Installation

Requirements

• Python 3.11+

• ffmpeg 5.0+ — reeln uses the ffmpeg binary for rendering video with complex filter chains, subtitle overlays (requires libass), and codec support (libx264, aac)

Install reeln

With pip

pip install reeln

With uv

uv tool install reeln

This installs the reeln CLI and reeln-native (a Rust extension that handles media probing, concatenation, frame extraction, and overlay rendering using ffmpeg libraries). Pre-built wheels are available for Linux (x86_64) and macOS (arm64) — other platforms build from source and require ffmpeg development headers.

Development install

git clone https://github.com/StreamnDad/reeln-cli.git
cd reeln-cli
make dev-install

This creates a virtual environment and installs reeln in editable mode with dev dependencies (pytest, ruff, mypy).

Install ffmpeg

reeln requires the ffmpeg binary (5.0 or later) with at least these capabilities:

• libx264 — h264 video encoding

• aac — audio encoding

• libass — ASS subtitle rendering (used for overlay templates)

Most standard ffmpeg packages include all of these. After installing, run reeln doctor to verify your setup.

macOS

brew install ffmpeg

Ubuntu / Debian

sudo apt install ffmpeg

Windows

winget install ffmpeg
# or
choco install ffmpeg

Verify

ffmpeg -version    # should show 5.0+
reeln doctor       # checks ffmpeg, codecs, config, permissions, plugins

Shell completion

reeln supports tab completion for bash, zsh, and fish:

# zsh
reeln --install-completion zsh

# bash
reeln --install-completion bash

# fish
reeln --install-completion fish