Overview
What this challenge is about.
Multi-Tenant Schema Migration for a Series-B HR SaaS. Advanced challenge in code. Writing production code that solves real engineering problems, earn a block...
The Brief
What you'll do, and what you'll demonstrate.
Migrate 11 tables across 3.4 TB of multi-tenant Postgres data with per-tenant cutover, zero downtime, and reversible at every phase.
This is not a coding exercise. It is the work a software engineer does between a Jira ticket and a merged PR. That distinction matters to every hiring manager who has seen candidates solve LeetCode problems and none who have shipped production code under real constraints.
When you finish, you will have something most graduates do not: a real-world deliverable, verified by Ewance, that you can show to a hiring manager and say "I did this. Here is the proof."
Earning criteria — what you'll demonstrate
- Design a 4-phase expand-contract migration that is reversible at every step
- Backfill terabyte-scale tables without breaking replication lag SLOs
- Use shadow reads + feature flags to make cutover bounded and observable
- Document a migration playbook that the on-call team can run without authors
Program Fit
Where this fits in your program.
Sharpens the same skills your degree expects you to demonstrate.
Aligned coursework coming soon.
Skills
Skills you'll demonstrate.
Each one shows up on your verified credential.
- Multi Tenant Architecture
Apply multi tenant architecture to solve real industry problems and demonstrate production-level capability.
- Schema Migration
Apply schema migration to solve real industry problems and demonstrate production-level capability.
- Dual Write
Apply dual write to solve real industry problems and demonstrate production-level capability.
- Feature Flags
Apply feature flags to solve real industry problems and demonstrate production-level capability.
- Typescript
Write type-safe code that scales across large codebases and teams.
- Postgres
Apply postgres to solve real industry problems and demonstrate production-level capability.
Careers
Career paths this challenge builds toward
Completing this challenge demonstrates skills that transfer directly to these roles: