Show HN: T4 – a versioned datastore with branching and time-travel (S3-backed)

[amakhov]

Hi HN,

I built t4, a datastore that stores its WAL and snapshots in S3.

Instead of traditional storage, it writes append-only segments to object storage and reconstructs state from checkpoints + WAL.

A side effect of this model is that the database becomes naturally versioned: you can restore any past state, branch from any point (with copy-on-write) and replay history

I started this as an experiment to replace etcd in Kubernetes, but it’s evolving into a general-purpose versioned state store.

Curious what people think about it and appreciate any feedback!

[vbond]

This is pretty cool, it would be totally awesome to also get Node.js / Python support.

[amakhov]

Thanks for the feedback! t4 supports etcd API, so basically any etcd client should work in a standalone setup, but yeah, I'm thinking about introducing custom clients for popular languages.