Code Challenges

Build a working backend, frontend, integration, or data pipeline against a real-shaped spec.

DisciplineAll Analysis Code Design Strategy Research Presentation

LevelAll Foundational Beginner Intermediate Senior

SkillsBrowse skill families

CodeIntermediateNew
Integer Programming for Cloud Resource Allocation
Your task is to formulate an integer programming model to select the number of reserved instances (each type: compute, memory, storage) and allocate on-demand instances monthly.…
- Integer Programming
- Python Or Javascript
- Pulp
Operations Research and Optimization
CodeIntermediateNew
Link Prediction for a B2B SaaS Account-Expansion Engine
You receive a CSV of around 80,000 accounts (existing customers + prospects) with attributes (industry, size, tech stack, geography) plus 18 months of marketing-touch and conver…
- Link Prediction
- Node Embeddings
- Node2vec
Machine Learning on Graphs
CodeBeginnerNew
Add Constant Folding and Dead Code Elimination to a Toy Compiler
Fork the repo, read the IR specification (3-address code, register-based, documented in /docs/ir.md). Implement constant folding as an IR-to-IR pass: any operation on literal op…
- Intermediate Representation
- Constant Folding
- Dead Code Elimination
Compiler Construction
CodeIntermediateNew
Variational Autoencoder for Synthetic Tabular Banking Data
You receive a 500K-row anonymized transaction dataset with 25 columns (mixed numerical + categorical). Train a VAE (TabVAE or a small custom model) with appropriate likelihoods …
- Variational Inference
- Deep Generative Models
- Synthetic Data
Probabilistic Machine Learning
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
Design Prompt Versioning and Observability for a Coding Assistant
You will (1) design a prompt-registry data model (versions, owners, environments, change log) and implement it in Postgres + a small Python SDK, (2) instrument the assistant to …
- Prompt Versioning
- Observability
- Pii Scrubbing
LLM Application Development
CodeBeginnerNew
Apply Property-Based Testing to a Currency-Conversion Module
Rewrite the conversion module in F#: use units of measure for currency types, immutable value types for amounts, no floating-point arithmetic (Decimal only). Build property test…
- Fsharp
- Property Based Testing
- Fscheck
Functional Programming
CodeBeginnerNew
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
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
Engineering Software as a Service
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.
Browse challenges
CodeSeniorNew
Video Action Recognition for a Retail Loss-Prevention Startup
Use a public action-recognition dataset (UCF101 + a small curated retail-action subset; the latter is provided synthetic or you can label 50 short clips). Fine-tune a small back…
- Video Understanding
- Action Recognition
- Transfer Learning
Computer Vision
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
CodeIntermediateNew
Train a Differentially Private Classifier on Medical Records
Use Opacus (PyTorch DP-SGD library). Train a tabular classifier (small MLP + gradient-boosted features) with DP-SGD at the agreed epsilon/delta. Run an accuracy-vs-privacy front…
- Differential Privacy
- Dp Sgd
- Opacus
Privacy-Preserving Machine Learning
CodeIntermediateNew
Predict Loan Default Risk for a Cross-Border Fintech
You receive 18 months of transactions (around 12M rows) and seller-firmographic data. Define a defensible proxy label for default (e.g., a 60-day chargeback-or-dispute spike com…
- Feature Engineering
- Model Selection
- Model Evaluation
Applied Machine Learning
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
Temporal Planner for a Robotics Mission Operator
You receive 30 days of mission logs with task lists, time windows, and actual durations. Encode the planning problem with temporal PDDL (PDDL 2.1 durative actions) and solve wit…
- Temporal Planning
- Pddl Modeling
- Simulation
Automated Planning
CodeBeginnerNew
Implement Progressive Delivery with Flagger for an E-Commerce Backend
Install Flagger (or Argo Rollouts) into the existing Kubernetes + Istio stack. Configure canary analysis using Prometheus metrics: request-success-rate, request-duration p99, an…
- Flagger
- Argo Rollouts
- Canary Deployment
GitOps and Continuous Delivery
CodeBeginnerNew
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
Distributional Embeddings for a Multilingual Legal Search
Use a public multilingual corpus (e.g., MultiEURLEX or a subset of EUR-Lex) plus a small hand-built test set of around 100 cross-lingual query-passage pairs. Fine-tune (or evalu…
- Distributional Semantics
- Multilingual NLP
- Sentence Embeddings
Computational Semantics
CodeIntermediateNew
Triage Medical-Imaging Annotations with a Small Vision Model
Train a binary normal/abnormal classifier on the public CheXpert or NIH ChestX-ray14 dataset. Use temperature scaling to calibrate the output, then define abstention thresholds …
- Cnn Classification
- Transfer Learning
- Calibration
Applied Machine Learning
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
Engineering Software as a Service
CodeSeniorNew
Vectorize a Risk-Calculation Engine for a Mid-Cap Bank
Receive the existing pricer (C++17, scalar, around 600 lines), 2 weeks of representative input data (around 50M paths), the validation harness, and access to an Intel Ice Lake-S…
- Vectorization
- Avx 512
- Simd
Performance Engineering of Software Systems
CodeIntermediateNew
Canary Deployments via Mesh Traffic Splitting for a Streaming Platform
Set up Flagger with Istio as the traffic provider. Define a canary policy for the playback-API service: 5 percent → 25 percent → 50 percent → 100 percent with 5-minute bake at e…
- Istio
- Flagger
- Canary Deployment
Service Mesh and Microservices Networking
CodeBeginnerNew
Build a UART Receiver and Loopback on FPGA for an Industrial Sensor Hub
Design a UART receiver in Verilog with 16x oversampling, configurable baud divisor, start-bit detection, 8N1 framing, framing-error flag. Pair with a minimal transmitter for the…
- Verilog
- Uart
- Fpga
Digital Systems Design
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
AI and Quantitative Finance
CodeBeginnerNew
Observability Injection: Distributed Tracing via Sidecars
Enable Envoy tracing with the OpenTelemetry tracer in Istio MeshConfig. Configure a Tempo backend with a Grafana frontend. Verify W3C tracecontext propagation across all 26 serv…
- Distributed Tracing
- Opentelemetry Instrumentation
- API Gateway Patterns (Kong, Envoy)
Service Mesh and Microservices Networking
CodeBeginnerNew
Build an Interactive Carbon-Emissions Explorer for a Climate Nonprofit
You receive 20 years of harmonized European industrial emissions data (around 800,000 rows: country, sector, sub-sector, year, emissions in tons CO2e). Design and build an inter…
- Interactive Visualization
- D3
- Observable
Data Visualization

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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
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Code Challenges | Ewance