Marker

Fast, minimal PDF annotation, built to stay out of the way.

Marker is a desktop PDF annotator written in Rust with egui/eframe and MuPDF. Open a document, mark it up, and keep moving.

Features

• Highlight text; add text, rectangles, ellipses, and lines.
• Typeset math annotations from LaTeX via Typst (see Math / LaTeX).
• Paste images directly from the system clipboard.
• Work across tabs with document outlines, search, and recent files.
• Navigate with the mouse, trackpad, page keys, or Vim-style motions.
• Undo and redo edits; changes auto-save back into the PDF.
• Keep the interface spare with a slim toolbar, a hideable tools strip, and fullscreen zen mode.
• Adjust annotation color, text size, or stroke width from an inline style bar.
• Follow the OS light/dark preference (and GNOME accent color on Linux).
• Split tabs side-by-side or stacked with a draggable divider.

Build from source

Marker requires a stable Rust toolchain. From a checkout:

cargo run --release

Pass one or more PDFs to open them immediately:

cargo run --release -- document.pdf other.pdf

On Linux, a second launch forwards paths to the running Marker window and opens them as tabs (single-instance). Force a separate window with --new-window (or -n), or use the desktop action Open in New Window. From a tab’s right-click menu, choose Move to new window to detach that document.

To build without running:

cargo build --release
./target/release/marker document.pdf

Linux: install as default PDF app

Build a release binary, install it under ~/.local, register the desktop entry, and set Marker as the default handler for application/pdf:

./packaging/install-local.sh

Re-run the same command after pulling changes to rebuild and update the installed binary. To install a binary you already built, pass its path:

./packaging/install-local.sh ./target/release/marker

Linux dependencies

The current MuPDF configuration links its codec and font libraries through pkg-config and uses bindgen. On Debian or Ubuntu, install the build tools and development packages with:

sudo apt install build-essential pkg-config libclang-dev \
  libfontconfig1-dev libfreetype6-dev libharfbuzz-dev libjbig2dec0-dev \
  liblcms2-dev libjpeg-dev libopenjp2-7-dev libbrotli-dev zlib1g-dev

Package names vary on other distributions.

Usage

Open a PDF with Ctrl+O, by dropping it onto the window, or by passing its path on the command line. Marker writes annotations directly into the opened PDF and auto-saves after a short idle period; Ctrl+S saves immediately.

Tools

Key	Tool
S	Select text or objects (drag empty space to marquee-select by center), move, and resize
H	Highlight
T	Text
R	Rectangle
E	Ellipse
I	Line
M	Math
Ctrl+Shift+V	Paste an image from the clipboard

Shortcuts

Shortcut	Action
Ctrl+O	Open a PDF
Ctrl+S	Save now
Ctrl+F or /	Search
N / Shift+N	Next / previous search result
Ctrl+W	Close the current tab
Ctrl+Tab / Ctrl+Shift+Tab	Switch tabs
Tab	Exit $…$ / $$…$$ math in a text box and continue typing
Ctrl+Z	Undo
Ctrl+Y or Ctrl+Shift+Z	Redo
Ctrl+Shift+B	Show or hide the tools strip
F11	Toggle zen mode
Click title / Ctrl+Tab	Open or cycle tabs
Drag tab (title or list) to viewport edge	Split side-by-side (left/right) or stacked (top/bottom)
Right-click title or tab in list	Split side-by-side / stacked / with…, unsplit, or move to a new window
Ctrl+\ / Ctrl+Shift+\	Toggle side-by-side / stacked split with next tab
Ctrl+Alt+\	Focus the other split pane
Ctrl+Alt+I	Toggle Cursor assistant (hiding keeps the chat session)
Ctrl+= / Ctrl+-	Zoom in / out
Ctrl+0	Fit width, then fit height
Ctrl+G	Jump to a page
Ctrl+Shift+Enter	Insert a blank page after the current page
Ctrl+C	Copy selected page text (or highlight / text annotation)
Delete or Backspace	Delete the selected annotation(s)

Vim-style navigation uses J/K to pan vertically and L/Shift+L to pan horizontally (H is Highlight), plus Ctrl+U/Ctrl+D for half-page movement, gg for the first page, and G for the last. Numeric counts work with these motions.

Math / LaTeX

Text annotations accept inline math with $...$ and display math with $$...$$ (literal dollars: \$). When the caret is inside a math island, a LaTeX editor opens with a live preview; Tab closes the island (if needed) and continues with normal text after it. On save, Marker keeps the full source on the text annotation and writes each equation as a separate math stamp for other PDF readers.

Standalone math annotations (M) still accept a LaTeX math subset (converted with MiTeX, rendered with Typst). Wrappers like $...$, $$...$$, \(...\), and \[...\] are stripped automatically. Click away or press Escape to leave the field; Ctrl+Tab still switches document tabs.

Supported (common constructs):

• Fractions: \frac{a}{b}
• Roots: \sqrt{x}, \sqrt[n]{x}
• Greek letters, superscripts/subscripts, \pm, \dots, \vdots, \ddots
• Delimiters such as \langle, \rangle, \left, \right
• Matrices: matrix, pmatrix, bmatrix, Bmatrix, vmatrix, Vmatrix
• Alignment: aligned, align, gathered, gather, split (and *at variants)
• Styling helpers: \mathbf{...}, \operatorname{...}, \overbrace{...}, \underbrace{...}

Known gaps: full LaTeX packages, custom macros, and MiTeX helpers without a native Typst rewrite may fail to compile.

Configuration

Marker stores config.toml in the platform config directory provided by the Rust directories crate:

• Linux: ${XDG_CONFIG_HOME:-$HOME/.config}/marker/config.toml
• macOS: ~/Library/Application Support/marker/config.toml
• Windows: %APPDATA%\marker\config\config.toml

The file contains annotation style defaults, tools-strip visibility, and the recent-files list.

License

Marker is released under the MIT License.