Claude Project: Thermal Printer Guestbook

March 20, 2026

Overview

I’ve always admired people who release web toys for the anonymous public to play with. I’m also interested in bridging the gap between online spaces and real life. In some ways, I wish we could make online spaces more like real life without having to completely lose digital privacy. I made this guestbook to explore that concept. It was loosely inspired by the guestbook at Good Enough. All mentioned source code can be found on my github.

The Process

Setting up the Printer

I have a mini-PC on my desk that’s running 24/7. I’ve set up Claude on it and I can SSH to it from my phone. I figured that would be a good candidate to set up the thermal printer. First things first, was to plug it in and see if I can get something to print. Claude was great at helping me install the necessary driver, troubleshoot, and get me to a point where I could echo some text to a script and send it to the printer. Claude even suggested we set up a udev (a command I was unfamiliar with at the time) rule so that the printer auto-binds as soon as it’s plugged in.

One thing I learned is that thermal printers are operationally quite simple. It has a single button to open the paper refill tray. You just stick the paper roll in. No need to daintily thread it through some slot. It really feels like they are meant to be plug and play. A far cry from the software update ridden, subscription only, user account required technologies of today.

Planning with Claude

When I started this project, I gave Claude the requirements for the guestbook application:

• Store every message and when it was made.
• Have sensible rate limiting to prevent spam.
• Sanitize the input to prevent injection vulnerabilities.
• Allow me to review the prints before publishing to a gallery of my favorites.
• When reviewing, allow me to add commentary which will be displayed on the gallery.

It was fascinating to watch Claude come up with a plan. Because I already had a mental breakdown of the steps I needed, it was relatively easy to verify if Claude’s plan was sensible. Claude suggested the following:

• A SQLite database with an approved column to control what gets published.
• Appropriate API endpoints for the gallery and user submission.
• Sanitizing the input for printer control characters in the backend service.
• Parameterized queries to prevent SQL injection.
• A script that will query the DB and let me approve any messages one by one and add commentary (gallery approval workflow).
• A per-IP rate limit as well as a global rate limit and a character limit per message.
• Start the service with systemd so that it automatically recovers in case of reboot or crashes.

Setting up a printer server background service

The next step was to setup a small HTTP server that’s run as a systemd service. All it does is accept print jobs via an API request and send it to the thermal printer.

Building the frontend

It created simple HTML pages for the guestbook and gallery. This was in lieu of Claude’s suggestion of setting up a React app. React felt kind of heavy handed for this use case and I wanted it to be extremely barebones. Finally, we setup a DNS record and pointed it to the server and secured it with a Let’s Encrypt SSL certificate.

Final Thoughts

This was a really fun experience that I feel like I was only able to accomplish in a reasonable amount of time with AI assistance. The idea of troubleshooting printer drivers on a Linux machine sounds arduous and boring with little payoff. But Claude made it a relatively painless process. Setting up a simple web server and basic frontend is straightforward. However, knowing myself, I’d probably spend most of my time evaluating trade offs between tools or fighting configurations just to get things working. Claude took the friction away and turned this from a multi-weekend project into a single evening project. I feel like AI assistants are great at filling this niche.