Leathercase

Leathercase is a desktop app for novelists and screenwriters. Point it at the folder you already write in and it shows the story's structure, without asking you to re-type anything into a second tool.

It reads Markdown, Obsidian vaults, Word chapters, Scrivener projects and Fountain screenplays where they are, and never changes them. What it adds is small Markdown and JSON files beside your story, readable without the app.

What you get:

• Plot grid: scenes across the top, threads down the side, so you see what you planted, where it returns and where a thread goes quiet.
• Threads: follow one storyline from first mention to last, with plants, payoffs and reversals marked.
• Graph: characters, places, factions and events, and the ties between them.
• Beat board and writer board: cards in lanes named after your structure, and a shared board for references, lines and images.
• Manuscript: the whole draft as one scroll, with lenses for rhythm, style, dialogue and echoes, and comments.

Three promises:

• Your files stay on your computer. It works offline, with no account and no telemetry.
• No AI writes your book. It reads structure with plain rules. You can connect your own assistant over MCP if you want one, and it never writes prose.
• Free, for good. No trial, no locked features. Patrons fund it.

macOS (Apple silicon and Intel) and Linux (AppImage and .deb, x86_64 and ARM64). The app updates itself. The interface is in English and Portuguese. Made by one person, a software engineer learning to write fiction.