What is Fylune?

Fylune is a cross-platform document editor built around real files. It edits Markdown, MDX, JSON, and JSONL files locally on desktop, keeping files readable by Finder, Git, and AI tools. It also lets you fill supported official PDF forms in the browser and save them to your Fylune cloud account. The core editor is free, with paid plans for optional cloud and advanced collaboration services.

How to use Fylune?

Download the Fylune desktop app (macOS Alpha available) and open an existing project folder to start editing Markdown, MDX, JSON, and JSONL files locally — no account required for the core editing loop. Drop or paste images, video, and documents and Fylune files them locally with portable relative paths. For official PDF forms, use the browser-based form templates, fill them online, and save them to your Fylune account. Optional AI edits appear as reviewable changes you can accept or reject.

Core features of Fylune

Local-first editing of Markdown, MDX, JSON, and JSONL files
Free core editor with unlimited local documents, search, and file navigation
Automatic asset management with portable relative paths
Rich previews: Mermaid flowcharts, mind maps, KaTeX formulas, GFM tables, checklists, code, media, and MDX blocks
Reviewable AI changes with conflict-safe atomic writes
Online filling of official PDF form templates saved to your Fylune account
Offline by default with no account required for core editing