Timmerdorp webshop, 2025 update

Introduction

This is a follow up on the timmerdorp ticket shop post (opens new window), where I described the history of the yearly ticket sale and the issues we had. This year I want to share some of the improvements we made and how the sale went.

2025

Retry on kubernetes, some code improvements to prevent the issues from last year. I scaled up a little more aggresive than last year:

• added 2 8vcpu nodes to the cluster and scaled to 12 pods (6 parse and 6 nuxt) distributed over the 3 nodes
• added a dedicated redis (valkey) database
• scaled up the database to m80 (hosted on atlas)

This resulted in a more stable webshop, with no capacity related issues during the sale. There were however some small issues:

• The implemented ticket counter in redis worked mostly okay, but it seems some race conditions were still present, resulting in a few invalid available tickets during the release of expiring orders.
• The demand grew even further, 1200 users (whatever this exactly means, google analytics) tried to buy tickets at 10:00 am.