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.
- CodeIntermediateNew
Repository + Unit-of-Work Refactor on an EF Core Codebase
Read the data-access patterns across the 5 bounded contexts (Payroll, Timesheets, Benefits, Org, Reporting) and tag the 12 worst N+1 incidents from the last quarter's traces. Au…
- Repository Pattern
- Unit Of Work
- Design Patterns
Software Design and Design Patterns - CodeIntermediateNew
Edge-Inference Pipeline for a Smart-Factory Vibration Monitor
Architect a pipeline that runs on an ESP32-S3 + STM32 combo (provided): (1) sample 3-axis accelerometer at 3.2 kHz, (2) compute windowed FFT features on-device every 1s, (3) run…
- Edge Computing
- Embedded Systems
- Sensors And Actuators
Internet of Things and Cyber-Physical Systems - CodeIntermediateNew
Build a Streaming Pipeline for Real-Time Fraud Detection
Receive 30 days of anonymized card-transaction events (around 240M events total), the team's existing batch features (cardholder behavior summaries), and a pre-trained fraud-sco…
- Stream Processing
- Kafka Event Streaming
- Flink
Big Data and Data-Intensive Systems - 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 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
- AnalysisBeginnerNew
Mine Association Rules for a Grocery Retailer's Promo Strategy
You receive 6 months of basket-level transaction data (around 22 million baskets, around 18,000 SKUs) plus a category taxonomy. Run association-rule mining (Apriori or FP-Growth…
- Association Rules
- Market Basket Analysis
- Apriori
Data Mining and Knowledge Discovery - CodeIntermediateNew
Natural Language Inference for an HR-AI Compliance Tool
Use SNLI/MNLI/ANLI as starting data and curate 200 domain-specific HR examples (synthetic or anonymized) for fine-tuning. Fine-tune a small encoder (DeBERTa-v3-base or similar),…
- Natural Language Inference
- Transformer Models
- Fine Tuning
Computational Semantics - CodeBeginnerNew
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 - CodeBeginnerNew
Build a Bounded Concurrent Queue for a Microservice Worker Pool
Implement a bounded concurrent queue in Go (no third-party queue libraries; standard library + sync primitives only) that supports: Put(item) blocks when full, TryPut(item, time…
- Concurrent Data Structures
- Mutex And Condvar
- Systems Language Proficiency (Go, Rust, C++)
Concurrent and Parallel Programming - 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.
- 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 Or Javascript
- Ml Applications
Machine Learning (CS Elective) - ResearchIntermediateNew
Design a Capability Evaluation for an Open-Weights Coding Model
Pick a recent open-weights coding model (e.g., a Qwen, DeepSeek, or Llama variant). Design an evaluation set of around 40 coding tasks across 4 buckets: standard benign coding, …
- Capability Evaluation
- Safety Evaluation
- LLM Evaluation
AI Safety and Alignment - PresentationIntermediateNew
Design a Hybrid Symbolic-Neural Agent for an Enterprise RAG Demo
Design a hybrid agent for a 'company-policy assistant' demo: a symbolic planner decomposes user goals into typed subtasks ('find policy', 'check applicability', 'compose answer'…
- Hybrid Ai
- Symbolic Planning
- RAG Architectures
Artificial Intelligence: Principles and Techniques - CodeIntermediateNew
Diagnose Equipment Failures with a Bayesian Network
You receive 90 days of sensor logs (vibration, spindle temperature, coolant flow, ambient humidity), the maintenance log of 180 failure events labeled by root cause, and a short…
- Bayesian Networks
- Probabilistic Inference
- Parameter Learning
Probabilistic Graphical Models Get recognized by recruiters and employers.
Credentials are blockchain-anchored via LearnCoin — tamper-evident, portable, link-shareable on LinkedIn and beyond.
Why Ewance
- CodeIntermediateNew
Build an Indexer for an On-Chain DeFi Analytics Product
Receive the 6 protocols' ABIs + the team's required event coverage spec (around 40 event types). Build a TypeScript indexer using viem + Postgres: subscribe to new blocks via We…
- Blockchain Indexing
- Typescript
- Ethereum
Blockchain and Decentralized Systems Engineering - AnalysisIntermediateNew
Evaluate OS-Level Containment for a Multi-Tenant Edge Platform
Set up reproducible environments for gVisor, Firecracker, and Wasmtime on identical hardware (4 vCPU, 8 GB RAM). Run the platform's 4 workload archetypes (anonymized): API proxy…
- Containment
- Virtualization
- Wasm
Advanced Operating Systems - CodeIntermediateNew
MinHash Similarity Sketch for a Job-Board Deduplication Pipeline
Implement a MinHash signature generator (128 permutations) over shingled job-posting text (5-gram word shingles). Build an LSH banding index (16 bands of 8 hashes each) tuned fo…
- Minhash
- Locality Sensitive Hashing
- Probabilistic Data Structures
Randomized Algorithms - CodeSeniorNew
Build a Secure Multi-Party Computation Demo for Cross-Bank Fraud Detection
Pick MP-SPDZ as the MPC framework. Build a 4-party demo computing two protocols: (1) private set intersection of suspicious-account IDs across banks, (2) joint aggregate (count …
- Secure Computation
- Mpc
- Cryptography
Privacy-Enhancing Technologies - CodeIntermediateNew
Index a Genomics Dataset with a Suffix Array for Read Matching
Implement a suffix array over a 720 MB DNA sequence (4-character alphabet) using DC3 (Difference Cover modulo 3) or SA-IS construction in Rust. Build pattern-matching utilities …
- Suffix Arrays
- String Algorithms
- Systems Language Proficiency (Go, Rust, C++)
Data Structures - CodeIntermediateNew
GPU-Parallel Graph Coloring for an EDA Tools Vendor
Implement Jones-Plassmann graph coloring in CUDA (or HIP if AMD hardware available). Input: a 12-million-node graph in CSR format (compressed sparse row). Output: a valid colori…
- Parallel Algorithms
- Gpu Programming
- Cuda
Parallel and Distributed Algorithms - AnalysisIntermediateNew
Exploration Strategies for a Recommendation Bandit
You receive 60 days of anonymized impression/click logs covering around 200 content items and user features (cohort, listening history bucket). Build a contextual-bandit simulat…
- Contextual Bandits
- Thompson Sampling
- Ucb
Reinforcement Learning - CodeBeginnerNew
Reason about Drone Mission Plans with Probabilistic Logic
Build a small Bayesian network (around 12 nodes) capturing weather, no-fly-zone proximity, battery state, operator certification, and mission risk. Implement exact inference (va…
- Bayesian Networks
- Probabilistic Inference
- Knowledge Representation
Introduction to Artificial Intelligence - 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
Plan Warehouse Pick Routes with a Classical Planner
You receive a stylized warehouse map (aisle graph), 30 sample shifts of pick tasks, and the current heuristic's outputs. Write a PDDL domain + problem generator, solve with at l…
- Pddl Modeling
- State Space Search
- Classical Planning
Automated Planning - AnalysisIntermediateNew
Diagnose a Memory-Hierarchy Bottleneck in a Trading-System Hot Path
Receive the normalizer source (around 4,000 lines of C++17), a replay harness that feeds 30 minutes of recorded market data, and host-machine specifications (Intel Xeon Gold 634…
- Memory Hierarchy
- Performance Profiling
- Perf
Computer Systems and Organization - CodeIntermediateNew
RAG Faithfulness Evaluation for a Medical-Education Assistant
You receive 200 student-style questions, two RAG configurations (config A: vector-only + GPT-class generator; config B: hybrid + rerank + GPT-class generator), and the medical-t…
- RAG Evaluation
- Faithfulness
- LLM As Judge
Retrieval-Augmented Generation
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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