Getting Started

This guide walks through setting up reeln from scratch on a fresh machine. All commands work on macOS, Linux, and Windows.

1. Open a terminal

Platform

How

macOS

Spotlight (Cmd+Space) → type “Terminal” → Enter

Windows

Start menu → “Terminal” or “PowerShell”

Linux

Ctrl+Alt+T (most distros) or find “Terminal” in your app launcher

2. Check Python

reeln requires Python 3.11 or later.

python3 --version

If you see 3.11.x or higher, you’re good — skip to step 3.

Install or upgrade Python

Option A — Official installer (all platforms):

Download from python.org/downloads and run the installer. Make sure “Add Python to PATH” is checked on Windows.

Option B — Package manager:

# macOS (Homebrew)
brew install python@3.13

# Ubuntu / Debian
sudo apt update && sudo apt install python3.13

# Windows (winget)
winget install Python.Python.3.13

Option C — pyenv (manage multiple versions):

# Install pyenv (macOS/Linux)
curl https://pyenv.run | bash

# Install Python
pyenv install 3.13
pyenv global 3.13

After installing, verify:

python3 --version
# Python 3.13.x

3. Install ffmpeg

reeln uses ffmpeg for all video processing. You need version 5.0 or later with these capabilities:

  • libx264 — H.264 video encoding

  • aac — audio encoding

  • libass — subtitle/overlay rendering

Most standard ffmpeg packages include all of these.

# macOS
brew install ffmpeg

# Ubuntu / Debian
sudo apt install ffmpeg

# Windows
winget install ffmpeg
# or: choco install ffmpeg

Verify your install:

ffmpeg -version

Look for the version number in the first line — it should be 5.x or higher.

4. Install reeln

With pip

pip install reeln

Verify

reeln --version

This prints the reeln version and detected ffmpeg info.

5. Run health checks

reeln doctor

doctor checks everything reeln needs to run:

  • ffmpeg discovery and version

  • Codec availability (libx264, aac, libass)

  • Hardware acceleration support

  • Config file validity

  • Directory permissions

  • Plugin health (if any are installed)

Each check reports PASS, WARN, or FAIL with actionable hints.

6. Set up shell completion (optional)

# zsh (default on macOS)
reeln --install-completion zsh

# bash
reeln --install-completion bash

# fish
reeln --install-completion fish

Restart your shell after installing completion.

Next steps