# uber-go/zap

Blazing fast, structured, leveled logging in Go.

Repository: https://github.com/uber-go/zap
Canonical: https://ross.abutalabs.com/products/zap
Homepage: https://pkg.go.dev/go.uber.org/zap
Language: Go
License: MIT
License Family: permissive
Topics: golang, logging, structured-logging, zap
Last push: 2026-08-25T20:39:03+00:00

## Health v2 (maintenance only)
Score: 82/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 49, longevity 100
- inputs: {"age_days": 3849, "days_push": 8, "days_rel": 128, "gap_med": 276.0, "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 24644, forks 1549 (observed 2026-08-28T04:11:37.566314+00:00)

## What it is
Zap is a fast, structured, leveled logging library for Go, developed by Uber. It offers a zero-allocation JSON encoder and two APIs: a high-performance strongly-typed Logger and a more convenient SugaredLogger.

## Use cases
- add structured logging to a Go service
- log in performance-critical hot paths with minimal allocations
- emit JSON logs for production log aggregation
- replace logrus with a faster logging library
- log with levels and typed fields in Go

## When to choose
- you need very fast, low-allocation structured logging in Go
- you want JSON output for log pipelines
- you need a mature, widely adopted logging library

## When to avoid
- you want a simple human-readable logger with minimal setup
- your project targets Go versions outside the two most recent minors

## Facets
- artifact type: library
- maturity: stable
- function: logging, serialization
- domain: developer-tools, backend
- platform: go, cross-platform
- tags: structured-logging, high-performance, zero-allocation, -encoder

## Member repositories
- uber-go/zap (main) score 82

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:37.566314+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 2026-08-29T16:56:11.017604+00:00, confidence not recorded.
  - readme: https://github.com/uber-go/zap (fetched 2026-08-28T04:11:37.566314+00:00, sha ea8b08d384ba)
  - homepage: https://pkg.go.dev/go.uber.org/zap (fetched 2026-08-29T07:53:23.283611+00:00, sha ffb425e5c2dd)
  - site_page: https://pkg.go.dev/about (fetched 2026-08-29T07:53:23.295178+00:00, sha 757852027879)
  - site_page: https://go.dev/about (fetched 2026-08-29T07:53:23.297233+00:00, sha 8b6453863a90)
  - site_page: https://go.dev/project (fetched 2026-08-29T07:53:23.300072+00:00, sha d5ca00bb378b)
- Data as of 2026-08-30T08:39:29.467469+00:00.