Idempotency
If you like applying Idempotency, every challenge here gives you a chance to practice it on a real industry brief.
- CodeAdvancedNew
Add Idempotency Keys to a Payment Webhook System
Read the current Go webhook-sender code and 30 days of duplicate-delivery incident logs. Design the idempotency scheme: server-generated key per event (UUID v7 — time-ordered), …
- Api Design
- Idempotency
- Webhooks
API Design and GraphQL - CodeAdvancedNew
Build a Metered-Billing System for a Usage-Based SaaS
Build an event-ingest API (Express + Redis Streams) that receives usage events with idempotency keys. Aggregate hourly into Postgres rollups using a windowed worker that survive…
- Metered Billing
- Idempotency
- Event Aggregation
Engineering Software as a Service - CodeAdvancedNew
Design a Saga Orchestrator for a Cross-Border Payments Flow
Model the payment flow as a saga: 6 forward steps + their compensations. Choose between orchestration (Temporal) and choreography (event-driven via Kafka) and defend the choice.…
- Saga Pattern
- Temporal Workflow
- Compensation Logic
Event-Driven Architecture - DesignAdvancedNew
Design an Idiomatic REST + Webhooks API for a Logistics SaaS
Read the team's draft + the public APIs of 3 reference logistics platforms (anonymized, briefing pack provided). Author a 5-page API design guideline covering URL structure (nou…
- Api Design
- Rest
- Openapi
Software Design and Design Patterns Practice your coursework on real scenarios.
Every challenge is shaped from real industry context — not generic exercises. The work mirrors what your degree prepares you for.
Why Ewance
How it works
From brief to credential, in six steps.
Step 01
Browse challenges aligned to your studies.
Step 02
Accept the one that fits your goals.
Step 03
Work through it with AI Copilot guidance.
Step 04
Submit for structured evaluation.
Step 05
Earn a verified credential.
Step 06
Add it to LinkedIn with one click.
Industry teams behind a decade of practitioner briefs
Hiring from this pool?
Sponsor a challenge and meet candidates through actual work.
Industry teams can shape briefs around the skills they hire for, then evaluate students on rubric-scored deliverables — not resumes.