This document is both a demo and an executable smoke test.

Open it in the TUI with upmd DEMO.md and press Enter on any block to run it. Run one named block without the TUI with upmd --cli --block stream --yes DEMO.md.

A regular shell command. Select it and press Enter.

ls

Plain text, bold, italic, strikethrough, inline code, a link, and .

Styles can be nested: bold italic, a bold link, and struck italic.

A standalone image renders in the preview pane:

• A list item with bold, italic, strikethrough, and inline code.
• A linked image: .

Inline tags render with HTML syntax highlighting and keep their source text: a bold tag, an emphasis tag, a
self-closing tag, and a

A complete HTML block is shown verbatim, line by line:

Output appears inline while the block runs. The preview follows new rows only when they extend below the viewport.

printf 'Starting demo'
for step in 1 2 3 4; do
  sleep 0.15
  printf '.'
done
printf '\nReady.\n'

Every block runs in a real PTY, so ANSI escape codes and Unicode render correctly.

printf '\033[31mred\033[0m \033[32mgreen\033[0m \033[33myellow\033[0m \033[34mblue\033[0m \033[35mmagenta\033[0m \033[36mcyan\033[0m\n'
printf 'Unicode: café ภาษาไทย 🚀 ★\n'
printf 'Bold: \033[1mimportant\033[0m  Dim: \033[2mquiet\033[0m  Underline: \033[4mlink\033[0m\n'

Shell runners carry exported variables and the final working directory into later blocks.

export UPMD_DEMO_MESSAGE="state carried from the previous block"
export UPMD_DEMO_COLOR="cyan"
export UPMD_DEMO_COUNT="3"
cd "${TMPDIR:-/tmp}"
printf 'Saved environment and cwd: %s\n' "$PWD"

The next block reads the state captured above.

printf 'Message: %s\n' "$UPMD_DEMO_MESSAGE"
printf 'Color: %s\n' "$UPMD_DEMO_COLOR"
printf 'Count: %s\n' "$UPMD_DEMO_COUNT"
printf 'Working directory: %s\n' "$PWD"

Python inherits state captured by the shell block.

import os

message = os.environ.get("UPMD_DEMO_MESSAGE", "missing")
print(f"Python received: {message}")
print(f"Unicode and ANSI stay intact: café ภาษาไทย")
print(f"Count from shell: {os.environ.get('UPMD_DEMO_COUNT', '?')}")

JavaScript also picks up the captured environment.

const msg = process.env.UPMD_DEMO_MESSAGE || 'missing';
console.log(`JavaScript received: ${msg}`);
console.log('Node version:', process.version);

upmd also supports TypeScript, Ruby, PHP, C, Go, Rust, Zig, Fish, Zsh, Cmd, and PowerShell when their executables are installed.

Blocks with a name attribute are selectable by name or numeric ID.

printf 'This block is named "named".\n'
printf 'Jump to it with: upmd DEMO.md --block named\n'
printf 'Or press ctrl-g in the TUI and type "named".\n'

Dependencies run first and pass their captured environment and working directory to dependents.

sleep 1; export BIN_PATH="/tmp/demo"
printf 'build: BIN_PATH=%s\n' "$BIN_PATH"

sleep 0.3; export LINT_REPORT="all clean"
printf 'lint: %s\n' "$LINT_REPORT"

sleep 0.6; export TEST_STATUS="47 passed, 0 failed"
printf 'test: %s\n' "$TEST_STATUS"

read CONFIRM
printf "bin: $BIN_PATH, lint: $LINT_REPORT, test: $TEST_STATUS\n"
printf 'verify: complete (%s).\n' "$CONFIRM"

build runs first. lint and test then run in parallel; verify waits for both.

Run an interactive prompt and press i to send it input:

read -p "Your name: " ME
echo "Hi, $ME!"

Full-screen programs work inside the preview:

nvim

• i focuses the selected process; ctrl-o leaves input mode.
• o opens the full output view.
• f browses Markdown files; typing filters the list.
• ctrl-r reloads the active file and clears prior output.
• t selects a theme; ctrl-t toggles the terminal background.
• e inspects or edits captured environment state.
• ' toggles the dependency graph while a workflow runs.
• ? opens the searchable keymap reference.
• Mouse input, wheel scrolling, drag selection, and ctrl-v paste work in PTY views.

Print every configurable key and default binding:

upmd --dump-default-config 2>/dev/null | head -20 || echo "dump-default-config unavailable"