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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Migrate a 600K-LOC Monolith to a Modular Monolith
Run static dependency analysis on the monolith (using Packwerk + custom Ruby AST scripts, both available) to surface the current implicit modules and the worst cross-module depe…
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Advanced Software Engineering - CodeIntermediateNew
Stand Up Contract Testing for a Microservices Backend
Inventory the 18 services and pick the 6 producer-consumer pairs with the most staging breakages in the last 90 days. Stand up a Pact broker (self-hosted or PactFlow trial). For…
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Software Testing and Quality Assurance - AnalysisIntermediateNew
A/B Testing for a 40-Person SaaS Scale-up Moving to Enterprise
You are a data analyst at TaskFlow. You are given the raw A/B test data (visitor logs, conversions, and downstream sales data). Your task is to perform a rigorous analysis: chec…
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Data Science for Business - CodeIntermediateNew
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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ML Engineering and Production ML 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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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…
- Code Smells
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Refactoring and Code Smell Detection - AnalysisBeginnerNew
Run an A/B Test on Two System Prompts for a Sales Email Assistant
You will (1) design the A/B test (random assignment by rep_id, 50/50 split, 2-week duration), (2) instrument three primary metrics: reply rate (event-based), average tokens per …
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LLM Application Development - CodeIntermediateNew
Containerized Model Inference on Kubernetes for a Fintech
You receive a pre-trained credit-risk model (a LightGBM model file) and a sample request payload. Containerize a FastAPI inference service, deploy to EKS or GKE (a single-zone c…
- Kubernetes Orchestration
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Cloud Computing for Data and ML - CodeSeniorNew
Abstract-Interpretation-Based Configuration Validator for a SaaS Platform
Define an abstract domain capturing relations between configuration fields (e.g. 'if billing.plan = enterprise then features.audit_log = true'). Implement an abstract-interpreta…
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Program Analysis - Browse challenges
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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.
- CodeBeginnerNew
Build and Ship a Bug-Tracker MVP with Full CI/CD
Week 1: write a 1-page SRS + Figma wireframes for 5 screens (login, bug list, bug detail, file bug, dashboard). Week 2-3: implement with Next.js + Supabase + Tailwind, with unit…
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Software Engineering Foundations - CodeBeginnerNew
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…
- Python Or Javascript
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Object-Oriented Programming and Design - CodeIntermediateNew
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…
- Debugging
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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 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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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…
- Abstract Syntax Trees
- Source To Source Transformation
- Python Or Javascript
Compiler Construction - CodeBeginnerNew
Build a Secure-Coding Linter Ruleset for a Backend Team
Receive the last 12 security-review findings, 3 representative repos (Node.js + TypeScript), and access to a CI pipeline (GitHub Actions). Build a custom Semgrep ruleset (or ESL…
- Secure Coding
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Introduction to Computer Security - CodeBeginnerNew
Build a Plugin-Based Notification Framework With Observer + Factory
Implement, in Java 21: an EventBus that supports typed subscriptions, a NotificationChannel interface with concrete subtypes (Push, Email, InApp, SMS), an AbstractChannelFactory…
- Python Or Javascript
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Object-Oriented Programming and Design - CodeBeginnerNew
Build an End-to-End Test Suite for a Checkout Flow
Inventory the last 6 months of production checkout incidents (anonymized export provided). Pick the top 7 user journeys (1 happy path + 6 highest-incident edge cases) and write …
- End To End Testing
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Software Testing and Quality Assurance - AnalysisFoundationalNew
Optimize Ad Spend for Munich D2C Cosmetics Brand
You are given a CSV dataset with 10,000 rows of ad performance data including date, campaign, audience segment, creative type, impressions, clicks, conversions, and spend. Your …
- A/B Testing
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Marketing Analytics - AnalysisIntermediateNew
Capacity Planning Model for a Black-Friday Traffic Surge
Pull 18 months of per-service request rate + utilization from Prometheus. Forecast BFCM traffic per service using a baseline + multiplicative seasonal model (Prophet or statsmod…
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Site Reliability Engineering - 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…
- Pointer Analysis
- Static Analysis
- Use After Free
Program Analysis - CodeIntermediateNew
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…
- Code Review
- Refactoring
- Python Or Javascript
Software Engineering and Quality Assurance
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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