Cloud POS
Point of sale with a Python backend, running real transactions
Role: Sole engineer — React frontend, FastAPI backend, MongoDB schema, deployment. · Updated 2026-09-01
What's actually in it
The problem
The operator was running the till on paper and reconciling at close. Stock counts drifted, expenses went unrecorded, and there was no way to answer 'what sold today' without counting receipts.
What I built
- 01Built the till interface first — product grid, live cart, and checkout — because if the point of sale is slow the rest of the system never gets used.
- 02FastAPI + MongoDB backend, with boto3 for object storage and cryptography for credential handling.
- 03Order history with full line-item detail, so a dispute is resolved from the record rather than from memory.
- 04Expense tracking in the same system as revenue, so the dashboard KPIs are actual margin and not just gross takings.
- 05Dashboard built on the real transaction stream — the numbers on screen are what the shop actually did.
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Walkthroughs
The developer POV video is the one worth your time — it walks the dependency graph, the route map, and the data layer rather than clicking through screens.
Engineering decisions
UI primitives as the graph centre
The most-imported modules are button, card, select, and input — not feature components. For a till used under time pressure, consistency of interaction beats bespoke screens, and it keeps the whole surface restyleable from one place.
Python backend rather than serverless functions
A till needs a persistent connection and predictable latency. FastAPI on a long-lived process avoids cold starts at the exact moment a customer is standing at the counter.
Expenses in the same schema as sales
Keeping cost entry in a separate tool is how margin reporting dies. Both write to the same store so the dashboard computes net without a reconciliation step.
The product
Want something built the way Cloud POS was?
Bring the problem, not a spec. 30-minute call — I'll tell you what it actually takes to build, what I'd cut, and what it costs. No decks, no discovery phase invoice.