On-Demand Data Transfer Automation

I need a small, reliable tool that lets me move data between two specific online apps whenever I choose to trigger it. The workflow is simple: I press a button (or run a script/command), the tool authenticates with each service via their public APIs, pulls the new or updated records I specify, and posts them into the matching fields on the second platform. No automatic polling or scheduled jobs are required—the transfer happens only when I launch it.

For clarity, here’s what I expect as the final hand-off:
• A working script, executable, or lightweight web page with a clear “Run Sync” action.
• Configuration file or section where I can store API keys, endpoints, and the field-mapping logic.
• Short README explaining prerequisites, setup, and how to extend the mapping if my data model changes.

If you prefer a language or framework—Python with requests, Node.js with axios, or similar—feel free to suggest what you’re fastest with, as long as it runs on macOS or in a small Docker container.

I’ll provide the two API docs and sample payloads once we start. Let me know your proposed tech stack and timeline, and we can get moving.