For my system layer project, I need a fast, low-RAM-usage, flexible, extensible daemon that speaks the Syndicate network protocol and exposes dataspace and system management services to other processes.

So I built one in Rust.

git clone https://git.syndicate-lang.org/syndicate-lang/syndicate-rs

It uses the Syndicated Actor Model internally to structure its concurrent activities. The actor model implementation is split out into a crate of its own, syndicate, that can be used by other programs. There is also a crate of macros, syndicate-macros, that makes working with dataspace patterns over Preserves values a bit easier.¹

The syndicate crate is reasonably extensively documented. The server itself is documented here.

The implementation includes:

• Actor supervision, inspired by Erlang/OTP’s supervisors;

• Full support for a tree of nested facets within each actor, representing that actor’s conversational contexts;

• A generic implementation of point-to-point Syndicate network protocol, instantiated for plain TCP/IP, websockets, Unix domain sockets, and stdin/stdout;

• A gatekeeper that resolves long-lived, “sturdy” references like
  <ref "syndicate" [] #[acowDB2/oI+6aSEC3YIxGg==]>
  to on-the-wire usable object capability references;

• An inotify-based configuration watcher service that monitors a directory full of Preserves text files for changes;

• An interesting approach to internal flow control;

• and more!