Pandora's Gate
Pandora's Gate app icon

Write novels with AI that
actually remembers your story.

A desktop writer's studio for long-form fiction. Run models entirely on your own machine, or bring your own key for remote ones. Your novel stays a folder of plain markdown on your disk — no account, no cloud, no lock-in.

Install for macOS View source
brew install --cask tdarwin/pandora/pandoras-gate

Free and MIT-licensed · macOS 13+ on Apple Silicon · signed and notarized

Long-form fiction breaks AI tools.

A novel outgrows any context window by chapter ten. The assistant that was helpful in chapter one starts contradicting your canon — inventing a sister the character never had, forgetting the magic system caps at tier 7, misremembering who died.

Pandora's Gate is built around that problem. As you write, it maintains a Codex: a structured, readable record of what's true in your story — characters, world and system rules, chapter summaries, a timeline, a glossary. Generated with AI help, reviewed by you, stored as ordinary files, and assembled into context for every request.

The model doesn't need to remember your novel. The app hands it the relevant parts, every single time.

What's in it

True WYSIWYG prose

Bold looks bold, headings look like headings. Markdown is the storage format, never the writing surface. Chapter frontmatter tucks into a collapsible panel above the text.

The Codex

Your novel's canon reference — synopsis, per-chapter summaries, character profiles, world and system rules with LitRPG-friendly structured fields, glossary, timeline. Browsable and editable right in the app.

You approve everything

On save, the AI proposes Codex updates. Review them as tracked changes in the editor — accept or reject each suggestion, keep typing while you decide. Rejected stays rejected.

Local models, first-class

A curated catalog with hardware-aware recommendations and resumable downloads, or import any GGUF. Inference runs isolated from the UI — Metal on Apple Silicon, CUDA/Vulkan/CPU on Windows.

Context you can inspect

Every request assembles story context within a real token budget, and shows you exactly what was included, trimmed, or dropped. Tight budgets go retrieval-first so an 8k local model stays genuinely useful.

Chat that can act

The assistant has tools for creating and drafting chapters, making targeted section edits, and reading or updating Codex documents — every change surfaced for review.

Outline and draft

Outline a chapter, a novel, or a whole series with the model, then have it produce a first draft you rewrite. Assign different models to drafting, copy-edit, developmental notes, and Codex upkeep.

One-paste publishing

"Copy for RoyalRoad" or "Copy for Patreon" puts the chapter on your clipboard shaped for that platform — scene breaks, heading depth, and stat tables adjusted per site. Paste and post.

Nothing is ever lost

Every save auto-commits to a hidden git repo. Browse history, view diffs, restore any version — and restores are new commits, so they're undoable too.

Your novel is just a folder.

Markdown and YAML, human-readable, on your own disk. Any editor can open it. Git can diff it. No database owns it, and nothing stops you from walking away with your work.

The app validates on load and never crashes on a hand-edited file — because you're explicitly invited to edit them. 

my-novel/
├── novel.yaml               # chapter order + status
├── chapters/
│   ├── 001-the-gate.md
│   └── 002-descent.md
└── metadata/
    ├── synopsis.md
    ├── summaries/
    ├── characters/kael.md
    ├── world/magic.md
    ├── glossary.md
    └── timeline.yaml

Install

macOS 13 (Ventura) or later, Apple Silicon.

With Homebrew

This project's repository doubles as a Homebrew tap:

brew tap tdarwin/pandora https://github.com/tdarwin/pandoras_gate
brew install --cask tdarwin/pandora/pandoras-gate

Or download the DMG

Grab the latest build from GitHub Releases and drag it into Applications. Releases are signed with an Apple Developer ID and notarized, so it opens without Gatekeeper warnings.

First run

  1. New Novel — pick a folder. The app scaffolds the structure and initializes the hidden git repo.
  2. Add a model — an OpenRouter key (stored in your keychain, never in a file), or download a local GGUF from the built-in browser.
  3. Write and save. The Codex pipeline proposes summary, character, and world updates for you to review.

Intel Macs and Windows aren't built by CI yet — the Windows target is configured and can be built from source. Building for those in CI is on the roadmap.

Contribute

Pandora's Gate is open source under the MIT license. Bug reports, feature requests, and pull requests are all welcome.

Report a bug

Something broken or behaving strangely? The issue templates ask for exactly what's needed to reproduce it.

Request a feature

Describe the writing problem you're hitting. Disagreements about how the app works are welcome too.

Build from source

Node 22, npm install, npm run dev. The development guide has the full architecture tour.

Open a pull request

Fork, branch, keep tests and typecheck green, describe how you verified it. The contributing guide covers the rest.

Support the project

Pandora's Gate is free, MIT-licensed, and built in the open by one person. If it's useful to you and you'd like to help it keep going, you can back development on Patreon.

Become a patron