A generic hash table implementation with pluggable hash and comparison functions. It supports insertion, lookup, deletion, iteration, and resizing. The implementation is self-contained (only depends on standard C and internal memory allocation) and can be extracted for use in any C project requiring a dynamic hash table.

An interval-based set ADT for storing ranges of integers (e.g., protocol message types). Provides operations for adding, removing, testing membership, and iterating over ranges. The implementation is header-only and uses a simple sorted array of intervals. It is reusable for any application needing efficient range membership tests.

A portable SHA-1 hashing abstraction that supports multiple backend implementations (libmd, CommonCrypto, CryptoAPI, libnettle, libgcrypt, libsha1, OpenSSL). It provides a unified API (xsha1_init, xsha1_update, xsha1_final) and automatically selects the best available backend at compile time. This is a clean, reusable component for any C project needing SHA-1 hashing without tying to a specific library.

A Python module that implements a minimal X11 client capable of connecting to an X server, sending raw protocol requests, and parsing replies. It handles byte-order negotiation, request sequencing, and reply reading. This is a reusable foundation for building X11 protocol tests or tools without requiring a full Xlib binding. The code is clean, well-structured, and demonstrates deep understanding of the X11 wire protocol.

Implements a shadow framebuffer layer that maintains a secondary framebuffer and updates the primary display via a callback function. It supports rotation, reflection, and partial updates. The design uses function pointers for the update routine, making it adaptable to different display hardware. This pattern is reusable for any system requiring double-buffering or framebuffer composition with custom update logic.