwen 2.5, DeepSeek V3, DeepSeek R1, Hermes 3, Mistral, Llama 3.2 Vision, Qwen2-VL300+ Open Source Projects3D Scene module with custom-layer extensibility (open-source 3d-viewer-module)AGPL-3.0 Open SourceAll Google Quantum AI open-source software is Apache 2.0 licensedApache 2.0 LicenseApache 2.0 Open Source LicenseApache 2.0 open-source licensing for pytket, qnexus, lambeq, Guppy, Selene, QermitAutoChain — open-source lightweight framework for building and testing LLM agents (1.8k+ GitHub stars)Browser-side background-removal JS library and Blender texturing plugin available as open sourceCompanion BMW Car IT open-source stack (joynr, ramses, MoCOCrW, python-dlt) underpinning connected-vehicle middlewareCore: free open-source self-managedFirely .NET SDK — official open-source C# FHIR library (de-facto reference SDK)Free open-source MCP server hostingFree open-source WordPress pluginFree, ad-free, open-source online chess server operated by a French nonprofit, funded by donationsGSK Biostatistics Open SourceHosted Flow app (React) with full source available for self-hostingHosted micro frontends: checkout, cart, my-account, microstore, identity — each open-source on GitHubKrea Realtime experience with sub-50ms image generation and an open-source Realtime 14B autoregressive video model distilled from Wan 2.1 (CC BY-NC-SA 4.0)MIT licensed, no required runtime dependencies, runs in browser, Node.js, Electron, Tauri, Deno, and React NativeMIT licensed, open source on GitHub (vercel/turborepo)MIT-licensed open sourceMIT-licensed open source codebase (composer/packagist) — operated, not designed for reuseMulti-turn agent simulations with User Simulator and Judge Agents (open-source `scenario` framework)Ocean SDK — Python open-source SDK covering dimod, dwave-system, dwave-cloud-client, hybrid, samplersOfficial OpenAPI 3.1 specification published under MIT license at github.com/conekta/openapiOn-chain programs are open-source (Apache-2.0) Anchor programs published as IDLs, npm packages, and Rust cratesOpen SourceOpen Source (BSD-3-Clause)Open Source (MIT)Open Source Cloud (OSC)Open Source EcosystemOpen Source FocusOpen Source GovernanceOpen Source InfrastructureOpen Source IoTOpen Source LicensingOpen Source MIT License
Showing 40 of 109 declared variants
Work with this as data
Every feature here is available over the APIs.io API and to AI agents over MCP. Features is not yet its own endpoint on the v1 API. Reach it through catalog search and the tag graph, or the MCP server.