Setting Up Writebook on Coolify

Basecamp (37signals) recently released Writebook - a simple, self-hosted application for publishing books on the web. It’s a Rails app distributed as a Docker image, and I wanted to run it on my Coolify server. Should be straightforward, right? Well, almost.

What is Writebook?

Writebook lets you publish content in Markdown, with support for picture pages, chapters, and title pages. Books can be public or private, and everything is searchable. It’s a nice alternative to throwing your documentation into yet another wiki or Confluence instance.

The official install uses their ONCE installer, but since I’m already running Coolify for my other apps, I wanted to deploy it there instead.

The Setup

I created a new application in Coolify using the Docker image: ghcr.io/basecamp/writebook:latest

Mapped the domain to books.jace.pro, added a persistent volume at /rails/storage, and hit deploy. That’s when the fun started.

Gotcha #1: SSL Conflict

Writebook tries to handle SSL internally by default. Since Coolify uses Traefik at the edge to terminate SSL, this creates a conflict.

The fix: Add an environment variable:

DISABLE_SSL=true

This tells Writebook to serve plain HTTP on port 80 and let Traefik handle the certificates.

Gotcha #2: Missing SECRET_KEY_BASE

Rails apps need a secret key base for production. The container kept crashing with:

ArgumentError: Missing `secret_key_base` for 'production' environment

The fix: Generate a key and add it as an environment variable:

openssl rand -hex 64

Then add SECRET_KEY_BASE with that value to your Coolify environment variables.

Gotcha #3: Permission Denied on Storage

The container started but immediately crashed with:

Errno::EACCES: Permission denied @ dir_s_mkdir - /rails/storage/db

Coolify creates persistent storage directories as root, but Writebook runs as a non-root user (UID 1000). The Rails user couldn’t write to the storage volume.

The fix: SSH into your server and fix the ownership:

chown -R 1000:1000 /data/coolify/storage/books.jace.pro

After that, a quick restart and the app came right up.

The Result

Writebook is now running at books.jace.pro. It’s a clean, simple interface for publishing content - exactly what you’d expect from the Basecamp team.

Coolify + Self-Hosting

I’ve been running Coolify for a while now and it’s been solid. Having everything in one place - my blog, various side projects, and now Writebook - makes management easier. Sure, there are occasional hiccups like permission issues, but that’s just part of self-hosting.

The lesson here: always check your storage permissions, and remember that Docker containers often run as non-root users even when you’re deploying as root.

If you’re running Coolify and want to self-host your own book publishing platform, Writebook is worth a look. Just remember those three environment variables and the permission fix.