Fintech Payments Sandbox
A test bench for moving money — Plaid connectivity, ACH vs instant rails side by side, and a clear view of the fees hiding under each one.
Stack
Problem
Payment rails are explained in diagrams but rarely felt. I want to actually move test dollars across ACH, RTP and instant rails and watch what differs.
Idea
A sandbox app that links accounts via Plaid, initiates transfers over multiple rails, and visualizes clearing vs settlement, timing, reversibility and fees.
Why I want to build it
Everything I wrote in What Actually Happens When You Connect Your Bank With Plaid and How Instant Payments Actually Move Money deserves a hands-on companion. Reading about settlement is one thing; watching a test dollar clear and settle on different clocks is another.
Planned scope
- Link accounts through Plaid sandbox
- Initiate ACH vs RTP/FedNow transfers side by side
- Visualize clearing vs settlement timelines
- Surface the fee taken at each hop
Status
Currently mapping the architecture and the sandbox/test-credential setup before writing code. Idea stage — following the "map it before you build it" rule.