A simple fork of the slog-json 2.6.1 (original version by Dawid Ciężarkiewicz) crate which introduces a buffering and concurrency while generating output of a log record.
An original drain requires mutex before using. This fork introduces a buffering before final write and it uses a mutex only on same final write, making same logging as concurrent and parallel.
Original slog-json: https://crates.io/crates/slog-json, https://github.com/slog-rs/json.