Project Roulette / Projects

Frontend, Backend, Data & ML and Systems projects

14 of 30 projects. Each has a stack, five features to ship, a difficulty, a time estimate, and a bonus challenge.

Frontend · Intermediate · 2 weeks

Accessible Design System & Component Library

A themeable library of accessible UI components (dialog, combobox, tabs, data table, toast) published to npm, with a documentation site where people can try every component live.

  • React
  • TypeScript
  • Storybook
  • Vitest
  • Testing Library
  • axe-core

Features

  1. 8–10 components with full keyboard support and correct ARIA roles
  2. Light and dark theming driven by design tokens
  3. Docs site with a live props playground for each component
  4. Automated accessibility tests that run in CI on every pull request
  5. Versioned releases to npm with a generated changelog

Bonus: Visual regression testing with Playwright screenshots that block a PR if any component changes unexpectedly.

Frontend · Intermediate · 1–2 weeks

Git Repo Time-Lapse Visualizer

Paste any public GitHub repository and watch its file tree grow over time as an animated treemap, with contributor activity and the files that change most often.

  • TypeScript
  • Vite
  • D3.js
  • GitHub REST API
  • Web Workers

Features

  1. Fetch and cache commit history with pagination and rate-limit handling
  2. Animated treemap playback with a timeline scrubber
  3. Contributor timeline and a churn heatmap of hot-spot files
  4. Heavy parsing moved into a Web Worker to keep animation smooth
  5. Shareable URLs that encode the repo and timestamp

Bonus: Export the playback as a WebM or GIF that people can drop straight into their own README.

Frontend · Intermediate · 2 weeks

Browser Logic Circuit Simulator

Drag gates, wires, clocks, and LEDs onto a canvas and watch signals propagate in real time. Build anything from a half adder to a tiny CPU in the browser.

  • TypeScript
  • Canvas 2D or SVG
  • Vite
  • Web Workers
  • Vitest

Features

  1. Drag-and-drop gates, switches, clocks, LEDs, and seven-segment displays
  2. Event-driven simulation with propagation delay
  3. Truth-table generator for any selected circuit
  4. Reusable custom components built from sub-circuits
  5. Save, load, and share circuits by link

Bonus: A waveform timing-diagram viewer that works like a logic analyzer for any wire you probe.

Backend · Advanced · 2–3 weeks

Distributed Background Job Queue

A Redis-backed job system with multiple workers, retries, scheduled jobs, and a dead-letter queue, plus a small dashboard showing what's running and what failed.

  • Go
  • Redis
  • PostgreSQL
  • Docker Compose
  • Prometheus

Features

  1. Enqueue API with priorities and delayed jobs
  2. Exponential-backoff retries and a dead-letter queue
  3. Horizontally scalable workers with graceful shutdown
  4. Idempotency keys that prevent duplicate processing
  5. Metrics endpoint for throughput, latency, and failure rate

Bonus: A chaos test script that kills workers mid-job and proves, with logs, that no job is ever lost.

Backend · Intermediate · 1–2 weeks

Webhook Relay & Replay Service

Receives webhooks from services like Stripe or GitHub, verifies their signatures, stores them, and forwards them reliably to your apps with retries and one-click replay.

  • Node.js
  • TypeScript
  • Fastify
  • PostgreSQL
  • BullMQ
  • OpenAPI

Features

  1. Per-source HMAC signature verification
  2. Durable storage with a searchable delivery log
  3. Retries with backoff and a per-endpoint circuit breaker
  4. Replay any stored event to any endpoint
  5. OpenAPI spec with generated API docs

Bonus: A small CLI that tunnels live events to localhost so developers can test webhooks on their own machine.

Backend · Advanced · 2 weeks

API Gateway with Rate Limiting

A reverse proxy that sits in front of your services and handles authentication, rate limiting, caching, and request logging so the services don't have to.

  • Go
  • Redis
  • JWT
  • Docker
  • k6

Features

  1. Config-driven routing to multiple upstream services
  2. Token-bucket rate limiting per API key, shared across instances through Redis
  3. JWT validation and API key management
  4. Response caching with TTLs and manual invalidation
  5. Structured access logs and latency metrics

Bonus: k6 load tests that publish p50, p95, and p99 latency with and without the gateway in front.

Data & ML · Intermediate · 1–2 weeks

Resume ↔ Job Description Matcher

Upload a resume and a job posting. It scores how well they match, highlights missing skills, and suggests stronger bullet points.

  • Python
  • sentence-transformers
  • spaCy
  • FastAPI
  • Streamlit

Features

  1. PDF parsing and section extraction (experience, skills, education)
  2. Skill extraction against a curated skills taxonomy
  3. Semantic similarity scoring with a readable explanation
  4. Gap report listing missing and weak skills
  5. A small labeled test set that measures accuracy

Bonus: Benchmark three embedding models on your test set and publish the results table in the README.

Data & ML · Intermediate · 1–2 weeks

Webcam Hand-Gesture Controller

Recognizes hand gestures from a webcam in real time and uses them to control slides, media playback, or smart lights.

  • Python
  • MediaPipe
  • PyTorch or scikit-learn
  • OpenCV

Features

  1. Hand landmark extraction from live video
  2. Data-collection tool for recording custom gestures
  3. Trained classifier with a confusion matrix and accuracy report
  4. Smoothing and debounce so actions don't misfire
  5. Config file that maps gestures to actions

Bonus: Export the model to ONNX and run it fully in the browser with a live demo page.

Data & ML · Advanced · 2–3 weeks

Predictive Maintenance for Jet Engines

Predicts the remaining useful life of jet engines from sensor time series using NASA's C-MAPSS dataset, served behind an API with a monitoring dashboard.

  • Python
  • pandas
  • LightGBM or PyTorch
  • MLflow
  • FastAPI
  • Docker

Features

  1. Exploratory analysis and time-series feature engineering
  2. A baseline model and an LSTM, compared with proper time-based validation
  3. Experiment tracking in MLflow
  4. Model served through FastAPI inside Docker
  5. Dashboard showing predictions per engine

Bonus: Data-drift detection that flags when incoming sensor data stops looking like the training data.

Data & ML · Intermediate · 2 weeks

Codebase Q&A Assistant

Index any Git repository and ask questions like "where is authentication handled?" Answers cite the exact files and lines they came from.

  • Python
  • tree-sitter
  • sentence-transformers
  • pgvector or Qdrant
  • FastAPI
  • An LLM API

Features

  1. Code-aware chunking by function and class using tree-sitter
  2. Hybrid keyword and vector search
  3. Answers with file and line citations
  4. Incremental re-indexing when new commits land
  5. An evaluation set of 30+ questions that measures retrieval accuracy

Bonus: A VS Code extension so you can ask questions without leaving the editor.

Systems · Advanced · 2–3 weeks

LSM-Tree Key-Value Store

A persistent key-value database built from scratch with a write-ahead log, memtable, SSTables, and compaction, like a tiny RocksDB.

  • Rust or C++
  • TCP
  • criterion / Google Benchmark

Features

  1. Write-ahead log with crash recovery
  2. Memtable flushed to sorted SSTable files
  3. Bloom filters to skip unnecessary disk reads
  4. Background compaction
  5. Simple TCP protocol with a CLI client

Bonus: Benchmarks against SQLite with throughput and latency graphs in the README.

Systems · Advanced · 2–3 weeks

RISC-V Emulator with Debugger

An RV32I CPU emulator that runs real programs compiled with GCC, plus a step debugger for registers and memory.

  • C++ or Rust
  • RISC-V GCC toolchain
  • SDL2 (optional)

Features

  1. Fetch, decode, and execute for the full RV32I instruction set
  2. ELF loader for compiled binaries
  3. Memory-mapped UART so programs can print
  4. Step debugger with register and memory views
  5. Passes the official riscv-tests suite

Bonus: A 5-stage pipeline view that visualizes hazards, stalls, and forwarding cycle by cycle.

Systems · Advanced · 2–3 weeks

Mini Container Runtime

Your own version of docker run, built from scratch: isolated processes with their own filesystem, process tree, network, and resource limits.

  • Go or C
  • Linux namespaces
  • cgroups v2
  • OverlayFS

Features

  1. PID, mount, UTS, and network namespaces
  2. Root filesystem set up with pivot_root from an image tarball
  3. CPU and memory limits using cgroups v2
  4. Layered filesystems with OverlayFS
  5. veth networking so containers can reach the internet

Bonus: Pull and run real images from Docker Hub by implementing the registry API.

Systems · Advanced · 2–3 weeks

Compiler for a Small Language

A compiler for your own small language, with variables, functions, loops, and structs, that outputs WebAssembly or x86-64 assembly and runs real programs.

  • Rust, C++, or OCaml
  • WebAssembly (WAT) or x86-64
  • A test harness

Features

  1. Hand-written lexer and recursive-descent parser
  2. Type checker with clear error messages that point at the source
  3. An intermediate representation with constant folding and dead-code elimination
  4. Code generation to WebAssembly or assembly
  5. Test suite of example programs with expected output

Bonus: A web playground that compiles and runs programs right in the browser.