Computer Science
Database & Storage Challenges
Database & Storage challenges put you inside the work of designing data layers that stay fast and correct under load. You'll develop skills in Data Modeling, Database Schema design, and Domain Modeling, and you'll write SQL with JOINs & Aggregations against PostgreSQL or MySQL.
From there you'll handle the harder edges — Indexing strategy, Query optimization, Replication basics, and Multi-region writes — working through High availability & disaster recovery and Oracle database administration the way data teams actually do. Each challenge you solve earns a verified credential you can share with recruiters.
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Business Intelligence Practice your coursework on real scenarios.
Every challenge is shaped from real-world context — not generic exercises. The work mirrors what your degree prepares you for.
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Domain-Driven Design - Browse challenges
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Apply Hexagonal Architecture to a Payments Microservice
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Web Application Development Build a verifiable portfolio.
Submissions become evidence. Reviewers with shipping experience score against a rubric; the result becomes a credential anyone can verify.
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Read the current schema dump (PostgreSQL, around 28 tables, heavily denormalized) and the team's 8 most common reporting queries. Produce an entity-relationship diagram from the…
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Tune Concurrency Control on a Multi-Tenant OLTP Database
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Java EE Backend for Sustainable Fashion Marketplace
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Build an Event-Sourced Inventory System for a Warehouse
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Reason over a Climate Policy Knowledge Graph for an EU Think Tank
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Migrate a Monolithic Database to a Sharded Topology
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Design an Anti-Corruption Layer for a Legacy Hospital EHR
Map the legacy EHR's HL7 v2 message schema (ADT, ORM, ORU segments) to the new platform's domain (Patient, Encounter, Order, Result). Identify the 6-10 anti-patterns in the lega…
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Domain-Driven Design
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.
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