Case Studies

Each case study follows the same shape: Problem → Architecture → Stack → Demo → Interesting decisions → Lessons learned. Built to be cited.

★ Featured

Migrating an AppSheet CRM to Express + PostgreSQL

Replaced a no-code AppSheet CRM hitting its limits with a typed Express + PostgreSQL backend and a React front-end — without losing a single record.

Result Cut manual data-sync from ~6 hrs/week to near-zero; eliminated the daily row-count reconciliation.

  • TypeScript
  • Express
  • PostgreSQL
  • React
  • Drizzle ORM
★ Featured

Building a Multi-tenant CRM

A single Postgres-backed CRM serving multiple isolated tenants — schema-per-tenant isolation, shared application code, and zero cross-tenant data leaks.

Result 5 tenants on one codebase; isolation guaranteed by an automated property test on every PR; per-tenant export in one command.

  • TypeScript
  • Express
  • PostgreSQL
  • React
  • Drizzle ORM

Uploading 150 MB Audio Files to S3 Without Killing the Server

A direct-to-S3 multipart upload pipeline for large audio — presigned URLs, client-driven parts, and a worker that finalizes assembly. Zero bytes touch the app server.

Result Server memory flat (~120 MB) regardless of file size; ~300 MB uploads in under a minute on a 1-core box; resumable after drops.

  • TypeScript
  • Express
  • React
  • S3/R2
  • AWS SDK v3