If time allows, I enjoy writing software:

• Java:
  • mockneat - A modern faker lib;
  • neat-sample-database-generators - Generate database data;
  • markovneat - Markov chains;
  • neat-chess - UCI client for calling Stockfish from Java;
  • JVBE - Additional annotations for Java Bean Validation API;
  • ansiscape - Color your stdout.
  • aleph-formatter - String.format() with named arguments;
  • jasuggest - Simple auto-suggesting lib;
  • open-addressing-java-maps - Map<K,V> implementations using Open Addressing;
  • mphmap - Minimal perfect hashing in Java
• Kotlin
  • mapneat - JSON transformers;
  • serverneat - HTTP Server Stub/Mock;
• C:
  • nml - Linear algebra matrix library
  • lc3-vm - Simple register-based VM
  • nmlib - My first open source project, written 12 years ago, was filled with bugs.
  • c-generic-pqueue - A generic PQueue in C
  • chained-hash-table-c - Chained Hashtable in C
  • open-adressing-hash-table-c - Open Addressing Hashtable in C
  • bloomfilters-c - Simple C implementation for bloom filters, code associated with this article.
  • microblog-c - A blog that is one executable.
  • integers-snake - A snake game that uses only 4 integers.
• python:
  • pysert - Generate random data based on templates