# slog-rs/slog

Structured, contextual, extensible, composable logging for Rust

Repository: https://github.com/slog-rs/slog
Canonical: https://ross.abutalabs.com/products/slog
Homepage: https://slog.rs/
Language: Rust
License: Apache-2.0
License Family: permissive
Topics: rust, logging, logging-library, structured-logging, hierarchical-loggers, ecosystem, slog-rs, contextual
Last push: 2026-06-01T00:02:10+00:00

## Health v2 (maintenance only)
Score: 76/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 85, release rhythm 51, longevity 100
- inputs: {"age_days": 3734, "days_push": 94, "days_rel": 326, "gap_med": 2.5, "n_releases_24m": 3}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1708, forks 99 (observed 2026-08-28T04:05:25.463391+00:00)

## What it is
slog is an ecosystem of reusable components for structured, contextual, extensible, and composable logging in Rust. It is a mature, battle-tested library that offers more features than the standard log crate, though the README now recommends considering the tracing crate for new projects.

## Use cases
- add structured logging to a Rust application
- create hierarchical contextual loggers with key-value pairs
- log with high performance in a non-async Rust project
- compose custom logging drains and formats
- replace the standard log crate with richer logging features

## When to choose
- you need mature, stable code and API
- async-specific logging support doesn't benefit you
- you need features tracing is missing
- you want very good logging performance

## When to avoid
- you are starting a new async-heavy Rust project (tracing is the go-to)
- you want the largest community and dev team
- you want a simple logging setup with a shallow learning curve

## Facets
- artifact type: library
- maturity: maintenance
- function: logging
- domain: developer-tools, backend
- platform: rust, cross-platform
- tags: structured-logging, hierarchical-loggers, contextual-logging, rust-ecosystem

## Member repositories
- slog-rs/slog (main) score 76

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:25.463391+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T03:37:01.774281+00:00, confidence not recorded.
  - readme: https://github.com/slog-rs/slog (fetched 2026-08-28T04:05:25.463391+00:00, sha f186f4354e20)
  - homepage: https://slog.rs/ (fetched 2026-08-29T11:11:21.395488+00:00, sha 09190b734d21)
  - registry_crates: https://crates.io/api/v1/crates/slog (fetched 2026-08-29T11:11:21.404401+00:00, sha 514f0741a919)
- Data as of 2026-08-30T08:39:29.467469+00:00.