fastlogging-rs: High-Performance Logging for many different Programming Languages

Martin Bammer — Mon, 21 Sep 2026 20:18:36 +0000

Every log.info(...) call can block your hot path, serialize your threads, and slow down your I/O-bound workloads. That's why I created fastlogging-rs: a Rust-powered logging framework that is extremely fast, thread-safe, and available with a similar API in 8 different programming languages.

Release, 0.9.0, is available with the following features:

Initial release of the Rust core (fastlogging crate) with bindings for Python, C, C++, Go, Java (FFM and JNI) and C#
Non-blocking, asynchronous logging — writers run in background threads
Optional file rotation and compression
Optional AES encryption for network logging
Configuration via API or configuration file (JSON, XML, YAML)
Automatic forwarding of log messages from sub processes to the main process
Logging to OpenTelemetry

Because speed matters…

Compared to Python’s built-in logging module:

Writing to a file is up to 147× faster
Rotating file logging is up to 207× faster
Even compared to Apache Log4j, fastlogging-rs is up to 9× faster

When your application logs millions of messages, these speedups can turn minutes into seconds.
fastlogging-rs is written in Rust and comes with thin wrappers for your favorite programming language. All bindings share a similar API, so you can use the same logging concepts across your whole stack:

Rust — fastlogging (native core)
Python — pyfastlogging (pyo3, >= 3.10)
C — cfastlogging (FFI, cbindgen header)
C++ — cxxfastlogging (type-safe cxx bridge)
C++ — cppfastlogging (C++17 RAII over the C ABI)
Go — gofastlogging (cgo wrapper)
Java — jfastlogging-ffm (Foreign Function & Memory API)
Java — jfastlogging-jni (Java Native Interface)
C# — csharpfastlogging (P/Invoke)

Logging calls are non-blocking: each call performs a cheap level check (a single integer comparison, no lock) and hands the message to a channel. A background LoggingThread drains that channel and dispatches to each writer's own thread. The speed of your writers never slows down your application - as long as the queue doesn't run full.

Thread-safe logging calls
Multiple writers (sinks) per logger: console, file, network, syslog, callback
Optional file rotation and compression
Optional AES encryption for network logging
Configuration via API or configuration file (JSON, XML, YAML)
Automatic forwarding of log messages from sub processes to the main process

Installation Rust / Python

cargo add fastlogging

pip install pyfastlogging

Usage example in Rust / Python

use fastlogging::{logging_new_default, LoggingError};

fn main() -> Result<(), LoggingError> {
    let mut log = logging_new_default()?;
    log.info("Hello, fastlogging!")?;
    log.shutdown(false)?;
    Ok(())
}

from fastlogging import Logging

log = Logging()
log.info("Hello, fastlogging!")
log.shutdown(False)

For more example see github link below.

For detailed benchmark data and methodology, see the benchmark documentation:

github

You can also explore the full benchmark results with interactive charts and tables:

benchmarks

If your application spends time logging, fastlogging-rs can provide substantial performance improvements with minimal code changes — in whichever language you happen to be writing.

The API is intentionally familiar, making migration from logging, log4j, or your current framework straightforward while unlocking significantly faster execution.

Source code, documentation, and issue tracker:

github

Licensed under the MIT or Apache-2.0 License.

DEV Community: Martin Bammer

fastlogging-rs: High-Performance Logging for many different Programming Languages

Installation Rust / Python

Usage example in Rust / Python