# mailru/easyjson

Fast JSON serializer for golang.

Repository: https://github.com/mailru/easyjson
Canonical: https://ross.abutalabs.com/products/easyjson
Language: Go
License: MIT
License Family: permissive
Topics: golang, json, json-serialization, code-generation, json-parser, perfomance
Last push: 2026-03-14T14:52:53+00:00

## Health v2 (maintenance only)
Score: 70/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 72, release rhythm 50, longevity 100
- inputs: {"age_days": 3841, "days_push": 172, "days_rel": 172, "gap_med": 179, "n_releases_24m": 4}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 4915, forks 468 (observed 2026-08-28T04:09:02.338273+00:00)

## What it is
easy is a fast JSON serializer for Go that generates marshaler/unmarshaler code for structs via a CLI code generator, avoiding reflection. It claims 4-5x faster marshaling/unmarshaling than the standard encoding/ package.

## Use cases
- serialize Go structs to JSON fast
- unmarshal JSON without reflection overhead
- generate JSON marshaler code for my structs
- speed up JSON encoding in a high-throughput Go API
- customize JSON field naming like snake_case
- replace encoding/ for performance-critical paths

## When to choose
- JSON serialization is a profiling bottleneck in a Go service
- you want generated, inspectable, optimizable marshaler code
- you need options like default omitempty or snake_case keys

## When to avoid
- you need dynamic serialization of arbitrary data without code generation
- your workload is not JSON-bound and standard encoding/ is fast enough
- you cannot run a code generation step in your build

## Facets
- artifact type: library
- maturity: stable
- function: serialization, parser
- domain: developer-tools, backend, apis
- platform: go, cross-platform
- tags: code-generation, performance, no-reflection, golang

## Member repositories
- mailru/easyjson (main) score 70

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:02.338273+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 2026-08-29T18:18:03.439307+00:00, confidence not recorded.
  - readme: https://github.com/mailru/easyjson (fetched 2026-08-28T04:09:02.338273+00:00, sha e352988ce31a)
- Data as of 2026-08-30T08:39:29.467469+00:00.