I need a seasoned full-stack developer who can own the entire API integration layer of my web application—from planning and wiring up third-party services to delivering production-ready, well-documented endpoints. The core product is already scoped out; what’s missing is a clean, secure, and maintainable bridge between our front-end and multiple external APIs (payment, messaging, and a proprietary data feed). You will be free to work in the stack you know best, as long as the final solution is modular, thoroughly tested, and easy for future team members to extend. Bring your preferred frameworks (whether that’s Node, PHP, or Python), package managers, and CI/CD tools; I’m interested in results, not pigeonholing you into a predefined setup. Deliverables • All integration code in a private Git repo with clear commits • Postman (or similar) collection demonstrating each endpoint • Environment-specific configuration files with sensitive keys abstracted • README covering setup, deployment, and troubleshooting steps • Short video or live walkthrough proving each integration works end-to-end Acceptance criteria • No hard-coded credentials or secrets committed to source control • Consistent error handling that returns meaningful status codes and messages • Unit tests covering at least the happy path and one edge case per endpoint • Deployment passes on first run in a clean environment using only the README If this sounds like the kind of challenge you enjoy, let’s talk timelines and get you access to the repo.