message-db VS txid-syncing

I’m addition to the alternatives mentioned, here’s another Postgres-only ES implementation: https://github.com/message-db/message-db

Thalo is a new Rust library that provides a runtime for WASM-based event sourcing. With Thalo, developers can compile their aggregates and components into WASM modules and use them in the runtime to handle commands and persist events to an event store. The library is built on top of Wasmtime and Message DB, and uses the ESDL schema language to define aggregates. While Thalo is not yet ready for real-world use, it has the potential to make event sourcing more accessible to a wider range of languages that compile to WASM, allowing for a language-agnostic runtime. Give it a try and let us know what you think! https://github.com/thalo-rs/thalo

Its built on top of Wasmtime for wasm execution, and MessageDb which is a message store for Postgres.

We are using message db which is uses postgres under the hood, and provides a few useful postgres functions. We use it with `postgres-simple` and have a small internal library. However my colleague is working on abstracting our logic and open sourcing into a library here: https://github.com/Disco-Dave/message-db

Check out MessageDB https://github.com/message-db/message-db. It's basically Postgres and can be installed into any Postgres DB.

Trying a new language or framework is fun experiments that you spend a few hours on. I have been enjoying implementing Message DB[0] in a hobby project. My current job is not in programming, and not looking for one.

[0]https://github.com/message-db/message-db

Nice job, eugene-khyst. Looks very comprehensive from an initial skim.

I've worked on something in the same space, with a focus on reliable but flexible synchronization to many consumers, where logical replication gets impractical.

I have a mind to do a proper writeup, but at least there is code at https://github.com/cognitedata/txid-syncing (MIT-licensed) and a presentation at https://vimeo.com/747697698

The README mentions …

> A long-running transaction in the same database will effectively "pause" all event handlers.

… as the approach is based on the xmin-horizon.

My linked code works with involving the MVCC snapshot's xip_list as well, to avoid this gotcha.

Also, note that when doing a logical restore of a database, you're working with different physical txids, which complicates recovery. (So my approach relies on offsetting the txid and making sure the offset is properly maintained)