Par Term Emu Core Rust

A comprehensive terminal emulator library written in Rust with Python bindings for Python 3.12+. Provides VT100/VT220/VT320/VT420/VT520 compatibility with PTY support, matching iTerm2's feature set.

What's New

Note: For the complete release history, see CHANGELOG.md. The entries below cover the most recent releases; the full history for older versions lives in CHANGELOG.md.

Version 0.58.0 is a minor release with breaking changes for C/Swift and Rust embedders: the C FFI lands its v4 ABI revision — every export is ptec_-prefixed, SharedCell colors resolve through the live palette with ptec_terminal_read_cell_grapheme for full graphemes, and observers receive structured on_event_v2 events — plus v5 scroll-aware damage (ENH-038) so renderers blit on scroll and redraw only changed rows. Python per-cell colors follow the palette and OSC 10/11 defaults too (ARC-101), and the deprecated bridges are gone (poll_events_legacy, Grid::erase_rectangle). par-mux gains held-dead panes that survive a daemon restart (ARC-114), list-commands discovery with held-state replay on registration (ENH-037), pane-exited-replay, clear-history, and opt-in per-pane hook-only endpoints (ENH-039). Feature flags split (mux-bin, macro-yaml), Cargo.lock is committed and release builds are --locked (ARC-107), core diagnostics reach the log facade (ARC-111), the streaming server is load-hardened (QA-184/191/192/198), and a large audit batch lands security and robustness fixes (SEC-125–SEC-134). See CHANGELOG.md for complete release notes.

Version 0.57.0 is a minor release focused on par-mux layout and lifecycle: panes can be zoomed (resize-pane -Z), reorganized with break-pane/join-pane/move-window/swap-window, and a pane whose child exits is now held with its exit code (remain-on-exit) and brought back with respawn-pane; split-window -b places a new pane before its target, and pane-info replies gain an optional trailing cmd=<base64> foreground-command token. The shared key encoder covers modifyOtherKeys and the macOS option-key modes (ENH-028; new Terminal.encode_key Python binding and FFI terminal_encode_key_ex), the stub generator emits real constructor signatures (ENH-030), FFI dirty-range readback is allocation-free (ENH-026), and par-mux telemetry is validated by a typed TelemetryV1 schema that rejects future-dated samples (ENH-029, QA-156). See CHANGELOG.md for complete release notes.

Version 0.56.0 is a minor release with Rust-embedder breaking changes: the 29 deprecated Terminal macro/trigger forwarders are removed on the 0.54.0 schedule (use terminal::MacroEngine/TriggerEngine; the Python API is unchanged), TermKeyEvent.key is now a plain u16 validated via TermKey::from_raw (an invalid discriminant is Unknown, not UB), and KittyParser::get_data returns Result. Headline additions: the C FFI on-device embedding surface (terminal_feed/terminal_dirty_ranges/pinned-buffer row readback/terminal_encode_key, with a cbindgen-generated, drift-gated terminal_core.h and make xcframework for iOS), per-consumer damage generations (Python damage_generation()/dirty_rows_since(); FFI ABI v2), par-mux rename-session/kill-session, and triggers that observe written text rather than render damage. Security: the par-mux host probe never runs repo-configured code (SEC-115), the Kitty path is bounded end to end against decompression bombs (SEC-116), and FFI string lengths always equal strlen (SEC-117). See CHANGELOG.md for complete release notes.

Version 0.55.0 is a minor release whose headline is the scheduled removal of the deprecated Terminal screenshot/benchmark forwarders (Rust embedders only): Terminal::screenshot/screenshot_to_file and Terminal::benchmark_rendering/benchmark_parsing/benchmark_grid_ops/run_benchmark_suite are gone, as promised by 0.54.0's deprecation schedule — use the crate::screenshot::render_terminal/save_terminal free functions and terminal::TerminalBenchmarks. The Python API surface is unchanged. Also ships the par-mux agent-telemetry enabler: a pane.report_agent_telemetry hook endpoint, telemetry served on list-agents rows with the %agent-telemetry-changed broadcast, and a host telemetry probe (disk-free percent and git state per pane cwd) swept by the daemon itself. See CHANGELOG.md for complete release notes.

Every other release is documented in CHANGELOG.md.

Features

Core Terminal Emulation

• VT100/VT220/VT320/VT420/VT520 Support - Comprehensive terminal emulation matching iTerm2
• Rich Color Support - 16 ANSI colors, 256-color palette, 24-bit RGB (true color)
• Text Attributes - Bold, italic, underline (5 styles), strikethrough, blink, reverse, dim, hidden
• Advanced Cursor Control - Full VT cursor movement and positioning
• Line/Character Editing - VT220 insert/delete operations
• Rectangle Operations - VT420 fill/copy/erase/modify rectangular regions (DECFRA, DECCRA, etc.)
• Scrolling Regions - DECSTBM for restricted scrolling areas
• Tab Stops - Configurable tab stops (HTS, TBC, CHT, CBT)
• Unicode Support - Full Unicode including complex emoji sequences and grapheme clusters
  • Variation selectors (emoji vs text presentation)
  • Skin tone modifiers (Fitzpatrick scale U+1F3FB-U+1F3FF)
  • Zero Width Joiner (ZWJ) sequences for multi-emoji glyphs
  • Regional indicators for flag emoji
  • Combining characters and diacritical marks

Modern Features

• Alternate Screen Buffer - Full support with automatic cleanup
• Mouse Support - Multiple tracking modes and encodings (X10, Normal, Button, Any, SGR, URXVT)
• Bracketed Paste Mode - Safe paste handling
• Focus Tracking - Focus in/out events
• OSC 8 Hyperlinks - Clickable URLs in terminal (full TUI support)
• OSC 52 Clipboard - Copy/paste over SSH without X11
• OSC 9/777/99 Notifications - Desktop-style alerts and notifications, including Kitty's OSC 99 protocol (chunked payloads, urgency levels, actions) via take_notifications_detailed()
• Terminal Capability Queries - XTGETTCAP (DCS + q) capability lookup and DECRQSS (DCS $ q) SGR/cursor-style/scroll-margin introspection
• Expanded XTWINOPS Reporting - CSI 11/13/19 t report window state, position, and screen size in characters
• Shell Integration - OSC 133 (iTerm2/VSCode compatible), OSC 1337 RemoteHost for remote host detection
• Semantic Buffer Zones - OSC 133 FinalTerm markers partition scrollback into prompt, command, and output zones
• Command Output Capture - Extract text from specific command execution blocks via get_command_output() and get_command_outputs()
• Semantic Snapshot API - Structured terminal state extraction via get_semantic_snapshot() for AI/LLM consumption, with configurable scope (visible, recent, full) and JSON output
• Kitty Keyboard Protocol - Progressive keyboard enhancement with auto-reset on alternate screen exit
• Synchronized Updates (DEC 2026) - Flicker-free rendering
• Tmux Control Protocol - Control mode integration support
• Observer API - Push-based event delivery with sync callbacks and async queues; convenience wrappers for common patterns (bell, title, CWD, command completion, zone changes)
• General-purpose File Transfer - OSC 1337 File= with inline=0 for host-to-terminal downloads, RequestUpload for terminal-to-host uploads, with progress tracking and lifecycle events
• Instant Replay - Cell-level terminal snapshots with input-stream delta recording, size-based eviction, and timeline navigation via SnapshotManager and ReplaySession
• C-Compatible FFI - embedding API in include/terminal_core.h (ptec_terminal_create/feed/dirty_ranges/read_row render loop, key encoding, snapshots, observers; SharedState/SharedCell) for C/C++ and Swift apps — see the FFI Guide and make xcframework for iOS

Graphics Support

• Sixel Graphics - DEC VT340 compatible bitmap graphics with half-block rendering
• iTerm2 Inline Images - OSC 1337 protocol for PNG, JPEG, GIF images
• Kitty Graphics Protocol - APC G protocol with image reuse, animations, zlib compression (o=z), and advanced placement; the t=f/t=t file media is security-gated (set_allow_file_media, default allows only spec-named *tty-graphics-protocol* temp files, deleted only after decoding)
• Unicode Placeholders - Virtual placements insert U+10EEEE characters for inline image display
• Unified Graphics Store - Protocol-agnostic storage with scrollback support
• Animation Support - Frame-based animations with timing and composition control
• Resource Management - Configurable memory limits and graphics dropped tracking

PTY Support

• Interactive Shell Sessions - Spawn and control shell processes
• Bidirectional I/O - Send input and receive output
• Process Management - Start, stop, and monitor child processes
• Dynamic Resizing - Resize with SIGWINCH signal
• Environment Control - Custom environment variables and working directory
• Event Loop Integration - Non-blocking update detection
• Cross-Platform - Linux, macOS, and Windows via portable-pty

Terminal Streaming (WebSocket)

• Standalone Server - Pure Rust streaming server binary (no Python required)
• Real-time Streaming - Sub-100ms latency terminal streaming over WebSocket
• Multiple Clients - Support for concurrent viewers per session
• Authentication - Optional API key authentication (header or URL param)
• Configurable Themes - Multiple built-in color themes (iTerm2, Monokai, Dracula, Solarized)
• Auto-resize - Client-initiated terminal resizing with SIGWINCH support
• Browser Compatible - Works with any WebSocket client (xterm.js recommended)
• Modern Web Frontend - Next.js/React application with Tailwind CSS v4 and xterm.js

Terminal Multiplexer (par-mux)

• tmux Control Mode - Sessions, windows, and split panes served over a local socket, attachable by tmux control-mode clients
• Real-Time Push - Pane output streams to clients as bytes arrive; no polling
• Agent Awareness - Panes report agent state over the same socket (JSON hook reports), with a scrape fallback for agents without hooks and an agent roster query
• Session Resume - Agent session identity persists across daemon restarts; agent panes respawn through their resume invocations
• Crash-Safe State - Atomic saves with quarantine of unreadable state files; a clean SIGTERM never loses the last window

Screenshots and Export

• Multiple Formats - PNG, JPEG, BMP, SVG (vector); HTML via export_html()
• Embedded Font - JetBrains Mono bundled - no installation required
• Programming Ligatures - =>, !=, >=, and other code ligatures
• True Font Rendering - High-quality antialiasing for raster formats
• Color Emoji Support - Full emoji rendering with automatic font fallback
• Session Recording - Record/replay sessions (asciicast v2, JSON)
• Export Functions - Plain text, ANSI styled, HTML export

Macro Recording and Playback

• YAML Format - Human-readable macro storage format
• Friendly Key Names - Intuitive key combinations (ctrl+shift+s, enter, f1, etc.)
• Keyboard Events - Record and replay keyboard input with precise timing
• Delays - Control timing between events
• Screenshot Triggers - Trigger screenshots during playback
• Playback Controls - Play, pause, resume, stop, and speed control
• Macro Library - Store and manage multiple macros
• Recording Conversion - Convert terminal recording sessions to macros

Utility Functions

• Text Extraction - Smart word/URL detection, selection boundaries, bracket matching
• Content Search - Find text with case-sensitive/insensitive matching
• Buffer Statistics - Memory usage, cell counts, graphics count and memory tracking
• Color Utilities - 18+ color manipulation functions (iTerm2-compatible)
  • NTSC brightness, contrast adjustment, WCAG accessibility checks
  • Color space conversions (RGB, HSL, Hex, ANSI 256)
  • Saturation/hue adjustment, color mixing

Documentation

• Quick Start Guide - Get running in minutes
• API Reference - Complete Python API documentation
• VT Sequences - Comprehensive ANSI/VT sequence reference
• Advanced Features - Detailed feature guides
• Architecture - Internal architecture details
• Security - PTY security best practices
• Building - Build instructions and requirements
• Configuration Reference - Configuration options
• Cross-Platform Notes - Platform-specific information
• VT Technical Reference - Detailed VT compatibility and implementation
• Fonts - Font configuration and rendering
• Macros - Macro recording and playback system
• Streaming - WebSocket terminal streaming
• Multiplexer - par-mux terminal multiplexer daemon
• Rust Usage - Using the library in pure Rust projects
• Observers - Push-based event delivery (callbacks and asyncio queues)
• Instant Replay - Cell-level snapshots and timeline navigation
• FFI Guide - C-compatible embedding API for Swift/JNI/C/C++
• Graphics Testing - Testing graphics protocol implementations
• Benchmarking - Criterion throughput benches and interleaved A/B comparison
• Testing Kitty Animations - Testing Kitty graphics animation support
• Regional Flag Limitation - Why regional-indicator flag emoji may not render as one glyph in some frontends
• Maturin Best Practices - Wheel build and packaging compliance review
• par-mux Design Pointer - Where the par-mux design plan lives
• par-mux Design Decisions - One-line summaries of the D-numbered decisions cited in code
• Documentation Style Guide - Standards for writing project documentation

Installation

From PyPI

uv add par-term-emu-core-rust
# or
pip install par-term-emu-core-rust

Wheels ship with the streaming server compiled in (StreamingServer works out of the box; check par_term_emu_core_rust._native.HAS_STREAMING to detect a build without it).

From Source

Requires Rust 1.98+ and Python 3.12+:

# Install maturin (build tool)
uv tool install maturin

# Build and install
maturin develop --release

Building a Wheel

# streaming is included: pyproject.toml [tool.maturin] features apply to every maturin build
maturin build --release
uv add --find-links target/wheels par-term-emu-core-rust
# or
pip install target/wheels/par_term_emu_core_rust-*.whl

Using as a Rust Library

The library can be used in pure Rust projects without Python. Choose your feature combination:

Note: Since v0.46.0 the pty_session module (real PTY backend) is a separate feature. Omit it only for headless use without PtySession. See docs/RUST_USAGE.md for details.

Download pre-built streaming server (recommended):

Pre-built binaries and web frontend packages are available from GitHub Releases:

# Download binary (Linux example)
wget https://github.com/paulrobello/par-term-emu-core-rust/releases/latest/download/par-term-streamer-linux-x86_64
chmod +x par-term-streamer-linux-x86_64

# Download web frontend (asset named par-term-web-frontend-v<version>.tar.gz from
# https://github.com/paulrobello/par-term-emu-core-rust/releases/latest)
mkdir -p ./web_term
tar -xzf par-term-web-frontend-v*.tar.gz -C ./web_term

# Run
./par-term-streamer-linux-x86_64 --web-root ./web_term

Available binaries: Linux (x86_64, ARM64), macOS (Intel, Apple Silicon), Windows (x86_64)

Or install from crates.io:

# Streaming server (no-default-features is required: the default python feature
# links libpython and fails at link time for a standalone binary)
cargo install par-term-emu-core-rust --no-default-features --features streaming-bin --bin par-term-streamer

# Terminal multiplexer daemon + client
cargo install par-term-emu-core-rust --no-default-features --features mux-bin --bin par-mux

Or build from source:

cargo build --bin par-term-streamer --no-default-features --features streaming-bin --release
./target/release/par-term-streamer --help

See docs/RUST_USAGE.md for detailed Rust API documentation and examples.

Embedding in iOS Apps

The core ships a C API (src/ffi.rs, header include/terminal_core.h) for on-device embedding — the same emulator as par-term, packaged as a static xcframework for iOS device and simulator:

# Requires Xcode + rustup target add aarch64-apple-ios aarch64-apple-ios-sim
make xcframework
# → target/xcframework/TerminalCore.xcframework

TerminalCore.xcframework (device + simulator slices) is attached to GitHub releases from 0.56.0 on; build it locally with make xcframework for unreleased commits. Each slice carries a Modules/module.modulemap, so after adding the xcframework to an Xcode project a Swift file just does import TerminalCore (the C header is re-exported; no bridging header needed).

The C surface is a full embedding API, not just snapshots (contracts and examples in the FFI Guide):

• Version check: ptec_terminal_abi_version — compare against the header's TERM_CORE_ABI_VERSION at startup
• Lifecycle/input: ptec_terminal_create / ptec_terminal_free / ptec_terminal_feed (VT bytes) / ptec_terminal_resize
• Damage: ptec_terminal_dirty_ranges returns coalesced inclusive dirty-row ranges and ptec_terminal_mark_clean consumes them; independent renderers use ptec_terminal_damage_generation + ptec_terminal_dirty_ranges_since, so one consumer never hides damage from another
• Scroll-aware damage (ABI v5): ptec_terminal_scroll_delta_since + ptec_terminal_content_dirty_ranges_since report a region's net scroll plus only the content-changed rows, so a renderer blits on scroll and redraws just the new rows
• Pinned readback: ptec_terminal_read_row / ptec_terminal_read_scrollback_row / ptec_terminal_scrollback_count copy cells into caller-owned buffers — no allocation, no full-grid copy per frame — with palette-resolved colors and default-color bits (ABI v4); ptec_terminal_read_cell_grapheme returns a cell's full grapheme cluster; ptec_terminal_scrollback_total_scrolled pairs with the count to sync a mirrored scrollback window; ptec_terminal_get_cursor / ptec_terminal_get_modes carry per-frame state
• Key encoding: ptec_terminal_encode_key turns key events into PTY bytes (xterm legacy, kitty level-1 disambiguate, and modifyOtherKeys, honoring application cursor keys and the negotiated kitty flags); ptec_terminal_encode_key_ex adds per-side macOS Option-key modes through TermKeyOptions
• Snapshots and observers: ptec_terminal_get_state / ptec_terminal_free_state, ptec_terminal_add_observer / ptec_terminal_remove_observer; the on_event_v2 slot delivers structured TermEvents (a TERM_EVENT_* kind plus a JSON payload)

Optional Components

Terminfo Installation

For optimal terminal compatibility, install the par-term terminfo definition:

# Install for current user
./terminfo/install.sh

# Or install system-wide
sudo ./terminfo/install.sh --system

# Then use
export TERM=par-term
export COLORTERM=truecolor

See terminfo/README.md for details.

Shell Integration

Enhances terminal with semantic prompt markers, command status tracking, and smart selection:

cd shell_integration
./install.sh  # Auto-detects bash/zsh/fish

See shell_integration/README.md for details.

Quick Start

Basic Terminal Emulation

from par_term_emu_core_rust import Terminal

# Create terminal
term = Terminal(80, 24)

# Process ANSI sequences
term.process_str("Hello, \x1b[31mWorld\x1b[0m!\n")
term.process_str("\x1b[1;32mBold green text\x1b[0m\n")

# Get content and cursor position
print(term.content())
col, row = term.cursor_position()
print(f"Cursor at: ({col}, {row})")

PTY (Interactive Shell)

from par_term_emu_core_rust import PtyTerminal

# Create PTY terminal and spawn shell
with PtyTerminal(80, 24) as term:
    term.spawn_shell()

    # Send commands
    term.write_str("echo 'Hello from shell!'\n")
    # Block until the output actually lands — no sleep guessing
    term.wait_for_text("Hello from shell!", timeout=3.0)

    # Get output
    print(term.content())

    # Resize terminal
    term.resize(100, 30)

    # Exit shell
    term.write_str("exit\n")
# Automatic cleanup

Environment Variables and Working Directory

Pass environment variables and working directory directly to spawn_shell() without modifying the parent process environment. This is safe for multi-threaded applications (e.g., Tokio):

from par_term_emu_core_rust import PtyTerminal

# Spawn with custom environment variables
with PtyTerminal(80, 24) as term:
    term.spawn_shell(env={"MY_VAR": "hello", "DEBUG": "1"})
    term.write_str("echo $MY_VAR\n")  # Outputs: hello

# Spawn with custom working directory
with PtyTerminal(80, 24) as term:
    term.spawn_shell(cwd="/tmp")
    term.write_str("pwd\n")  # Outputs: /tmp

# Combine both
with PtyTerminal(80, 24) as term:
    term.spawn_shell(env={"PROJECT": "myapp"}, cwd="/home/user/projects")

The spawn() method also accepts env and cwd parameters:

term.spawn("/bin/bash", ["-c", "echo $MY_VAR"], env={"MY_VAR": "test"}, cwd="/tmp")

Screenshots

term = Terminal(80, 24)
term.process_str("\x1b[1;31mHello, World!\x1b[0m\n")

# Save screenshot
term.screenshot_to_file("output.png")
term.screenshot_to_file("output.svg", format="svg")  # Vector graphics!
open("output.html", "w").write(term.export_html(include_styles=True))  # Styled HTML

# Custom configuration
term.screenshot_to_file(
    "output.png",
    font_size=16.0,
    padding=20,
    include_scrollback=True,
    minimum_contrast=0.5,  # iTerm2-compatible contrast adjustment
)

Color Utilities

from par_term_emu_core_rust import (
    perceived_brightness_rgb,
    adjust_contrast_rgb,
    contrast_ratio,
    meets_wcag_aa,
    rgb_to_hex,
    hex_to_rgb,
    mix_colors,
)

# iTerm2-compatible contrast adjustment
adjusted = adjust_contrast_rgb((64, 64, 64), (0, 0, 0), 0.5)

# WCAG accessibility checks
ratio = contrast_ratio((0, 0, 0), (255, 255, 255))
print(f"Contrast ratio: {ratio:.1f}:1")
print(f"Meets WCAG AA: {meets_wcag_aa((0, 0, 0), (255, 255, 255))}")

# Color conversions
hex_color = rgb_to_hex((255, 128, 64))  # "#FF8040"
rgb = hex_to_rgb("#FF8040")  # (255, 128, 64)
mixed = mix_colors((255, 0, 0), (0, 0, 255), 0.5)  # Purple

Macro Recording and Playback

from par_term_emu_core_rust import Macro, PtyTerminal
import time

# Create a macro manually
macro = Macro("git_status")
macro.set_description("Check git status and show branch")
macro.add_key("g")
macro.add_key("i")
macro.add_key("t")
macro.add_key("space")
macro.add_key("s")
macro.add_key("t")
macro.add_key("a")
macro.add_key("t")
macro.add_key("u")
macro.add_key("s")
macro.add_key("enter")
macro.add_delay(500)  # Wait 500ms
macro.add_screenshot("git_status.png")  # Trigger screenshot

# Save to YAML
macro.save_yaml("git_status.yaml")

# Load and play back
term = PtyTerminal(80, 24)
term.spawn_shell()

# Load macro from file
loaded_macro = Macro.load_yaml("git_status.yaml")
term.load_macro("git_check", loaded_macro)

# Play the macro
term.play_macro("git_check", speed=1.0)  # Normal speed

# Tick to execute macro events
while term.is_macro_playing():
    if term.tick_macro():  # Returns True if event was processed
        time.sleep(0.01)  # Small delay for visual effect

    # Check for screenshot triggers
    triggers = term.get_macro_screenshot_triggers()
    for label in triggers:
        term.screenshot_to_file(label)

# Convert a recording to a macro
term.start_recording("test session")
term.write_str("ls -la\n")
time.sleep(0.5)
session = term.stop_recording()

# Convert and save
macro = term.recording_to_macro(session, "ls_command")
macro.save_yaml("ls_command.yaml")

Examples

See the examples/ directory for comprehensive examples:

Basic Examples

• basic_usage_improved.py - Enhanced basic usage
• colors_demo.py - Color support
• cursor_movement.py - Cursor control
• text_attributes.py - Text styling
• unicode_emoji.py - Unicode/emoji support
• scrollback_demo.py - Scrollback buffer usage

Advanced Features

• alt_screen.py - Alternate screen buffer
• mouse_tracking.py - Mouse events
• bracketed_paste.py - Bracketed paste
• synchronized_updates.py - Flicker-free rendering
• shell_integration.py - OSC 133 integration
• test_osc52_clipboard.py - SSH clipboard
• test_kitty_keyboard.py - Kitty keyboard protocol
• hyperlink_demo.py - Clickable URLs
• notifications.py - Desktop notifications
• rectangle_operations.py - VT420 rectangle ops

Graphics and Export

• display_image_sixel.py - Sixel graphics
• test_sixel_simple.py - Simple sixel examples
• test_sixel_display.py - Advanced sixel display
• screenshot_demo.py - Screenshot features
• feature_showcase.py - Comprehensive TUI showcase

PTY Examples

• pty_basic.py - Basic PTY usage
• pty_shell.py - Interactive shells
• pty_resize.py - Dynamic resizing
• pty_event_loop.py - Event loop integration
• pty_mouse_events.py - Mouse in PTY
• pty_custom_env.py - Custom environment variables
• pty_multiple.py - Multiple PTY sessions
• pty_with_par_term.py - Integration with par-term

Terminal Streaming

• streaming_demo.py - Python WebSocket streaming server
• streaming_client.html - Browser-based terminal client

Macros and Automation

• demo.yaml - Example macro definition

Standalone Rust Server:

# Build and run (default: ws://127.0.0.1:8099)
make streamer-run

# Run with authentication
make streamer-run-auth

# Or use cargo directly
cargo build --bin par-term-streamer --no-default-features --features streaming-bin --release
./target/release/par-term-streamer --port 8099 --theme dracula

# With authentication
./target/release/par-term-streamer --api-key my-secret --theme monokai

# With system resource stats (CPU, memory, disk, network)
./target/release/par-term-streamer --enable-system-stats --system-stats-interval 5

# Install globally
make streamer-install
par-term-streamer --help

Available Themes: iterm2-dark, monokai, dracula, solarized-dark

Diagnostics and Test Scripts

• bce_scroll_test.py - Background color erase (BCE) during scrolling
• char_test.py - Character-specific rendering test
• gradient_test.py - Minimal gradient test for terminal wrap behavior
• rich_mimic_test.py - Rich-style output rendering test
• scroll_timing_test.py - Scroll timing test
• streaming_debug.py - Streaming server debug tool
• test_tui_clipboard.py - TUI clipboard and selection features
• test_underline_styles.py - Underline styles (SGR 4:x)
• render_utils.py - Rendering helpers imported by the other examples (not run directly)

Web Terminal Frontend

Using Pre-built Package (Recommended):

Download the pre-built static web frontend from GitHub Releases:

# Download and extract (asset named par-term-web-frontend-v<version>.tar.gz from
# https://github.com/paulrobello/par-term-emu-core-rust/releases/latest)
mkdir -p ./web_term
tar -xzf par-term-web-frontend-v*.tar.gz -C ./web_term

# Run streamer with web frontend
par-term-streamer --web-root ./web_term
# Open browser to http://localhost:8099

See web-terminal-frontend/README.md for detailed usage instructions.

Building from Source:

A modern Next.js-based web terminal frontend source is in web-terminal-frontend/:

# Install dependencies (bun)
make web-install

# Development server on http://localhost:3000
make web-dev

# Static build copied to web_term/ for par-term-streamer --web-root
make web-build-static

Features:

• Modern UI with Tailwind CSS v4
• xterm.js terminal emulator
• WebSocket connection to streaming server
• Theme selection and synchronization
• Responsive design
• Terminal resize support
• Customizable UI theme - Edit theme.css after build (no rebuild required)

See web-terminal-frontend/README.md for detailed setup and configuration.

TUI Demo Application

A full-featured TUI (Text User Interface) application is available in the sister project par-term-emu-tui-rust.

Installation: uv add par-term-emu-tui-rust or pip install par-term-emu-tui-rust

GitHub: https://github.com/paulrobello/par-term-emu-tui-rust

Technology

• Rust (1.98+) - Core library implementation
• Python (3.12+) - Python bindings
• PyO3 - Zero-cost Python/Rust bindings
• VTE - ANSI sequence parsing
• portable-pty - Cross-platform PTY support

Running Tests

# All tests: Rust, Rust streaming, and Python (rebuilds the extension first)
make test

# Rust tests only (plain `cargo test` fails to link under the default `python` feature)
make test-rust

# Python tests only (runs `make dev` first)
make test-python

Performance

• Zero-copy operations where possible
• Efficient grid representation
• Fast ANSI parsing with VTE crate
• Minimal Python/Rust boundary crossings

See docs/ARCHITECTURE.md for implementation details.

Security

When using PTY functionality, follow security best practices to prevent command injection and other vulnerabilities.

See docs/SECURITY.md for comprehensive security guidelines.

Contributing

Contributions are welcome! Please submit issues or pull requests on GitHub.

Development Setup

git clone https://github.com/paulrobello/par-term-emu-core-rust.git
cd par-term-emu-core-rust
make setup-venv  # Create virtual environment
make pre-commit-install  # Install pre-commit hooks (recommended)
make dev  # Build library
make checkall  # Run all quality checks

Code Quality

All contributions must pass:

• Rust formatting (cargo fmt)
• Rust linting (cargo clippy)
• Python formatting (make fmt-python)
• Python linting (make lint-python)
• Type checking (pyright)
• Tests (make test-python)

TIP: Use make pre-commit-install to automate all checks on every commit!

See CONTRIBUTING.md for the contribution workflow, and CLAUDE.md for detailed development instructions.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Author

Paul Robello - probello@gmail.com

Links

• PyPI: https://pypi.org/project/par-term-emu-core-rust/
• Crates.io: https://crates.io/crates/par-term-emu-core-rust
• GitHub: https://github.com/paulrobello/par-term-emu-core-rust
• TUI Application: https://github.com/paulrobello/par-term-emu-tui-rust
• Documentation: See docs/ directory
• Examples: See examples/ directory