automerge-rs VS redb

See also, Autosurgeon (with a 0.3.0 release today), which is a higher level API on top of Automerge for Rust:

I'm building a mobile app with a server backend, and I was looking for resources to build them in an offline-first way (since unlike on the browser, people expect to use apps offline, if they can, such as fitness or habit trackers).

I found the concept of conflict-free relational data types (CRDTS) interesting as it allows you to have fully offline experiences while also having a conflict-free syncing experience. I was looking for some good libraries and came across automerge [0] and yrs [1], but both had some rough APIs as they're primarily low-level Rust libraries that are wrapped by higher-level TypeScript APIs.

Autosurgeon wraps the low-level API of automerge to make it much more ergonomic, closer to the TypeScript experience, but in Rust of course. You can for example use `struct`s which autosurgeon will serialize and deserialize automatically, which is not present in base automerge, which focuses more on string keys and arbitrary values.

I am planning on using this together with Flutter and flutter_rust_bridge [2] in order to use this same Rust library everywhere. In this case, the server just becomes another (albeit more privileged) client.

[0] https://github.com/automerge/automerge-rs

[1] https://github.com/y-crdt/y-crdt

[2] https://github.com/fzyzcjy/flutter_rust_bridge

I found the concept of conflict-free relational data types (CRDTS) interesting as it allows you to have fully offline experiences while also having a conflict-free syncing experience. I was looking for some good libraries and came across automerge and yrs, but both had some rough APIs as they're primarily low-level libraries that are wrapped by TypeScript APIs.

Yes, the plan is to use PostgreSQL. I had a discussion with one of the devs in this ticket about the strategy for this.

In any case, my current plan is to use Automerge for the data handling itself (so I can easily do collaboration), but that crate doesn't handle on-disk storage. For this I need another solution, and a K/V store is well suited for this task.

15 years working in software, Rust has been my favourite language for the last 2. Recently completed a contract to prototype a distributed Tailscale-inspired VPN built on Ink and Switch's CRDT project automerge-rs.

Complex topic. There's a very easy-to-use CRDT library for Rust (automerge), while there isn't much support for operational transforms (although Aper is new to me, I have to check it out).

I've been watching automerge-rs like a hawk, because they seem to be the only CRDT implementation where you don't need a Mathematics master to understand how to use it. They've been working on a rewrite for the last two years, hopefully they'll do a new release soon.

https://github.com/automerge/automerge-rs

By the way despite that particular repo (@localfirst/state) last being touched 6 months ago, Herb Caudill definitely seems still active in this space (I believe he's been working on other parts of this more recently -- e.g. ideas about authentication), and I think automerge development itself is quite active right now leading up to a 1.0 release which seems fairly imminent, for which a lot of fundamental work has been done, also coordinating with automerge-rs.

I wrote redb (https://github.com/cberner/redb) using mmap, initially. However, I later removed it and switched to read()/write() with my own user space cache. I'm sure it's not as good as the OS page cache, but the difference was only 1.2-1.5x performance on the benchmarks I cared about, and the cache is less than 500 lines of code.

exposure of the redb builder functionalities.

redb has reached its 1.0 release. The file format is now gauranteed to be backward compatible, and the API is stable. I've run pretty extensive fuzz testing, but please report any bugs you encounter.

I'm just now updating the benchmarks in the readme with multi-threaded workloads :) https://github.com/cberner/redb/pull/576

redb, but that doesn't have a stable file format yet,

I also have to support web, so I'm considering a hybrid approach with a direct IndexedDB API there and something like sqlite, percy, sanakirja, or redb on native.

Nice list, but don’t forget persy, redb and sanakirja too!

check out https://github.com/cberner/redb! it is inspired by LMDB and has comparable performance, but is entirely built in rust!

Yup, the language is immature in some domains like data replication, compilation time, lifetime expressivity, not having a default async runtime and the incompatibility of all of them. But many of these domains are worked on and improved every day this is why I love this language so much. This is because there is space for improvement. I also hope that one day we will have a pure-Rust LMDB alternative that I can contribute to without fear of C.

they are, ya! I'm quite excited about that, and already have a PR open to use GATs. It's not enough to fix this issue though, because std needs to add support for LendingIterator too