From Ghost to Zulip: Setting Up Zulip Locally on WSL2 (and Fixing Tricky Python Issues)

Source: Dev.to

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Introduction

After contributing to Ghost, I wanted to push myself further by working on a larger and more complex backend system.

That curiosity led me to Zulip, an open‑source team collaboration tool known for its topic‑based threading and production‑grade architecture.

Zulip is built with:

• Django
• Tornado
• PostgreSQL
• RabbitMQ

Setting up Zulip locally isn’t hard, but it’s very different from a typical Django project. I ran into a few unexpected issues, especially around Python virtual environments and WSL configuration.

In this post, I’ll walk through:

• How I set up Zulip locally on WSL2
• The issues I faced during setup
• How I fixed them, including the activate_this.py problem

If you’re new to Zulip or moving into larger backend systems, this guide should help you avoid common setup blockers.

Who This Post Is For

• Developers contributing to Zulip for the first time
• Open‑source contributors moving beyond small projects
• Anyone using WSL2 on Windows
• Developers stuck with Python 3.12 or activate_this.py errors

Prerequisites

General

• 2 GB+ RAM
• Stable internet connection
• GitHub account

Windows

• Windows 10/11 (64‑bit)
• Virtualisation enabled (VT‑x / AMD‑V)
• Admin access

Git and GitHub Setup

If Git is already configured, you can skip this section.

1. Generate an SSH key

   ssh-keygen -t ed25519 -C "your_email@example.com"

2. Copy the public key

   cat ~/.ssh/id_ed25519.pub

3. Add it to GitHub → Settings → SSH and GPG Keys.

Setting Up WSL2 for Zulip

If you already use native Ubuntu or WSL2, feel free to skip ahead.

Enable Virtualisation

Make sure VT‑x / AMD‑V is enabled in BIOS.

Install WSL2

wsl --install

This installs Ubuntu automatically.

Enable systemd (Required)

Zulip relies on background services like PostgreSQL, Redis, and RabbitMQ.

sudo nano /etc/wsl.conf

Add the following:

[boot]
systemd=true

Restart WSL:

wsl --shutdown

Install Required Services

sudo apt update && sudo apt upgrade

sudo apt install rabbitmq-server memcached redis-server postgresql

RabbitMQ Configuration

sudo nano /etc/rabbitmq/rabbitmq-env.conf

Add:

NODE_IP_ADDRESS=127.0.0.1
NODE_PORT=5672

Cloning the Zulip Repository

1. Fork Zulip on GitHub, then clone your fork:

   git clone --config pull.rebase git@github.com:YOURUSERNAME/zulip.git
   cd zulip
   git remote add -f upstream https://github.com/zulip/zulip.git

Running Zulip Locally

1. Install dependencies

   ./tools/provision

2. Activate the virtual environment

   source .venv/bin/activate

3. Start the dev server

   ./tools/run-dev

4. Visit

   http://localhost:9991

Common Issues I Faced (and How I Fixed Them)

Issue 1: Missing activate_this.py

Error

FileNotFoundError: No such file or directory ... activate_this.py

Why this happens

Zulip now uses uv, which doesn’t automatically create activate_this.py. Some scripts still expect it.

Fix

Manually create the file:

cat > .venv/bin/activate_this.py   
- Zulip Dev Docs:   
- Zulip Community Chat:   
- WSL Docs:   
- uv: