# About insomnilog
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`insomnilog` is an asynchronous Rust logging library designed for real-time and
latency-sensitive applications. All logging on the hot path is **zero-allocation**
and **lock-free** — log records are serialised as raw bytes into a per-thread
ring buffer and decoded by a background worker thread.
## Design goals
- **Real-time safe hot path.** The logging macros never allocate heap memory,
never acquire a lock, and never block. They perform a level check, encode
arguments directly into a pre-allocated ring buffer, and return.
- **Asynchronous by default.** Formatting, sink dispatch, and I/O happen on a
dedicated backend worker thread. The calling thread pays only the cost of the
ring-buffer write.
- **Explicit configuration, no global magic.** You start the backend once with
`insomnilog::start(opts)`, create named loggers and sinks explicitly, and pass
a logger reference to each call site. There is no implicit global logger, no
auto-start, and no hidden process-exit hook.
- **Composable sinks.** A `Sink` receives a decoded `LogRecord` and decides its
own output format. One sink can write human-readable text, another can write
structured JSON, a third can forward to a metrics system — all from the same
logger.
## Inspiration
`insomnilog` is heavily inspired by [Quill](https://github.com/odygrd/quill),
a C++ low-latency logging library with similar goals: asynchronous background
processing, per-thread lock-free queues, and a hot path that does as little
as possible.
