Introduction

laykit is a production-ready Rust library for reading, writing, and manipulating GDSII and OASIS IC layout files.

What it does

• Read and write GDSII (.gds) files — the industry-standard binary format for IC layouts
• Read and write OASIS (.oas) files — the modern, more compact replacement
• Convert bidirectionally between the two formats
• Perform geometric operations: bounding boxes, transforms, polygon area/perimeter, point-in-polygon, fillet, fracture
• Boolean polygon operations: union, intersection, difference, XOR, slice, offset
• Generate complex shapes: FlexPath with configurable joins/caps, arcs, Bezier curves, ellipses, splines, spirals
• Manage cell hierarchies: flatten, dependency ordering, cycle detection, library merge
• Stream large files without loading them fully into memory

Design

• Zero external dependencies — pure Rust std only
• 164 tests, 0 failures
• Idiomatic Rust: Result-based error handling, enums for element types, no unsafe code in public API
• Rust edition 2024

Features

• ✅ GDSII read/write (all 7 element types)
• ✅ OASIS read/write (all element types)
• ✅ Bidirectional format conversion
• ✅ Geometry module
• ✅ Boolean operations
• ✅ FlexPath and curve primitives
• ✅ Cell topology utilities
• ✅ Streaming parser
• ✅ AREF expansion
• ✅ Property management
• ✅ CLI tool (convert, info, validate)
• ✅ File format detection by magic bytes