Interactive Algorithm Tutor

interactive-algorithm-tutor.vercel.app

Paste real Python, Java, or C++ code, run it for real, and watch the correct visualization appear automatically — arrays, linked lists, trees, recursion trees, DP grids, stacks/queues, graphs, and tries. Every step comes from an actual execution trace (Python sys.settrace, Java JDI, C++ via gdb) — nothing is guessed or hard-coded per example.

Quick look

Landing page	Visualizer — live Java trace, step-by-step

70+ written articles with interactive playgrounds for every topic

What it does

• Runs your code in the selected language and captures a full step-by-step execution trace (variables, call stack, loop/branch state).
• Automatically detects the data structures involved and renders the right visualization for each one — no manual configuration.
• Timeline scrubber with play/pause/speed, "key steps only" mode, and per-function focus for deep call stacks.
• 70+ written articles covering the underlying algorithms and data structures, plus 40+ ready-to-run premade visualizations.

Architecture

React frontend (Vite)  --HTTPS-->  Node gateway  --localhost-->  Python worker   (sys.settrace)
                                                  --localhost-->  Java worker     (JDI)
                                                  --localhost-->  C++ worker      (gdb)

The frontend is a static Vite/React app deployed on Vercel. The gateway and the three language workers run together on a single backend host and are process-managed with pm2.

Getting started locally

Requires Python 3.10+, Node 18+, and a JDK 11+ on PATH.

cd backend
pip install -r requirements.txt
uvicorn worker.app:app --host 127.0.0.1 --port 8000     # Python worker

cd backend/java-worker
java JavaWorker.java --serve 8001                        # Java worker

cd backend/cpp-worker
uvicorn app:app --host 127.0.0.1 --port 8002              # C++ worker (needs g++/gdb)

cd backend/Api
npm install && npm start                                  # Gateway, http://localhost:5000

cd frontend
npm install && npm run dev                                # http://localhost:5173

On Windows, start-all.bat / start-all.ps1 launch all of the above in one step.

Deployment

Frontend is deployed on Vercel, built from frontend/. The backend runs on a Linux VM behind Caddy (automatic HTTPS), with VITE_API_URL pointing the frontend at the backend's URL.