Show HN: Targeted Log Levels

Hey HN!

A bug has been reported. Maybe it’s the data pipeline for a particular customer, checkouts with Paypal in Australia or Bluetooth connections on older Android devices. Whatever the case is, you’re sitting there and there’s simply not enough information to diagnose the issue.

Wouldn’t it be great if you could snap your fingers and start looking at DEBUG logs for just the customer in question? We think so too. This was one of the most delightful features that the core platform teams provided me when I worked at a large org and I missed it dearly after I left.

Here's what Prefab provides so far:

1. Something failing? Instantly change log levels for any class or package. Not specific enough? Target specific users, transactions, or devices and only output debug logs for them. Keep your logging code and log aggregator as-is, we just adjust the levels. Very easy to install this locally and give it a try. Hopefully a huge boon to your MTTR. 2. A realtime, reliable Dynamic Configuration system that gives you interactive, real-time, fine-grained control over operations of your deployed systems.

The core technology is this dynamic configuration system, similar in behavior to Netflix's https://github.com/Netflix/archaius, Amplitude's DynConf https://amplitude.com/blog/dynamic-configuration or HubSpot's conspicuously well-named "Config" https://product.hubspot.com/blog/backend-tooling. Client libraries bootstrap off a CDN and then start an SSE connection to get updates.

We'd love for you to take Prefab for a spin and share your thoughts. Full support for these logging features in Java & Ruby today. Python/Node/Elixir are in alpha zone and we would love to work with you on their development. See it in action: https://youtu.be/8AsEJF-NwAQ

We're so excited to share what we've built. We started Prefab because we think there is too much great, general-purpose tech that's locked away in large orgs. Just because I no longer have a team of 50 developer platform engineers on my side, doesn’t mean I don't want the fruits of their labor.

If you've used dynamic configuration or dynamic log levels before I'd love if you would share your experiences and favorite use cases here.

- Jeff & Prefab