Project Roulette / Projects

Backend, Mobile and Data & ML projects

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

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.

Mobile · Intermediate · 2–3 weeks

Offline-first Field Inspection App

A mobile app for technicians who inspect equipment on site: checklists, photos, and signatures that work with no signal and sync later.

  • React Native (Expo)
  • TypeScript
  • SQLite
  • Supabase

Features

  1. Dynamic checklist templates loaded from the server
  2. Photo capture with on-image annotation
  3. Local-first storage with background sync and conflict handling
  4. Signature capture and PDF report export
  5. GPS-tagged inspections

Bonus: A small web admin dashboard where managers create templates and review submitted inspections.

Mobile · Intermediate · 2 weeks

Bluetooth LE Sensor Companion App

A phone app that discovers a Bluetooth Low Energy sensor, streams live readings, keeps a history, and sends settings back to the device.

  • Flutter (Dart)
  • flutter_blue_plus
  • SQLite
  • ESP32 or nRF52 as the peripheral

Features

  1. Scan, connect, and auto-reconnect to the device
  2. A custom GATT service and characteristics that you define
  3. Live charts of incoming readings
  4. Local history with CSV export
  5. Write settings like sample rate and thresholds back to the device

Bonus: Firmware updates delivered over Bluetooth straight from the app.

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.