Zoi Code.
The LeetCode for VLSI.
Zoi Sandbox is the open module + testbench playground. Zoi Practice lists collections with hidden testbench. Zoi Code is the main graded problem set—all use the same judge pipeline.
Graded structured problems with test scaffolding and judging.
After Run — explore tabs
Build log & simulator prints
Build succeeded.
Simulator output, errors, and $display lines land here after each run.
Integrated Environment
Write, compile, and simulate Verilog/SystemVerilog directly in your browser. No heavy installations required.
Instant Feedback
Get real-time syntax checking and compilation errors. Run testbenches and see results in seconds.
Waveform Viewer
Debug your designs with our built-in EPWave-like waveform viewer. Zoom, pan, and analyze signals effortlessly.
Hardware-Focused
Tailored specifically for digital design. Libraries for standard logic gates, flip-flops, and FSMs included.
Problem Library
Practice with hundreds of curated problems ranging from basic logic gates to complex processor design.
Mock Interviews
Simulate real-time technical interviews with timed coding challenges and automated test cases.