Computer Science
Programming Fundamentals Challenges
Programming Fundamentals challenges put you inside the work of writing code that is correct, readable and fast. You'll build core skills in functions & data structures, object-oriented design and design patterns, work in Python or JavaScript, and learn to do code reading and refactoring the way teams expect.
From there you'll tackle the harder edges — algorithm analysis, complexity analysis, graph algorithms and generics & type systems — pushing into performance engineering, low-latency programming patterns and systems-language proficiency (Go, Rust, C++). Each challenge you solve earns a verified credential you can share with recruiters.
- CodeBeginnerNew
Responsive Web Redesign for SaaS Scale-up
You are to redesign the TaskFlow website's homepage, pricing page, and a new 'Enterprise' landing page. The redesign must be responsive (mobile-first) and built with HTML/CSS/JS…
- Html
- Css
- Javascript
Open coursework - CodeIntermediateNew
Forecast Intraday FX Volatility for a London Liquidity Desk
You receive 18 months of tick-level mid-quote data for six FX pairs plus a calendar of scheduled macro events. Resample to 1-minute bars, engineer realized-volatility features, …
- Time Series Forecasting
- Feature Engineering
- Model Validation
Open coursework - CodeBeginnerNew
Churn-Prediction Model for a B2B Vertical SaaS
Use 18 months of anonymized data (provided) covering: usage events, login frequency, support tickets, NPS responses, billing health, feature adoption, practice firmographics. De…
- Supervised Learning
- Python Programming
- Ml Applications
Machine Learning (CS Elective) - AnalysisBeginnerNew
Stress-Test a Hiring-Funnel Model for Bias
You receive a synthetic-but-realistic dataset of 25,000 past applicants with features (years of experience, education tier, prior role tags) and outcome labels (advanced past th…
- Model Evaluation
- Fairness Metrics
- Logistic Regression
Machine Learning (Undergraduate) 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
Build a Crawler-and-Topic Pipeline for Public-Sector Web Analytics
You will build a polite, robots.txt-respecting crawler that ingests about 30,000 new posts/week across the 80 forums into a normalized dataset. Apply a topic model (BERTopic, wi…
- Web Crawling
- Topic Modeling
- NLP Pipeline
Open coursework - CodeBeginnerNew
Tune a Recommender for an EU Streaming Music App
Use the public Last.fm-360k or similar dataset (anonymized listening histories) as a stand-in. Implement a baseline matrix-factorization recommender, then a hybrid that adds tra…
- Recommender Systems
- Feature Engineering
- Model Evaluation
Open coursework - CodeIntermediateNew
LLM-Powered FAQ Chatbot for 40-Person SaaS Scale-up
You have access to TaskFlow's internal documentation, help articles, and a sample of 500 support tickets. Your task is to build a retrieval-augmented generation (RAG) pipeline: …
- LLM
- RAG
- Information Retrieval
Text Analytics and Natural Language Processing - AnalysisBeginnerNew
Build a Public Open-Data Dashboard for Urban Mobility
Pull the city's open-data cyclist-collision dataset (10 years of incidents, geocoded). Define a clear before/after window around the protected-lane rollout, control for traffic-…
- Exploratory Data Analysis
- Data Wrangling
- Geospatial Analysis
Applied Data Analysis and Practical Data Science - Browse challenges
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Pricing Strategist
Set the price that captures value without leaving sales on the table. Demand modelling, willingness-to-pay research, and the disciplined experimentation that turns pricing into a competitive advantage.
- DesignBeginnerNew
Detect Sensor Drift for a Field Inspection Robot Fleet
You receive 60 days of telemetry from 12 robots, including IMU readings, camera exposure stats, and the inspection-quality scores produced downstream. Define drift signals (roll…
- Anomaly Detection
- Change Point Detection
- Sensor Fusion
Open coursework - AnalysisBeginnerNew
Map Creator Communities for a Short-Form Video Platform
You receive a 90-day sample of about 4 million creator-creator interactions (duets, mentions, audience overlap) and creator metadata (region, language, content tag). Build a cre…
- Network Analysis
- Community Detection
- Graph Visualization
Open coursework - CodeSeniorNew
Bulk Synchronous Parallel PageRank for a Web-Graph Lab
Working from the lab situation record (`lab-case-file`), implement 25 iterations of PageRank under a Bulk Synchronous Parallel (BSP) model using either Apache Spark with GraphX …
- Parallel Algorithms
- Bsp
- Graph Algorithms
Open coursework - CodeIntermediateNew
Index a Reference Genome with a Suffix Array in Rust
Using the reference-genome FASTA in the provided materials, build an in-memory suffix array (DC3 or SA-IS construction) over the 4-letter DNA alphabet in Rust, then implement co…
- Suffix Arrays
- String Algorithms
- Rust
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
- CodeIntermediateNew
Forecast Energy Demand for a Nordic Renewable Utility
You receive 5 years of hourly residential-segment demand, hourly weather data (temperature, wind, irradiance), and a calendar of public holidays. Build a probabilistic forecaste…
- Time Series Forecasting
- Probabilistic Modeling
- Feature Engineering
Applied Machine Learning - CodeBeginnerNew
Design and Implement a C++ Telemetry Aggregator With Inheritance
Implement a TelemetrySource abstract base class with virtual sample() and timestamp() methods, 6 concrete subclasses (one per sensor family), and a TelemetryBus that polymorphic…
- Cpp
- Inheritance
- Polymorphism
Object-Oriented Programming and Design - CodeFoundationalNew
Tune a Pick-and-Place Controller for a Cosmetics Co-Packer
You receive 4 hours of logged trajectories from the existing controller (joint positions, target poses, miss/success labels) and read/write access to the controller config (YAML…
- Motion Control
- Trajectory Tuning
- Robot Kinematics
Open coursework - CodeIntermediateNew
Solve a Vehicle-Routing Problem with Tabu Search
You receive a week of anonymized daily VRPTW instances (around 800 orders per day, 120 vehicles, hard delivery windows). Implement tabu search with: a route-insertion constructi…
- Tabu Search
- Metaheuristics
- Vehicle Routing
Evolutionary Computation and Metaheuristic Search - CodeIntermediateNew
Design an SAT-Based Verifier for an Autonomous-Vehicle Test Lab
Model a simplified four-way intersection: agent positions, lights, and discrete time steps. Define 5 safety properties in propositional logic (e.g., 'no two agents in the inters…
- Sat Solving
- Logical Inference
- Formal Verification
Artificial Intelligence: Principles and Techniques - AnalysisBeginnerNew
Build a Topic-Modeling Pipeline for Citizen Feedback
Take the 60,000 comments (anonymized). Build a BERTopic pipeline with multilingual sentence embeddings (Catalan + Spanish + occasional English). Tune number-of-topics via topic-…
- Topic Modeling
- Bertopic
- Multilingual NLP
Open coursework - CodeSeniorNew
Physically-Based Path Tracer for a Product Visualization Studio
Build a path tracer in C++ with: ray-triangle and ray-sphere intersection on a BVH (bounding volume hierarchy), Lambertian diffuse and Cook-Torrance GGX specular BRDFs, multiple…
- Physically Based Rendering
- Path Tracing
- Shading And Lighting
Advanced Computer Graphics - CodeIntermediateNew
Add Idempotency Keys to a Payment Webhook System
Read the current Go webhook-sender code and 30 days of duplicate-delivery incident logs. Design the idempotency scheme: server-generated key per event (UUID v7 — time-ordered), …
- API Design
- Idempotency
- Webhooks
Open coursework - DesignIntermediateNew
Visualize Embedding Drift for a RAG Knowledge Assistant
You receive weekly snapshots over 12 weeks of around 50,000 document embeddings each (1024-dim). Design and build a visualization tool that: (a) projects each snapshot to 2D wit…
- Embeddings
- Dimensionality Reduction
- Umap
Open coursework - CodeSeniorNew
Build and Evaluate an LSM-Tree Storage Engine in Rust
Your analysis task is to complete the engine and produce an evidence-backed comparison of the two compaction strategies. Start from the 'starter-engine' Rust module and finish t…
- Lsm Tree
- Storage Engine
- Rust
Open coursework - CodeBeginnerNew
Hybrid Search RAG for a HR-Policy Assistant
You receive 1,800 pages of policy documents (Markdown) and 150 labeled question-answer pairs with the gold source policy IDs. Build a hybrid retrieval pipeline: BM25 + dense emb…
- Hybrid Search
- Bm25
- Dense Retrieval
Open coursework - CodeBeginnerNew
Demand Sensing for a 40-Person SaaS Scale-Up
You are a growth analyst at FlowMetrics. Using weekly data on signups, trial conversions, website traffic, and marketing spend, develop a model to forecast monthly subscription …
- Time Series Forecasting
- Regression Analysis
- Python
Forecasting for Decision Making
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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