ascdraw

I value ascdraw at $9.99 or €9.99 for a personal license. It is GPLv3 software, so payment is entirely optional. If it is useful to you, please fund its development.

Native, keyboard-first diagramming for people who think in text.

ascdraw is an effectively infinite Unicode canvas for connected lines, symbols, shapes, text, rectangular editing, layers, and TXT/JSON/PNG export. It is usable today, but its interfaces and document format are still evolving. The canvas renders at 120+ FPS, which matters more than you might think in a keyboard-first editor.

Changelog

• 2026-10-04 — Added morphable Objects: reusable rectangles that stretch, anchor, and keep local edits per copy.

demo-small.mp4

Get it

Download a current nightly from GitHub Releases, or build it yourself with the Rust toolchain managed by mise:

cargo build --release --locked
./target/release/ascdraw

Install from a checkout instead:

cargo install --path . --locked

The Linux nightly is built on Ubuntu 22.04, so it needs glibc 2.35 or newer. On an older distribution, build from source.

Use it

ascdraw opens in Stamp mode. Numbered menus show their own keys; this table covers the less obvious shortcuts. Directions are arrow keys or h, j, k, l.

Action	Key
Move	direction
Draw/apply tool	Ctrl + direction
Place stamp / preview line or shape	Space
Select rectangle	Shift + direction
Erase / move selection	Alt + direction (moves when selection is expanded)
Text mode	i
Continuous replace mode	Return or Shift + R
Replace once	r, then a character
Jump across canvas	m, then direction
Clear selection	Backspace
Undo / redo	u / U or Ctrl/Cmd + Z / R
Copy / cut / paste	Cmd + C / Ctrl/Cmd + X / Ctrl/Cmd + V
Cancel	Escape, Ctrl + C, or Ctrl + G

• Stamp: place symbols, arrows, fills, and blocks. Copy one cell to use its glyph as a custom stamp until you select a bundled stamp.
• Line: draw connected Unicode lines; Space starts a routed preview.
• Shape: draw outlined or filled rectangles. Each rectangle becomes an object anchored in its corners.
• Utils: push/pull rows and columns, or pan the viewport.
• Objects (1 5): reuse a rectangle as a template. See Objects.
• Files/Togls (0): load, save, export, change theme, and enable colors or layers.

Optional features:

• Color: choose from 16 ANSI-style colors for new text and drawing. PNG and JSON preserve colors; TXT does not.
• Layers: add, hide, reorder, and merge layers. Editing affects the active layer; PNG preserves the visible stack.
• Dark Mode: available, but less polished because I prefer and primarily use black on white.

In Line mode, Space starts a routed preview; move to route, Space commits an anchor, and Space again finishes. Backspace removes the last anchor and Escape cancels the live segment.

Modifier order matters. The first chooses the action; the second changes its distance:

First held	Action	Add for 5 cells	Add for 10 cells
Shift	Select	Ctrl	Alt
Alt	Erase	Ctrl	Shift
Ctrl	Draw/apply tool	Alt	Shift

Objects

An object is a saved rectangle. Every copy follows the definition, and each copy keeps its own local edits on top.

Key	Action
2 Dfn	Save the selection as an object and open DfnEdt on it.
3 Edt, then 1 Dfn	Edit the definition through the copy under the cursor (DfnEdt). Every copy updates.
3 Edt, then 2 Lcl	Edit the local copy under the cursor (Edt). A space paints the cell empty, hiding the definition and anything below; it shows as a dimmed cell. Definition cells show dimmed.
3 Edt, then 3 Res	Reset the copy under the cursor to its definition: no local edits, stretch, or growth.
4 Anchr, then 1–9	In DfnEdt, attach an anchor at the cursor: W NW N NE E SE S SW or ·. Backspace on an anchor deletes the anchor; a second Backspace clears the cell.
Space	Place a copy of the last defined object.
Alt + direction / Alt-drag	Decided where the gesture starts: on text it only erases; on a copy (or the empty part of its box) it only moves the copy.
Double-click a copy	Open Lcl on it.
Ctrl + click a copy	Outside DfnEdt and Edt, dissolve the copy into plain text; the definition goes with its last copy.
Drag a copy edge or corner	In any mode outside DfnEdt and Edt the pointer turns into a resize arrow over an edge or corner; drag to resize from there.
Ctrl + direction	Outside DfnEdt and Edt, stretch the copy under the cursor. Toward the far side of its center the edge on that side grows; toward the center the opposite edge shrinks. Only that copy changes.
Backspace	Outside DfnEdt and Edt, clear text over the copy under the cursor; with nothing above, remove the copy.
Cmd + C, Cmd + V	Outside DfnEdt and Edt, on a copy, copy it; paste places a copy with the same local edits. Inside them Cmd + C copies cells.

DfnEdt and Edt dim the rest of the canvas and stay on while you switch to other tools. Press Escape in any mode, or the same command again, to leave them. Inside them the copy is ordinary canvas, and writing outside it grows the definition in DfnEdt. Edt never changes the copy boundary. Outside them, copies lie below ordinary text: writing over a copy leaves the copy unchanged, and moving or resizing a copy clears nothing. A selection carries the copies lying wholly inside it.

An object with a single copy has no separate definition: that copy's local edits are the definition. Its size stays a stretch, so resizing never loses structure.

Stretching a copy lengthens connected lines. Implicit groups, cells that touch or letters one space apart, keep their shape and move proportionally. An anchored group keeps its offset instead: W and E fix the distance from that side or from the next anchor in that direction, N and S do the same vertically, the diagonal anchors fix both axes, and · keeps a fixed offset from the nearest anchor.

Scroll or two-finger drag to pan. Pinch or Ctrl/Cmd + scroll to zoom. Most tools also support clicking and dragging.

Edit a native document in place, with normal autosaving:

ascdraw drawing.json

Filter mode reads plain text from stdin, opens it for interactive editing, then prints the result to stdout once the window closes. It does not touch the scratchpad:

ascdraw - < input.txt > output.txt
# or
printf 'box\n' | ascdraw - > output.txt

This also makes ascdraw usable as an external editor filter:

Editor	Command
Kakoune	`
Neovim	:%!ascdraw -
Emacs	`M-

Configure it

Bundled defaults are in ascdraw.toml and theme.toml. Put overrides in $XDG_CONFIG_HOME/ascdraw/config.toml, or ~/.config/ascdraw/config.toml. Changes reload while the app is running. Run ascdraw --show-config to see the merged configuration and searched paths.

Only include values you want to override:

font-family = "SF Mono"
font-size = 14.0
transparent-menubar = true

[jump]
inactivity-ms = 500

[keys]
font-scale-up = "Cmd-="
font-scale-down = "Cmd--"
window-new = "Cmd-N"

[theme.default]
fg = "#000000"
bg = "#ffffff"

[theme.cursor-drawing]
fg = "#00008b"

Colors use #RRGGBB or #RRGGBBAA. Theme faces and all available settings are listed in the two bundled default files linked above.

Develop it

cargo fmt --all -- --check
cargo test --locked --quiet
cargo clippy --all-targets --all-features --locked -- -D warnings

OpenAI GPT-5.5 and GPT-5.6 Sol aided development. Mostly.

License

Copyright (C) 2026 Przemysław Alexander Kamiński vel xlii vel exlee.

ascdraw is released under the GNU General Public License, version 3 or later. Commercial licenses are available where GPL terms are unsuitable; contact [email protected]. See NOTICE for details.