Python Or JavaScript
If you like applying Python Or JavaScript, every challenge here gives you a chance to practice it on a real industry brief.
- AnalysisIntermediateNew
Interpretable-by-Design GAM for an Insurer's Claims Triage
You receive an anonymized claims dataset (around 60,000 claims, target: log reserve), a feature schema (22 features), and an existing LightGBM baseline (held-out R^2 of 0.78). T…
- Generalized Additive Models
- Ebm
- Interpretability
Explainable and Interpretable AI - AnalysisIntermediateNew
Spectral-Analyze Wearable Sleep Data for a Healthtech Pilot
You receive 30 nights of wearable data per 25 volunteers, with polysomnography-derived ground-truth stages (Wake / NREM / REM). Engineer spectral features (delta, theta, alpha, …
- Spectral Analysis
- Feature Engineering
- Wavelet Analysis
Time Series Analysis and Forecasting - CodeIntermediateNew
Implement Async Message-Passing for an IoT Gateway
Receive the current gateway source (Python 3.11, single-threaded paho-mqtt client + a serial HTTP forwarder, ~1,100 lines), a sensor-simulator that fans out 500 mock sensors at …
- Async Programming
- Message Passing
- Asyncio
Concurrent and Parallel Programming - CodeIntermediateNew
Structured-Output Prompts for Invoice Extraction
You receive 300 real invoice transcripts (already OCR-ed) labeled with 14 target fields, plus the current production prompt and its 12 percent failure log. Design a new prompt u…
- Structured Output
- Json Schema
- Few Shot Prompting
Prompt Engineering Practice your coursework on real scenarios.
Every challenge is shaped from real industry context — not generic exercises. The work mirrors what your degree prepares you for.
Why Ewance
- CodeIntermediateNew
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
Applied Machine Learning - CodeIntermediateNew
Implement a Distance-Vector Routing Algorithm
Implement distance-vector routing in Python: each simulated router maintains a distance vector, exchanges vectors with neighbors every 1 second of simulated time, and updates it…
- Routing
- Distance Vector
- Network Simulation
Computer Networks - CodeIntermediateNew
Compare MDP Solvers for a Smart-Grid Battery Dispatch Pilot
Model home-battery dispatch as a finite MDP: state is (state-of-charge, hour-of-day, current price tier), actions are charge/hold/discharge with realistic efficiency losses, tra…
- Markov Decision Processes
- Value Iteration
- Policy Iteration
Artificial Intelligence: Principles and Techniques - CodeIntermediateNew
Forecast Hourly Energy Demand for a Microgrid Operator
You receive 24 months of hourly demand, weather (temperature, irradiance), and calendar data for the community. Build a probabilistic forecaster (e.g., quantile regression with …
- Probabilistic Forecasting
- Quantile Regression
- Deep Forecasting
Time Series Analysis and Forecasting - 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.
- AnalysisIntermediateNew
Refit a Pricing Model for an Insurance Comparison Site
You receive 9 months of quote-impression data (about 14 million events) with about 60 features and click labels. Refit logistic regression with elastic-net regularization plus a…
- Regularized Regression
- Feature Interactions
- Calibration
Statistical Machine Learning - AnalysisIntermediateNew
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
Natural Language Processing - CodeIntermediateNew
Containerize a Legacy Java Monolith and Deploy to ECS
Receive the Java 8 monolith source (around 320k lines), the current Tomcat + Apache HTTPD config, and 30 days of production traffic logs. Containerize the application (multi-sta…
- Containerization
- Docker
- AWS Or Azure
Cloud Computing - CodeIntermediateNew
Build Semantic Search for an Internal Engineering Wiki
You receive a Confluence XML export (~12k pages, ~80 MB of text) and a hand-labeled benchmark of 50 internal queries with ground-truth doc IDs. Chunk and embed the corpus with a…
- Embedding Models
- Vector Database Basics
- Pgvector
Vector Databases and Embeddings 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
- ResearchIntermediateNew
Hyperparameter Search via CMA-ES for a Pharma QSAR Model
You receive a labeled QSAR dataset (around 25,000 compounds, regression on a binding-affinity target), a fixed feature pipeline (Morgan fingerprints + descriptors), and the team…
- Cma Es
- Metaheuristics
- Hyperparameter Optimization
Evolutionary Computation and Metaheuristic Search - CodeIntermediateNew
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
Social Network Analysis and Web Science - AnalysisIntermediateNew
Diagnose Churn Drivers for a B2B SaaS Workflow Tool
You receive three CSV exports: 18 months of weekly product-usage events for about 1,800 accounts, the full support-ticket history, and account firmographics (industry, size, pla…
- Exploratory Data Analysis
- Data Wrangling
- Feature Engineering
Applied Data Analysis and Practical Data Science - AnalysisIntermediateNew
Detect Fraudulent Refund Requests for a Mid-Market Marketplace
You receive a labeled dataset with buyer history, seller history, shipping carrier, refund reason text, and outcome label (legit / fraud). Train and evaluate at least two classi…
- Classification
- Model Calibration
- Imbalanced Classification
Machine Learning (Undergraduate) - CodeIntermediateNew
Intelligent Agent for a Smart-Thermostat Pricing-Aware Schedule
Design an intelligent agent with: perception (read sensor history), basic learning (cluster comfort intervals from 7 days of observations), decision-making (schedule heating to …
- Intelligent Agents
- Basic Learning
- Python Or JavaScript
Introduction to Artificial Intelligence (CS Elective) - CodeIntermediateNew
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
- HTML & CSS
- Python Or JavaScript
Web and Mobile Application Development - AnalysisIntermediateNew
Optimizing Last-Mile Delivery for a San Francisco Grocery Startup
Your task is to formulate a minimum-cost flow problem for daily delivery routes. Use the provided order data (locations, time windows, volumes) and vehicle specs (capacity, spee…
- Linear Programming
- Network Flow
- Python Or JavaScript
Operations Research and Optimization - ResearchIntermediateNew
Evaluate Speech Synthesis Voices for an EdTech Storyteller App
You will generate 60 audio clips (20 per vendor) covering 4 story genres and 3 emotional tones. Recruit 15 native Spanish speakers via a remote panel (Prolific or local equivale…
- Tts Evaluation
- Listening Studies
- Mos Scoring
Speech Recognition and Spoken Language Processing - CodeIntermediateNew
Implement an Expression Evaluator Using Recursion and Higher-Order Functions
Implement in Python (or TypeScript). Build a tokenizer, a recursive-descent parser producing an abstract syntax tree (AST), and a tree-walking evaluator. Use higher-order functi…
- Recursion
- Higher Order Functions
- Parsing
Programming Abstractions - AnalysisIntermediateNew
Customer-Segmentation Study for a DTC Subscription Box
Use 18 months of anonymized data: order history, churn events, NPS responses, box-rating data, referral activity, marketing-channel attribution. Engineer features (RFM-style + b…
- Unsupervised Learning
- Python Or JavaScript
- Ml Applications
Machine Learning (CS Elective) - CodeIntermediateNew
Shortest-Path Routing for a Bike-Share Operator
Receive the graph (nodes with lat/lon/elevation, edges with length and slope) and 50 origin-destination test pairs. Implement Dijkstra's algorithm with a custom edge-weight func…
- Graph Algorithms
- Dijkstra
- Algorithm Analysis
Algorithm Design and Analysis - CodeIntermediateNew
Apply SOLID to a Java Reporting Service for a Renewable Energy Startup
Receive the legacy ReportService, 4 sample report templates (Daily Output, Monthly P&L, Annual Availability, Curtailment), and 22 fixtures (input dataset, expected report). Refa…
- Python Or JavaScript
- Solid Principles
- Refactoring
Object-Oriented Programming and Design
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
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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.



















































































