Event Ticket Marketplace Backend

A live ticket marketplace backend for auctions, resale, wallet accounting and partner settlement.

61%
Share of repository commits I authored (162 of 267)
2 → 1
Primary databases consolidated into PostgreSQL, with Redis retained as cache
3 roles
Separate API access for admin, client and partner roles

Role: Backend Engineer (freelance), led the v2 refactor
Period: Nov 2025 to Dec 2025
Client: TEMMPAT
Project type: Key project
Room in the 3D HQ: L3:ticket-marketplace-backend

Results

61%
Share of repository commits I authored (162 of 267)
Counted in the client repository's git history.
2 → 1
Primary databases consolidated into PostgreSQL, with Redis retained as cache
From the commit history and data models.
3 roles
Separate API access for admin, client and partner roles
From the route middleware and commit history.

Problem

TEMMPAT supports buying, reselling and auctioning concert and event tickets. Its v1 backend split data between MongoDB and PostgreSQL without clear layers. The business needed dependable escrow-style payments, refunds and partner payouts.

Contribution

I moved the Express API to Bun with a repository pattern and consolidated data in PostgreSQL, retiring MongoDB. I added Redis caching with explicit invalidation.
I prevented double-selling by rewriting checkout and auction orders as database transactions with row locks and stock reservation.
I built wallets with a transaction ledger, multi-component platform fees, signature-verified payment callbacks, refunds and withdrawals, with partner share settlement on order completion.
I added Socket.IO buyer-seller chatrooms that open after payment, plus admin review of ticket files and signatures.
I separated admin, client and partner access, added security logging and configured Prometheus and Grafana with blackbox and PostgreSQL exporters.