You don't have to sell your soul to make money from open source. Use the "Open Core" model: keep the code free, but charge for the API-powered value you add on top.
The smartest developers aren't just writing code; they are building integrations. By connecting your open-source project to premium APIs, you can offer features that enterprises are happy to pay for, while keeping the core functionality free for the community.
Here are the 5 best APIs to integrate if you want to turn your repository into a revenue stream.
This is non-negotiable. If you want to make money, you need to accept it. Don't build your own billing system. Use Stripe to handle subscriptions for your "Pro" tier.
How to Monetize: Offer a hosted version of your repo. The code is free on GitHub, but the hosted SaaS version (with one-click deploy) costs $19/mo.
Add "Magic" to your tool. If your open-source project is a CLI tool, dashboard, or editor, integrating GPT-4 allows you to charge for "AI Assistance."
How to Monetize: Keep the manual tools free. Charge a usage-based fee for AI features like "Auto-Generate Config," "Explain Error," or "Write Documentation."
The number one feature enterprises pay for is Single Sign-On (SSO). They need to manage employee access securely. Auth0 (or Clerk) makes this trivial to add.
How to Monetize: Your standard login (Email/Password) is free. But if a company wants to enforce "Log in with Okta" or "Google Workspace," that is a $99/mo Enterprise feature.
Open source projects often fail at sending emails because setting up SMTP servers is a nightmare. Resend provides a developer-first API for transactional emails.
How to Monetize: If your tool is a monitoring system, CRON job manager, or status page, charge for "Email Alerts." The dashboard is free, but getting notified when it breaks costs money.
Data is valuable. If your tool relies on external data (SEO, e-commerce, social media), managing proxies is hard. ScrapingBee handles the blocking for you.
How to Monetize: Build a tool that analyzes websites. The "Local" version requires the user to manage their own IP (and get blocked). The "Cloud" version uses ScrapingBee to guarantee data delivery, for a monthly fee.
You don't need to close your source code to make money. You just need to offer convenience, security, and intelligence on top of it. These APIs are the building blocks of that value.