Computer Sciences Challenges
Explore computer science challenges on Ewance to equip yourself with job-relevant skills for a variety of roles. Learn programming techniques and build technical skills with challenges on software development, algorithm design, system architecture, and more.
Most Popular
- CodeIntermediateNew
Build a CodeQL Query Pack to Catch Logging-of-PII
Use CodeQL to write queries for Java and Python that detect data flow from PII sources (request parameters, database columns marked PII, user-profile fields) into logging sinks …
- Static Analysis
- Codeql
- Data Flow Analysis
Program Analysis - CodeIntermediateNew
Bloom Filter Cache to Cut Origin Load at a CDN Edge
Given a target false-positive rate of 1 percent at 200 million keys per shard, compute the optimal bit-array size (m) and hash-function count (k) using the canonical formulas. I…
- Bloom Filters
- Probabilistic Data Structures
- Hash Functions
Randomized Algorithms - AnalysisIntermediateNew
Randomized Load Balancer with the Power of Two Choices
Simulate four placement policies on a 24-hour anonymized connection-establishment trace (around 4.1 billion events): (1) random-1, (2) round-robin, (3) P2C with instantaneous lo…
- Power Of Two Choices
- Load Balancing
- Randomized Algorithms
Randomized Algorithms - CodeIntermediateNew
Reservoir Sampling for a Privacy-Preserving Telemetry Pipeline
Implement Vitter's Algorithm R (and the faster Algorithm L for bonus credit) producing a 90M-event uniform sample per day from a stream of 18B. Add per-key stratification (so lo…
- Reservoir Sampling
- Randomized Algorithms
- Streaming Systems
Randomized Algorithms 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.
Why Ewance
- CodeIntermediateNew
Apply the Mikado Method to Untangle a Tax-Engine Class
Starting from the live codebase (Java 17, 73 percent line coverage), write a failing test that asserts the desired end state ('TaxCalculator is decomposed into per-country strat…
- Mikado Method
- Refactoring
- Strategy Pattern
Refactoring and Code Smell Detection - CodeIntermediateNew
Strangler-Fig Migration of a Monolithic Order Service
Stand up an HTTP facade in front of the monolith (Nginx or a small Go proxy) that routes by URL pattern. Slice 1: extract the order-status read endpoint, dual-write nothing, rou…
- Strangler Fig Pattern
- Refactoring
- Legacy Modernization
Refactoring and Code Smell Detection - CodeIntermediateNew
FFT-Based Acoustic Beamforming on Streaming Microphone Arrays
Implement overlap-add streaming FFT (FFTW or KissFFT) processing 64 channels × 1024-sample frames with 50 percent overlap. Apply delay-and-sum beamforming across a 2D direction-…
- Fft
- Signal Processing
- Beamforming
Scientific Computing and Numerical Methods - AnalysisIntermediateNew
Empirical Study of PR Review Throughput on a Mid-Sized Monorepo
Pull 8 weeks of PR data from the monorepo (~3,800 PRs across 12 teams) covering open-to-merge time, review-comment count, review-round count, reviewer count, lines changed, and …
- Empirical Software Engineering
- Software Analytics
- Statistical Analysis
Advanced Software Engineering - Browse challenges
Explore role
Marketing Analyst
Plan and measure campaigns that grow the business. Funnel analytics, attribution, segmentation, and the rigorous measurement that lets marketing defend its budget at the leadership table.
- CodeIntermediateNew
Software Analytics Dashboard for an Engineering Org
Author a metric catalog defining each of ~15 metrics with formula, data source, refresh cadence, and known caveats (e.g. lead-time-for-changes excludes WIP-flagged PRs to avoid …
- Software Analytics
- Dora Metrics
- Space Framework
Advanced Software Engineering - ResearchIntermediateNew
Industrial Case Study: Why a Microservices Migration Failed
Conduct 8 1-hour interviews across CTO, 3 tech leads, 2 platform engineers, 1 SRE, and the product VP. Analyze 24 months of artifacts (ADRs, RFCs, incident reports, deployment d…
- Industrial Case Study
- Qualitative Research
- Software Architecture
Advanced Software Engineering - AnalysisIntermediateNew
Reverse-Engineer a 22-Year-Old COBOL Batch Pipeline
Use SonarQube + cobol-language tooling + JCL parsers to extract job dependencies and data-flow across the 140 jobs. Build a job-dependency graph (Graphviz). Run impact analysis:…
- Reverse Engineering
- Legacy Systems
- Dependency Analysis
Software Evolution and Maintenance - CodeIntermediateNew
Refactor a Big-Ball-of-Mud Java Servlet Application
Week 1: install JUnit 5 + Testcontainers harness, write characterization tests for the 2 target workflows (PolicyIssue + ClaimSubmit) reaching at least 80 percent branch coverag…
- Refactoring
- Characterization Testing
- Legacy Systems
Software Evolution and Maintenance Build a verifiable portfolio.
Submissions become evidence. Reviewers with shipping experience score against a rubric; the result becomes a credential anyone can verify.
Why Ewance
- CodeIntermediateNew
Strangler-Fig Modernization of a Healthcare Reporting Service
Audit the report categories (around 14) and pick operating-theater utilization for the pilot extraction (high volume, moderate complexity, low regulatory blast-radius). Design t…
- Strangler Fig
- Legacy Systems
- Feature Flags
Software Evolution and Maintenance - DesignIntermediateNew
Build a Quality Metrics Program for a Medical-Device Software Team
Read the team's QMS (Quality Management System) documents and the IEC 62304 software lifecycle requirements. Design a metric catalog of 12-15 metrics covering process (review-co…
- Quality Metrics
- Iec 62304
- Process Improvement
Software Quality and Process Improvement - CodeIntermediateNew
Secure the Software Supply Chain of an Open-Source SDK
Audit the current state: dependency tree, publish process, GitHub Actions workflows, signing posture. Generate an SBOM (CycloneDX format) using Syft. Run OpenSSF Scorecard and t…
- Supply Chain Security
- Slsa
- Sbom
Software Security - AnalysisIntermediateNew
Secure-by-Design Review of a Microservices Auth Subsystem
Read the 18-page proposed auth-service design (Next.js BFF, FastAPI auth-service, Postgres for sessions + refresh, Redis for short-lived tokens, integration with Auth0 for OIDC)…
- Secure Design
- OWASP Asvs
- Oauth2
Software Security - CodeIntermediateNew
Property-Based Testing for a SEPA Payments Library
Read the SEPA Pain.001 XSD (XML Schema Definition) and pick 5 invariants the parser MUST preserve (e.g., 'sum of transactions equals control sum', 'IBAN passes mod-97 check', 'c…
- Property Based Testing
- Fuzz Testing
- Systems Language Proficiency (Go, Rust, C++)
Software Testing and Quality Assurance - CodeIntermediateNew
Real-Time Collaboration Whiteboard with WebSockets
Design the board state model (sticky notes + cursor positions) and pick a conflict-resolution approach (last-write-wins for v1, or operational-transform if scoping allows). Buil…
- Websockets
- React
- Nodejs
Web Application Development - CodeIntermediateNew
Implement Model Predictive Control for a Delivery Robot
You receive a kinematic bicycle model of the robot, a published track layout, and 30 minutes of recorded waypoint trajectories. Implement a nonlinear MPC controller using acados…
- Model Predictive Control
- Optimal Control
- Robotics Simulation
Advanced Robotics - StrategyIntermediateNew
Design a Compliance Strategy for an AI Robo-Advisor in the EU
Anchor the work on the published EU AI Regulation risk classification (limited vs. high-risk systems) and the European Securities and Markets Authority guidelines on robo-advice…
- Ai Governance Frameworks
- Regulatory Analysis
- Product Strategy
AI and Quantitative Finance - DesignIntermediateNew
Design a Lab-Automation Pipeline for a Bangalore Materials Startup
Design (not build) the full closed-loop lab pipeline: data layer (LIMS plus experiment store), model layer (a surrogate plus an acquisition function such as Expected Improvement…
- Systems Architecture
- Active Learning
- Mlops Design
AI for Science and Engineering - DesignIntermediateNew
Train a Self-Play Agent for a Card-Game Edtech Demo
Implement a small two-player imperfect-information card game (Kuhn poker or a 3-card simplified Hold'em variant). Implement CFR or CFR+ for the game and run self-play for at lea…
- Counterfactual Regret Minimization
- Self Play
- Game Theory
Artificial Intelligence: Principles and Techniques - AnalysisIntermediateNew
Draft GDPR + AI Act Data Provisions for a Training-Data Vendor
Anchor the work on (1) GDPR Articles 28 (processor obligations) and 32 (security), (2) the EU AI Regulation's data-governance article for high-risk systems, and (3) the EDPB's p…
- Data Protection Law
- Contract Redlining
- Regulatory Analysis
AI Law, Policy, and Regulation - CodeIntermediateNew
Ship an MVP RAG Knowledge Assistant for a Climate-Tech Startup
As a 4-person team across a 6-week sprint, ship: (1) an ingestion pipeline for around 4,000 mixed PDFs and markdown files; (2) a vector store with documented chunking strategy; …
- RAG Architectures
- Software Engineering For Ai
- Vector Databases
AI Software Engineering Group Project
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.



















































































