# samber/lo

💥  A Lodash-style Go library based on Go 1.18+ Generics (map, filter, contains, find...)

Repository: https://github.com/samber/lo
Canonical: https://ross.abutalabs.com/products/lo
Homepage: https://lo.samber.dev
Language: Go
License: MIT
License Family: permissive
Topics: lodash, golang, go, generics, contract, constraints, functional, programming, typesafe, filterable, foldable
Last push: 2026-08-24T04:39:19+00:00

## Health v2 (maintenance only)
Score: 86/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 60, longevity 100
- inputs: {"age_days": 1645, "days_push": 9, "days_rel": 184, "gap_med": 66.5, "n_releases_24m": 7}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 21411, forks 954 (observed 2026-08-28T04:11:31.685549+00:00)

## What it is
samber/lo is a Lodash-style utility library for Go 1.18+ built on generics, providing 300+ type-safe helpers for slices, maps, strings, channels, and functions. It includes subpackages for lazy iteration (Go 1.23+ sequences), in-place mutable operations, and parallel processing with worker pools.

## Use cases
- map filter and reduce slices in go without boilerplate
- deduplicate a slice in go
- find contains and group items in a go slice
- parallelize processing of a collection in go
- lazy iterate over sequences in go 1.23
- replace lodash-style helpers in a go project
- in-place slice filtering for performance-critical go code

## When to choose
- you want hundreds of type-safe collection helpers beyond Go's stdlib slices/maps packages
- you're coming from JavaScript/Python and miss Lodash-style utilities
- you need concurrent or lazy iteration helpers with zero external dependencies

## When to avoid
- you prefer minimal dependencies and only need the few helpers in the standard library
- your team style guide discourages functional-style Go code
- you need reactive processing of infinite event streams (use samber/ro instead)

## Facets
- artifact type: library
- maturity: stable
- function: developer-tools, concurrency, data-science
- domain: developer-tools, cross-platform
- platform: go, cross-platform
- tags: generics, lodash, functional-programming, slices, maps, iterators, parallel-processing, type-safe, algorithms

## Member repositories
- samber/lo (main) score 86

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:31.685549+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 2026-08-29T16:58:06.887958+00:00, confidence not recorded.
  - readme: https://github.com/samber/lo (fetched 2026-08-28T04:11:31.685549+00:00, sha c1a25148fe7a)
  - homepage: https://lo.samber.dev (fetched 2026-08-29T07:56:42.480996+00:00, sha 93192d971d04)
  - site_page: https://lo.samber.dev/docs/about (fetched 2026-08-29T07:56:42.490288+00:00, sha b0719c7c7ff6)
  - site_page: https://lo.samber.dev/docs/getting-started (fetched 2026-08-29T07:56:42.492471+00:00, sha 3f9917e96bb3)
- Data as of 2026-08-30T08:39:29.467469+00:00.