I've recently launched https://certobserver.com, a service for getting alerts before certificates expire. The goal is to be very easy to use with simple (pay-as-you-go, so no need to choose a plan) and affordable pricing.

The next step is to improve the landing site. I like the current no-frills design, but unfortunately I think I'm in the minority.

Feature-wise I'm planning to add support for getting alerts via Slack. I'd also like to make use of certificate transparency logs, alerts to start with but maybe for other stuff as well.

The stack is C#, .NET 10 and PostgreSQL 18 running on Hetzner VMs. I also self-host Forgejo and OpenSearch on Hetzner VMs. I recently switched from VS Code to JetBrains Rider and I think the latter is much better for C#. (I'm using Linux so Visual Studio is not an option for me.)