Computer Science
Testing & QA Challenges
Testing & QA challenges put you behind the safety net that lets software ship with confidence. You'll develop skills in Software Testing, Unit Testing, and Automated Testing, build End-to-end testing flows, and read Coverage Reports to find the gaps that matter before users do.
From there you'll handle the harder edges — Test architecture, Test pyramid discipline, Contract testing, and Load Testing — alongside Static Analysis, AI-assisted test generation, and regulated practices like ISO 17025 calibration and CAPA workflows. Each challenge you solve earns a verified credential you can share with recruiters.
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Design a Lexer and Parser for a Customer Query Language
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Build a Secure-Coding Linter Ruleset for a Backend Team
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Open coursework Develop in-demand professional skills.
Each challenge names the skills it strengthens. Over time, your profile fills with the competences a hiring manager would actually look for.
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Design TaskFlow's Pricing-Page Experiment Verdict and Decision Proposal
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Code Review and Refactoring of a Legacy E-Commerce Module
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Design an Adaptive Home Screen for a Streaming Recommender
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Explore role
Strategy Analyst
Frame the business question, model the options, build the recommendation. From market sizing to competitive analysis, this role is where strategy consulting meets in-house decision-making.
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Build a Source-to-Source Migration Tool for a Legacy API
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Code-Smell Triage Workshop for a Hiring-Platform Backend
Run static analysis (SonarQube + a custom ruleset for domain-specific smells) on the four most-touched services. Score each smell on the 22-item Fowler catalog by occurrence cou…
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Rule on TaskFlow's Enterprise Landing Page A/B Test
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Open coursework Get recognized by recruiters and employers.
Credentials are blockchain-anchored via LearnCoin — tamper-evident, portable, link-shareable on LinkedIn and beyond.
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Cost-Quality Prompt Optimization at Scale
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Refactor a Tangled Java Pricing Engine With Design Patterns
Start from a provided Java 21 codebase with the legacy PricingEngine class, 38 example fixtures (input cart, expected price), and one failing test demonstrating a bug from last …
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Case File: Smart-Pointer Refactor of a Game-Engine Module
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Detect Use-After-Free with Pointer Analysis in a C++ Codebase
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Rate and Reduce Technical Debt in a Telecom OSS Codebase
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Capacity Planning Model for a Black-Friday Traffic Surge
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Add a Test Harness to an Untested Open-Source CLI
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Design a Domain Model for a Library Loan System (Java)
Implement, in Java 21, an Item type hierarchy (Book, AudioBook, Periodical, EquipmentLoan — each with sub-type-specific rules), Member with eligibility logic, Loan as an aggrega…
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Object-Oriented Programming and 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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