Formidable is a modular Electron desktop application for creating, managing, and rendering dynamic forms and Markdown documents from YAML-based templates. It combines a visual form editor with a powerful Handlebars-style rendering engine, a built-in virtual file system (VFS), profile switching, and optional Git integration — designed for professionals who need structured content management, versioning, and auditability.
💠 Dedicated to Elly — who lived with strength, humor and clarity.
"Sleep, don't weep - My sweet love" — Damien Rice🌌 And to Aaron Swartz — who refused to back down when it mattered.
"We are all made of stardust, and we are all made of stories." — Aaron Swartz
This version of Formidable is a pre-release for testing and feedback. Expect missing features or bugs. Use at your own risk. See the release notes for details.
Latest Windows Installer: 👉 Formidable Setup.exe (Pre-release)
Comprehensive documentation covering all aspects of Formidable's architecture:
- EventBus System - Event-driven architecture and communication
- Handler Pattern - Domain-specific event handler organization
- IPC Bridge - Main ↔ Renderer process communication
- Plugin System - Extensible plugin architecture
- Virtual File System - Storage organization, auto-sync, and context folders
- Modal System - Resizable modals, split-view, and popup management
- Template & Schema System - Form templates and 20+ field types
- Form System - Form rendering, validation, and operations
- Field GUID System - Dynamic field identification and manipulation
- Template Helpers - Handlebars helpers for rendering (field, loop, math, stats)
- Configuration System - Settings, themes, and profiles
- Global API System - FGA, CFA, and window.api reference
- Documentation Index - Complete documentation hub with quick start guide
📖 50,000+ words of documentation with 200+ code examples
-
⚙️ Dynamic Template & Form System
- YAML-based templates with 20+ field types
- Schema validation and sanitization
- Visual form editor with live preview
- Full Markdown renderer using Handlebars-style syntax
- Field GUID system for dynamic updates
-
🧩 Event-Driven Architecture
- Centralized EventBus for decoupled communication
- 30+ domain-specific handler modules
- Event-driven field operations (CFA.field API)
- Async request-response patterns
-
🔌 Extensible Plugin System
- Backend, frontend, and hybrid plugins
- Declarative IPC registration
- Hot-reloadable plugin architecture
- Plugin SDK with full API access
-
🎯 Global APIs
- FGA (Formidable Global API) - Form and field operations
- CFA (CodeField API) - Dynamic field manipulation from code
- window.api - Secure IPC bridge (100+ methods)
- EventBus - Direct event system access
-
👥 Profile Switching
- Easily switch between multiple user profiles
- Profiles store their own author name, email, context folder, preferences
- Supports collaborative and multi-project use
-
📁 Virtual File System (VFS) → Docs
- Organized storage by context and template
- Full control over storage folders, paths, and metadata
- Auto-synced view of the VFS in the sidebar
- Cache management and event-driven updates
-
🔀 Git Integration (Optional)
- Commit, push, pull from the UI
- Git remote info and branch listing
- Supports Azure DevOps workflows (credential.helper + useHttpPath)
-
🖥️ Clean, Modern UI → Modal Docs
- Resizable, ESC-closable modals with backdrop click dismiss
- Markdown & Preview modal — live output with split/closable panes
- Full light/dark theming, configurable icon or label buttons
- Split-view for template editing and form data
- Inert background and disabled state support
-
🔗 Internal Linking & Wiki Support
- Support for internal form links (
formIdLinkfields) - Future-proof architecture for internal wiki server (localhost)
- Support for internal form links (
-
🔎 Designed for Auditability
- "Auditability by Design" approach: trackable metadata, version control, profile isolation
- Suitable for regulated environments, audit preparation, compliance
Formidable uses a Handlebars-inspired syntax for rendering:
Reference helpers:
{{field "key"}}→ formatted value{{fieldRaw "key"}}→ raw JS value{{fieldMeta "key" "property"}}→ field metadata access
Formidable supports 20+ field types with full schema validation:
| Type | Description | Documentation |
|---|---|---|
text |
Single-line input | Docs |
textarea |
Multi-line text block (Markdown/Plain) | Docs |
boolean |
Checkbox toggle | Docs |
dropdown |
Select from list | Docs |
multioption |
Multiple choice (checkbox group) | Docs |
radio |
Radio button group | Docs |
number |
Numeric input | Docs |
range |
Range slider | Docs |
date |
ISO-style date picker | Docs |
list |
Dynamic list input | Docs |
table |
Editable table grid (JSON) | Docs |
image |
Upload & preview image | Docs |
link |
Text input for URL or link | Docs |
tags |
Tag input field | Docs |
latex |
LaTeX editor with preview | Docs |
code |
Code editor with execution | Docs |
api |
API-linked field with mapping | Docs |
loopstart / loopstop |
Define repeating sections | Docs |
See Template & Schema System for complete field documentation.
Saved to: ./config/user.json
{
"theme": "dark",
"font_size": 14,
"logging_enabled": true,
"context_mode": "storage",
"context_folder": "./",
"selected_template": "my-template.yaml",
"selected_data_file": "example.meta.json",
"author_name": "Regular User",
"author_email": "regular@example.com",
"use_git": true,
"git_root": "./",
"show_icon_buttons": true,
"window_bounds": {
"width": 1280,
"height": 900,
"x": 100,
"y": 80
}
}- Values are validated and auto-repaired on load.
- UI updates are event-driven (
config:update).
git clone https://github.com/petervdpas/formidable.git
cd formidable
npm install
npm startTo build the Windows executable:
npm run buildNote: Current packaging targets Windows. Linux and Mac packaging will be added in future.
- New to Formidable? Start with the Documentation Index
- Building plugins? Check out the Plugin System Guide
- Working with forms? See the Form System and Field GUID System
- Understanding architecture? Read about EventBus and Handler Pattern
- CTRL+ENTER → toggle fullscreen on template editor
- Templates =
.yaml, Data =.meta.json, Images =.jpg/.png - VFS auto-updates on create/save/delete
- Profile switching triggers full config refresh and context rehydration
- Markdown & Preview modal: supports split view and pane closing
- Modals: resizable, ESC-closable, backdrop click dismiss
- Git config per repo is cached
- Event-Driven: All operations flow through EventBus
- Handler Pattern: 30+ domain-specific handler modules
- IPC Bridge: Secure main ↔ renderer communication via contextBridge
- Plugin System: Hot-reloadable with declarative IPC
- Field GUIDs: Every field has a unique identifier for dynamic updates
- Schema Validation: All data validated and sanitized on load
Field Manipulation (from code fields):
// Get field value
const price = await CFA.field.getValue({ key: "price" });
// Set field value
await CFA.field.setValue({ key: "total", value: price * 1.2 });
// Update field options
await CFA.field.updateOptions({
key: "status",
options: ["New", "Active", "Completed"]
});Event-Driven Operations:
// Save form
await EventBus.emit("form:save", {
template: "my-template",
data: formData
});
// Listen to events
EventBus.on("form:saved", (data) => {
console.log("Form saved:", data);
});Plugin Development:
// plugin.json
{
"name": "MyPlugin",
"ipc": { "process": "handleProcess" }
}
// plugin.js
module.exports = {
async run(context) {
// Plugin logic
return { success: true };
},
async handleProcess(event, payload) {
// IPC handler
return { result: "done" };
}
};See Documentation for complete guides and examples.
MIT © 2025 Peter van de Pas
Built with:
- Electron - Cross-platform desktop framework
- CodeMirror - Code editor component
- EasyMDE - Markdown editor
- Handlebars - Template rendering
Special thanks to the open-source community.