Seems like development has halted? Curious to know if it's still being worked on...
Not halted by any means. It currently relies on Litestream to do streaming replication, but unfortunately the author of Litestream removed streaming replication. I have been working on a Rust rewrite of Litestream which will be ready within a few weeks and will be incorporated into Covert. My focus on the Litestream rewrite is the reason there hasn't been any commits directly to the Covert repo the last months.
Litestream author here. The streaming replication was moved to a different project called LiteFS[1]. That may be a fit for you or, at the very least, it could be a helpful reference for your Rust port.