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.
Recommended Challenges
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Build a Source-to-Source Migration Tool for a Legacy API
Use Python's libcst (concrete syntax tree library) to parse customer code while preserving formatting. For each of the 14 transformations, write a CST visitor that matches the v…
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Mine Basket History to Justify Grocery Shelf-Adjacency Changes
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Build and Ship a Bug-Tracker MVP with Full CI/CD
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Software Engineering Foundations 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.
Why Ewance
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Build a Hybrid Recommender for a Niche Consumer-AI Music App
You receive listening events (around 240 million plays) plus a content embedding per track (audio + curator tags). Build a collaborative filtering model (ALS or implicit-feedbac…
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Build a Canary Rollout for a Production Recommender
Pick a serving stack (Triton, Seldon Core, KServe, or BentoML). Implement two-model traffic splitting with a configurable percentage (start at 5%). Wire up online metric collect…
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Design a Semantic Configuration Validator Using Abstract Interpretation
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Nudge Strategy for a Bangalore D2C Cosmetics Brand
You are a behavioral economics consultant hired by Glow Naturals. Analyze their current checkout process (provided in a mockup) and identify cognitive biases causing friction. P…
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Behavioral Economics - Browse challenges
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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Rule on TaskFlow's Enterprise Landing Page A/B Test
Working only from the test results dataset and the test-setup brief in the provided materials, determine whether the redesigned page genuinely improves the demo-booking conversi…
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Design an Adaptive Home Screen for a Streaming Recommender
Using the recommender output specification and the session-signals fixture, design three adaptive layout variants that are each triggered by a viewing-intent signal derived from…
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Debug a Race Condition in a Real-Time Collaboration Service
Build a deterministic load-test harness (k6 or Playwright) that reproduces the corruption within 3 attempts on a clean local stack. Capture traces with OpenTelemetry to localize…
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Design a Lexer and Parser for a Customer Query Language
Using the grammar sketch, the query corpus sample, the Abstract Syntax Tree schema, and the edge-case suite provided to you, write a design proposal for a new lexer and parser t…
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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.
Why Ewance
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Code Review and Refactoring of a Legacy E-Commerce Module
You are given a codebase (Java/Spring Boot) of the order module. Perform a static analysis, document issues (e.g., god classes, tight coupling), and write a refactoring proposal…
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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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Design and Implement a C++ Telemetry Aggregator With Inheritance
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Design a Domain Model for a Library Loan System (Java)
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Build a Hybrid Recommendation System for an Indie Streaming Catalog
Use the provided 6-month anonymized event log (around 320M play events, 1.4M unique users in the held-out cohort), audio embeddings (256-d), and track metadata. Implement (1) an…
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Capacity Planning Model for a Black-Friday Traffic Surge
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Measure HTTP/3 vs HTTP/2 Video Delivery Over Cellular
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Open coursework - CodeSeniorNew
Detect Use-After-Free with Pointer Analysis in a C++ Codebase
Build the codebase with compilation database (compile_commands.json). Write a custom Clang static-analyzer checker (or extend an existing one) that flags resource-handle uses af…
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Program Analysis
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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