Browse by field of study
Computer & Information Sciences Challenges
Real-world challenges across Computer & Information Sciences. Pick the specific field you're studying, solve an actual brief, and walk away with verified, portable proof recruiters can confirm in one click.
Recommended challenges
- DesignSeniorNew
Design a Symbolic-Execution Test-Generation Pipeline for a Date-Time Library
Design a generation pipeline that turns the public parsing and arithmetic surface of the supplied library module into branch-covering test inputs using a symbolic-execution engi…
- Symbolic Execution
- Klee
- Test Generation
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…
- Pointer Analysis
- Static Analysis
- Use After Free
Open coursework - CodeIntermediateNew
Find the Dead Code Hiding in a Python Monorepo
Build a dataflow- and call-graph-based dead-code detector in Python (using libcst, or the standard ast module together with jedi) and prove it on the materials provided. Run it …
- Dataflow Analysis
- Ast
- Call Graph
Open coursework - DesignSeniorNew
Design a Semantic Configuration Validator Using Abstract Interpretation
Using the configuration schema reference, the three incident post-mortems, and the 200-configuration validation set provided, design an abstract domain that captures relations b…
- Abstract Interpretation
- Static Analysis
- Rust Programming
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.
Why Ewance
- CodeBeginnerNew
Refactor a Legacy Reporting Script for a Renewable-Energy Startup
Read the existing script and identify 5-7 distinct responsibilities tangled together. Refactor into 3 layers: data loaders (CSV, REST API), transformers (pure functions over row…
- Abstraction
- Higher Order Functions
- Refactoring
Programming Abstractions - CodeBeginnerNew
Build a Safe Expression Evaluator for a Math-Learning App
Working only from the materials provided, build a self-contained expression evaluator in Python (TypeScript is acceptable if you mirror the same structure) that never calls eval…
- Recursion
- Higher Order Functions
- Parsing
Open coursework - CodeBeginnerNew
Build a Functional Image-Filter Pipeline for a Photography SaaS
Design a Filter as a function from (pixel matrix → pixel matrix). Build a compose helper that takes a list of filters and returns a single composed filter (function composition)…
- Higher Order Functions
- Function Composition
- Abstraction
Open coursework - CodeIntermediateNew
Build a Shareable Immutable List for a Real-Time Document Editor
Using the provided API specification (persistent-list-spec) and the starter module (immutable-list-starter), implement a persistent immutable list supporting get, set, append, p…
- Data Abstraction
- Recursion
- Persistent Data Structures
Open coursework - 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.
- DesignIntermediateNew
Design an Invoice-Rules Mini-Language for Non-Technical Users
Design a rule mini-language whose grammar (written in Backus-Naur Form, the standard notation for describing grammars) covers boolean logic (and / or / not), comparison operator…
- Abstraction
- Recursion
- Domain Specific Language
Open coursework - CodeIntermediateNew
Multi-Tenant Schema Migration for a Series-B HR SaaS
Design a 4-phase migration: (1) add new columns + tables, dual-write on every workflow mutation, (2) backfill 3.4 TB in chunks of around 50k rows per minute with throttling and …
- Multi Tenant Architecture
- Schema Migration
- Dual Write
Open coursework - CodeIntermediateNew
Build a Metered-Billing System for a Usage-Based SaaS
Build an event-ingest API (Express + Redis Streams) that receives usage events with idempotency keys. Aggregate hourly into Postgres rollups using a windowed worker that survive…
- Metered Billing
- Idempotency
- Event Aggregation
Open coursework - DesignIntermediateNew
Authentication + RBAC for a Multi-Workspace SaaS
Design the auth architecture: identity provider (managed), session model (JWT with rotation), workspace-membership claims, RBAC permission model (4 default roles, custom-role ca…
- Authentication
- Rbac
- Sso
Engineering Software as a Service Get recognized by recruiters and employers.
Credentials are blockchain-anchored via LearnCoin — tamper-evident, portable, link-shareable on LinkedIn and beyond.
Why Ewance
- StrategyBeginnerNew
REST API Versioning Strategy for a 4-Year-Old Public API
Pick a versioning scheme (URI path vs header-based) and justify it against integrator behavior. Define the deprecation lifecycle: announce → deprecate → sunset, with concrete ti…
- REST API Design
- API Versioning
- Openapi
Engineering Software as a Service - CodeBeginnerNew
CI/CD Pipeline for a SaaS Monorepo with 14 Services
Set up Nx (or Turborepo) for affected-graph computation. Configure remote build cache (S3-backed) so cached steps skip across runs and developers. Parallelize jobs in GitHub Act…
- Ci Cd
- Monorepo
- Nx
Open coursework - DesignBeginnerNew
Design a Playwright Checkout Test Suite That Blocks Bad Merges
Using the checkout incident export, identify the single most valuable happy path plus the six edge cases tied to the most frequent and most severe past incidents (for example fa…
- End To End Testing
- Playwright
- Ci Cd
Open coursework - CodeIntermediateNew
Property-Based Testing to Harden a SEPA Payments Parser
Work only from the four supplied items: the de-identified incident log of the last four quarterly parser failures (incident-log), the representative parser module (parser-module…
- Property Based Testing
- Fuzz Testing
- Go
Open coursework - CodeIntermediateNew
Kill Surviving Mutants in a Travel Pricing Service
Work entirely from the provided pricing module (pricing-module) and its existing test suite (existing-tests), using the scenario facts in the briefing document (challenge-brief)…
- Mutation Testing
- Java
- Junit
Open coursework - StrategyBeginnerNew
Risk-Based Test Strategy for a Telehealth Scheduling Release
Using the module inventory case-file, the risk-scoring template, and the team-and-runway brief, design and document a risk-based test strategy for the seven-module scheduling re…
- Risk Based Testing
- Test Strategy
- Test Planning
Open coursework - StrategyIntermediateNew
Stand Up Contract Testing for a Logistics Microservices Backend
Using only the materials provided, choose and justify the six producer-consumer service pairs to migrate first. Read the 90-day staging breakage log to rank pairs by how much pa…
- Contract Testing
- Pact
- Microservices
Open coursework - CodeBeginnerNew
Build a Booking Web App for a Boutique Hotel Group
Design the data model (properties, rooms, availability, bookings, guests). Build the Next.js app with the App Router: 4 public pages (search, results, room detail, checkout), 1 …
- Nextjs
- React
- REST API
Web Application Development - 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
Open coursework - CodeBeginnerNew
REST API + Admin Dashboard for a Tutoring Marketplace
Map the 5 operator workflows by shadowing 2 operators for 4 hours (recordings provided). Design REST endpoints (Open API spec) covering each workflow with role-based scopes (ope…
- REST API
- Vuejs
- Rbac
Web Application Development - CodeBeginnerNew
Performance Optimization for a Slow Storefront
Run Lighthouse + WebPageTest baselines on 3 representative pages (home, product detail, cart). Set up Real User Monitoring (RUM) via Vercel Analytics or web-vitals.js. Ship 5 di…
- Web Performance
- Core Web Vitals
- Nextjs
Web Application Development - CodeIntermediateNew
Multi-Tenant SaaS Backend with Postgres Row Security
Design the multi-tenant schema: shared tables with a tenant_id column, indexed appropriately. Write a forward + backward migration (using Drizzle or Prisma). Implement Postgres …
- Multi Tenant Architecture
- Postgresql
- Row Level Security
Open coursework
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.