The code examples have been updated in August 2025 to run with Hy version 1.1 (hy-1.010)

The examples are in the directory hy-lisp-python-book/source_code_for_examples.

I am in the process of adding new examples (mostly LLM) and deprecating old examples. The old examples will be moved to the directory hy-lisp-python-book/source_code_for_examples/OLD_EXAMPLES_NO_LONGER_IN_BOOK and removed from the book.

As I am updating this book in August 2025, the latest version of Hy is 1.1.0:

$ hy
Hy 1.1.0 (Business Hugs) using CPython(main) 3.13.3 on Darwin
=> 

You can purchase the book at leanpub or read the book online for free. I offer free updates to new editions to all of my books purchased on leanpub.

This book covers many programming topics using the Lisp language Hy that compiles to Python AST and is compatible with code, libraries, and frameworks written in Python. The main topics we will cover and write example applications for are:

• Relational and graph databases
• Web app development
• Web scraping
• Accessing semantic web and linked data sources like Wikipedia, DBpedia, and Wikidata
• Automatically constructing Knowledge Graphs from text documents, semantic web and linked data
• Deep Learning
• Natural Language Processing (NLP) using Deep Learning
• OpenAI GPT APIs
• LangChain for chaining Large Language Model operations

Please note that this repo may also occasionally contain examples that are a work in progress (these directories conatin a file named NOT_YET_IN_BOOK.md).

If you would like to support my work please consider:

• Hire me as a consultant: https://markwatson.com.
• Purchasing my books on Leanpub: https://leanpub.com/u/markwatson.
• Star my git repositories that you find useful on GitHub: https://github.com/mark-watson?tab=repositories.

You can also interact with me on social media: Mastodon https://mastodon.social/@mark_watson and X/Twitter https://x.com/mark_l_watson.