Vex

Vex is a cross-platform Markdown desktop editor built with .NET 10, Avalonia 12, Prism, Semi.Avalonia, and Ursa.Avalonia. It focuses on source Markdown editing, native preview, file management, find/replace, export workflows, and copy paths for publishing platforms.

Repository: https://github.com/dotnet9/Vex

Release v1.0.0: https://github.com/dotnet9/Vex/releases/tag/v1.0.0

Vex main window

Positioning

A free and open-source Markdown writing tool. It keeps source editing and preview separate instead of chasing a WYSIWYG editor surface first.
The workspace combines a file/outline sidebar, an AvaloniaEdit Markdown editor, and a CodeWF.Markdown native preview.
The View menu controls sidebar, outline, document list, source mode, line numbers, status bar, fullscreen, and always-on-top behavior.
The File menu covers new/open/open folder/recent files/reopen with encoding/save/export/print/properties/delete/close.
Export supports HTML, PNG, image-based PDF, and Word .docx, including local images, data:image, SVG/WebP conversion, and save-location reveal.
Find/replace supports case matching, whole-word matching, regex, match counts, and debounced scans for long documents.
Theme color, Markdown typography theme, compact layout, and language switching are grouped under the Help menu.
Simplified Chinese, Traditional Chinese, English, and Japanese UI/help documents are included.
The onboarding guide highlights real menu items, tabs, editor, preview, sidebar, and status-bar targets.
Release scripts cover multi-RID publishing, zip packages, SHA256 files, release manifests, and optional Windows MSIX layout packaging.

Features

Feature	Description
Markdown editing	AvaloniaEdit-based source editor with smart new lines, current-line highlight, source mode, line numbers, and formatting inserts.
Native preview	CodeWF.Markdown preview without WebView, covering headings, lists, tables, code blocks, task lists, local images, SVG, and GIF.
File workflow	New documents, single-file open, folder open, recent files, drag-and-drop open, save, save as, external change detection, and reload.
Outline navigation	Builds an outline from Markdown headings and jumps to the selected section.
Find/replace	Case, whole-word, regex, match count, replace next, and replace all.
Export	HTML, PNG, image-based PDF, Word `.docx`, and print preview.
Localization	Simplified Chinese, Traditional Chinese, English, and Japanese through Lang.Avalonia.Json.
Onboarding	CodeWF.AvaloniaControls Guide steps can target menus, TabItems, editor, and preview areas.
Packaging	Windows, Linux, and macOS RID publishing, release zips, SHA256 files, and optional MSIX packaging.

Demo

The typical Vex workspace uses a file/outline sidebar, source editor, and live preview.

Editing and live preview

Outline navigation is useful for long documents.

Outline navigation

Source mode temporarily hides the sidebar and preview.

Source mode

File actions and export paths live in the title menu.

Find/replace includes the common match options.

Find and replace

Theme color, typography, and language can be combined.

Theme and language

The first-run guide targets real controls and menu items.

Onboarding

Project Layout

src/
  Vex/                         Desktop app, Shell, Workspace, Help, services, and ViewModels
  Vex.Controls/                Vex-specific controls
  Vex.Controls.Themes/         Control theme resources
docs/
  Quick start, changelog, acknowledgements, and requirements notes
scripts/
  Stress, release packaging, and MSIX packaging scripts

The application uses Prism for module composition and CodeWF.EventBus for cross-module messages. Markdown preview and export reuse CodeWF.Markdown plus local export services, keeping the writing flow inside native Avalonia controls.

Tech Stack

.NET 10
Avalonia 12
Prism.DryIoc.Avalonia
ReactiveUI.Avalonia
Semi.Avalonia
Ursa.Avalonia
AvaloniaEdit
CodeWF.Markdown
CodeWF.AvaloniaControls
CodeWF.EventBus
Lang.Avalonia.Json

Quick Start

Requirements:

.NET 10 SDK

git clone https://github.com/dotnet9/Vex.git
cd Vex
dotnet restore Vex.slnx
dotnet build Vex.slnx
dotnet run --project src/Vex/Vex.csproj

Create release artifacts:

.\publish_vex_all.bat --package

Repository and Releases

Repository: https://github.com/dotnet9/Vex
Release: https://github.com/dotnet9/Vex/releases/tag/v1.0.0