Why Holter exists
Monitor everything.
Hand over nothing.
Most monitoring tools ask you to bolt an agent into your stack, paste in cloud credentials, or wire up an SDK before they tell you a thing. Holter takes the opposite bet: the most important question — is it working right now? — can be answered from the outside, plus a heartbeat for the parts that cannot.
The gap we kept falling into
Finding out you are down from an angry customer is the worst way to find out. The status page is green, the dashboards look fine — and then the support tickets start. The cron that was supposed to run last night silently did not. The backup has not completed in a week. The certificate expires on a Saturday.
The tools that catch all of that tend to be heavy: install this, grant that, integrate the other. So the small stuff goes unwatched until it bites. We wanted something you could point at anything in three minutes — a URL, an endpoint, a cron, a queue — without handing over the crown jewels.
That is Holter. Watch your whole stack from one place, and keep it all at arm’s length.
What we believe
Observe from the outside
Holter watches your services the way your users reach them — from the public internet. We fetch your URLs, read your public DNS, check your certificates. No server agent, no SDK in your codebase, no access to your servers.
You push proof, we never reach in
For the things we cannot see from outside — crons, queues, backups — your jobs send us a heartbeat when they finish. You hand us a ping, not the keys. We never connect to your database, your cloud, or your repo.
The alert is the product
Nobody watches dashboards at 3am. The whole job is to be quiet when things are fine and loud when they are not — detect fast, tell the right person, and get out of the way.
Your data stays yours
We store what we observe and what you send us — nothing more. Staying out of your infrastructure means we hold far less sensitive data than a tool that plugs into your servers.
Who is behind it
Holter is built by a small, independent team that has been on the wrong end of enough 3am pages to care about getting this right. We are focused on one thing — telling you the truth about whether your stuff is up — and we would rather do that one thing well than become another sprawling observability suite.
Holter is built by Wonderful People ↗ — an independent studio that makes tools we want to use ourselves.
— The Holter team
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