The author has created an open-source alternative to Obsidian called Files.md, a simple app for storing notes, documents, and tasks in plain .md files. The app is designed to be local-first, with optional synchronization, and can be easily extended with a large language model (LLM). The author has been using the app for five years and has now open-sourced it. The app has a minimalistic design and is optimized for simplicity and ease of use.