Version 1.6.0

The interactive narrative design tool that’s free

Ripple Effect is a desktop application for writing branching narrative. You lay passages out on a canvas, wire each choice to what it leads to, and press play to walk the result — over a folder on your own disk.

Download See it in action

Free, and there is no account to make. Every platform, and how to install

Early days — you may still meet the odd rough edge.

For game developers

Story logic you can drop into any engine

Bindings for TypeScript, C and C++, C# and Dart, a C ABI for anything else, and a story that talks with your game both ways — so a choice can be a place, a person or a moment, not just a button.

For writers and narrative designers

Write prose, and keep the structure in view

Spelling and grammar checked and dictation heard on your own machine, house-style rules you write yourself, and a map of how every chapter hands the story on.

For tabletop players and storytellers

Storyboard the campaign, and track everything in it

Characters, items and factions as entities with typed attributes, console variables for the state of the world, and the dice on the board.

What it is

An editor for stories that branch

Interactive narrative — a game’s dialogue, a visual novel, a gamebook, a tabletop campaign — is a story where the reader’s choices decide what comes next. Ripple Effect is a desktop tool for writing one, testing it, and handing it to whatever will play it.

Start

The lamp room

the-keeper-the-lamp-room

The lamp hasn’t been lit in three nights. Below the tower the bell on the reef is ringing with nobody to ring it, and the boat you came in has slipped its rope.

Climb to the lamp

Go down to the shore

Drag out for a new choice

Light in the window

The tide takes the boat

Write

A passage is prose in Markdown, set like a book, in as many languages as the story needs.

Wire

Each passage is a card on a canvas, and every choice is a wire to what it leads to.

Play, then ship

Press play to walk the story as a reader would. When it is ready, its engine plays it in your game, site or app.

Why this one

What sets it apart

Local, native, fast

Your story lives on your disk, not in a browser tab

Ripple Effect is a desktop application, and a project is a folder you already have. The app writes no scaffold into it and claims no ownership: open a directory and it is a project.

No account to make, and no project uploaded anywhere
Editing, playing and checking your spelling all happen on your machine, online or not
A native canvas that draws a zoomed-out board as sketches, so a big one stays quick
Cloud features are planned as an option, never a requirement

The Keeper — Ripple EffectOffline

Explorer

the-keeper
chapters
act-one.graph.json
act-two.graph.json
passages
scripts
notes.md

~/Stories/the-keeperSaved

Scripting and game systems

The systems a game needs, built in

Entities with typed attributes, console variables and host callbacks are part of the story’s model, not a convention you rebuild in every project. Where a wire is not enough, Python is.

A sandboxed Python subset, in Script nodes and inside the prose itself
Components and entities: describe a goblin once, spawn six
Typed console variables, watched live while the story plays
Callback events that tell your game what the story just did

weather.py

# weather.py — how hard the storm blows tonight
keeper = component("Keeper")
gust = roll + keeper["nerve"]

if gust > 15:
    storm = "gale"
else:
    storm = "squall"

Keeper · entity

nerve	int	4
lantern	bool	true
pack	list<string>	[3 items]

Console variables

lamp_oil	int	3
storm	string	squall
bell_rung	bool	false

Fits your pipeline

Built to sit inside the tools you already use

Boards are JSON, prose is Markdown and scripts are .py — every one opens in an editor you already trust and keeps working if this app disappears. And agents, in your terminal or on your desktop, can read and edit a project through its MCP server.

Stable ids and relative paths, so a change reads as a change in review
Version control built into the editor, over the repository you already have
A compiled campaign is a folder a build pipeline reads without the editor

act-one.graph.json
a board
en.md
a passage, per language
weather.py
a script
.git
your repository

chapters/the-lighthouse.graph.json+6

   "connections": [
     {
       "id": "connection_4",
       "type": "default",
       "from": { "nodeId": "narration_1", "portId": "choice_0" },
       "to": { "nodeId": "narration_2", "portId": "in" }
     },
+    {
+      "id": "connection_9",
+      "type": "default",
+      "from": { "nodeId": "narration_1", "portId": "choice_1" },
+      "to": { "nodeId": "end_0", "portId": "in" }
+    },

Go down to the shore → The tide takes the boat

Agents

Hand the folder to an agent and keep writing

Ripple Effect is an MCP server. Point Claude Code — or anything else that speaks the protocol — at the project you have open, and it works in the same folder you are working in, on the board you are looking at, while you are looking at it.

project_infoproject_outlinecatalog_findboard_readboard_linkspassage_readcomponent_readsoundscape_readdiagnostics_readtrace_betweentrace_intotranslation_statusnode_typespython_capabilitiespython_evalcampaign_startcampaign_statecampaign_choosecampaign_answercampaign_tracecampaign_autoplaycampaign_end

passage_createpassage_writecomponent_writeboard_add_passageboard_add_nodeboard_connectfile_createsaveboard_set_nodeboard_set_choiceboard_disconnectboard_remove_nodefile_movefile_deletesoundscape_setsoundscape_add_clipsoundscape_set_clipwriting_readgrammar_checkdictionary_editstyle_rule_writestyle_rule_delete

44 tools, plus nine resources and two prompts. Everything that writes is behind the second switch.

Claude

ChatGPT

Gemini

Ollama

Anything else

Two switches, both off

Agent access makes the app listen at all. Agents may edit is separate and subordinate to it. Neither is on when you install.

A socket, never a port

The server is inside the running app, reached over a local socket by a bridge the client spawns. Nothing is listening on the network.

Edits go where yours go

A board is changed through its own session, so the edit lands in your undo stack. Every write says which paths it touched, and posts to Messages.

Roadmap

What is shipped, and what is next

Each release is a pack of features with a name. The order is the order they are planned in — there are no dates here, because the honest thing to say about a version that has not started is what it is, not when it lands.

1.0

Tavern Meetup

Shipped

Boards on an infinite canvas, passages in every language, components with typed attributes
Control flow, random numbers and Python in the prose
Playable campaigns, script navigation, tracing every route between two passages

1.2

Mimic Chest

Shipped

Version control built in, with nothing to install
An MCP server, so an assistant you already use can read and change the project
In-app updates that fetch and open the right installer

1.3

Homebrew Rule

Shipped

The story runs without the editor: campaigns compiled for a runtime, as Markdown or HTML
State with no wire: console variables, state machines, gates, saved games
Macros, dice, an Input node, and reading time in fifty-four languages

1.4

Elven Choir

Shipped

Soundscapes: a timeline of music and sound a passage brings, and keeps until another replaces it
Sound effects from a node or from Python, and media switches on export
Project templates, metadata on every node, a play window that fills the app

1.5

Multiclassing

Shipped

The story engine in Rust, released on its own for desktop, phones and the web, with host callbacks
A workspace like a code editor's: docking tabs, find and replace in project, a menu bar, Zen Mode
Boards that say what is wrong with them, passages that take arguments, and the app in Italian

1.6

Grammar Lich

Current

Spelling, grammar and style rules of your own, checked on your machine, with a dictionary per project
Dictation on your computer by NVIDIA's Nemotron models, in English or in 32 languages
Countdowns on choices, and stories that read the time, where you are and the reader's language

1.7

Illusion School

Paid tier

Integration with the Recraft V2 API
LLM integration for generative narration

1.8

Party Gathering

Paid tier

Real-time collaboration

2.x

World Smith

Paid tier, across the 2.x releases

Timelines and storyboarding
Indoor and outdoor maps
World wiki

1.0

Tavern Meetup

Shipped

Boards on an infinite canvas, passages in every language, components with typed attributes
Control flow, random numbers and Python in the prose
Playable campaigns, script navigation, tracing every route between two passages

1.2

Mimic Chest

Shipped

Version control built in, with nothing to install
An MCP server, so an assistant you already use can read and change the project
In-app updates that fetch and open the right installer

1.3

Homebrew Rule

Shipped

The story runs without the editor: campaigns compiled for a runtime, as Markdown or HTML
State with no wire: console variables, state machines, gates, saved games
Macros, dice, an Input node, and reading time in fifty-four languages

1.4

Elven Choir

Shipped

Soundscapes: a timeline of music and sound a passage brings, and keeps until another replaces it
Sound effects from a node or from Python, and media switches on export
Project templates, metadata on every node, a play window that fills the app

1.5

Multiclassing

Shipped

The story engine in Rust, released on its own for desktop, phones and the web, with host callbacks
A workspace like a code editor's: docking tabs, find and replace in project, a menu bar, Zen Mode
Boards that say what is wrong with them, passages that take arguments, and the app in Italian

1.6

Grammar Lich

Current

Spelling, grammar and style rules of your own, checked on your machine, with a dictionary per project
Dictation on your computer by NVIDIA's Nemotron models, in English or in 32 languages
Countdowns on choices, and stories that read the time, where you are and the reader's language

1.7

Illusion School

Paid tier

Integration with the Recraft V2 API
LLM integration for generative narration

1.8

Party Gathering

Paid tier

Real-time collaboration

2.x

World Smith

Paid tier, across the 2.x releases

Timelines and storyboarding
Indoor and outdoor maps
World wiki

Open a folder and start writing

No account, no project scaffold, nothing written into your directory that you did not ask for.

Download for free See pricing

The interactive narrative design tool that’s localfree

Story logic you can drop into any engine

Write prose, and keep the structure in view

Storyboard the campaign, and track everything in it

An editor for stories that branch

Write

Wire

Play, then ship

What sets it apart

Your story lives on your disk, not in a browser tab

The systems a game needs, built in

Built to sit inside the tools you already use

Hand the folder to an agent and keep writing

Two switches, both off

A socket, never a port

Edits go where yours go

What is shipped, and what is next

Tavern Meetup

Mimic Chest

Homebrew Rule

Elven Choir

Multiclassing

Grammar Lich

Illusion School

Party Gathering

World Smith

Open a folder and start writing

The interactive narrative design tool that’s free