Open Source APIs & Integration Tools

Alternative toApigee

Build, document, and monetize APIs from one self-hosted platform

• 2,127 GitHub stars
• Apache-2.0Licence Apache-2.0

Alternative toFirebase

Self-hosted backend with real-time API and search built in

• 1,668 GitHub stars
• Apache-2.0Licence Apache-2.0
• #BaaS

Alternative toWorkOS FGA

Run fine-grained authorization with RBAC, ABAC, and ReBAC

• 1,335 GitHub stars
• Apache-2.0Licence Apache-2.0

Alternative toStimulsoft Reports.JS

JavaScript report server with PDF, Excel, DOCX, and HTML output

• 1,322 GitHub stars
• LGPL-3.0Licence LGPL-3.0

Alternative toTavily

Open source search APIs and MCP tools for RAG and agent workflows

• 886 GitHub stars
• Apache-2.0Licence Apache-2.0
• #AI SDK

Alternative toStripe Connect

Open source payout platform for global marketplace payments

• 566 GitHub stars
• Apache-2.0Licence Apache-2.0

Alternative toAdobe PDF Services API

Open source PDF and PostScript interpreter and converter

• 294 GitHub stars

Alternative toHeyGen LiveAvatar

Talking-avatar SDK for voice AI agents, MIT-licensed, Python and Node.

• 261 GitHub stars
• MITLicence MIT
• #AI Agents

Alternative toComposio

Self-host API execution for AI agents

• 186 GitHub stars
• Apache-2.0Licence Apache-2.0
• #AI Agents

Alternative toComposio

Self-hosted API broker that routes agent calls without exposing keys

• 186 GitHub stars
• Apache-2.0Licence Apache-2.0
• #AI Agents