# leventov/Koloboke

Java Collections till the last breadcrumb of memory and performance

Repository: https://github.com/leventov/Koloboke
Canonical: https://ross.abutalabs.com/products/koloboke
Homepage: https://koloboke.com/
Language: Java
License Family: other
Topics: java-collections, java, koloboke, annotation-processor, primitive-specializations, high-performance, hashmap, collections
Last push: 2017-02-01T10:43:20+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 4676, "days_push": 3500, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1017, forks 139 (observed 2026-08-28T04:03:14.560551+00:00)

## What it is
Koloboke is a family of Java collections projects providing primitive-specialized, high-performance implementations of maps and sets as an extension of the Java Collections Framework. It includes an implementation library and an annotation processor (Koloboke Compile) that generates collection implementations.

## Use cases
- replace slow boxed Java collections with primitive-specialized maps and sets
- reduce memory footprint of large hash maps in Java
- generate custom collection implementations via annotation processing
- find a faster HashMap alternative for the JVM
- avoid autoboxing overhead in collection-heavy Java code

## When to choose
- you need memory-efficient primitive-specialized collections on the JVM
- you want drop-in replacements for standard Java maps and sets with better performance
- you need generated implementations for custom collection-like interfaces

## When to avoid
- you need a actively maintained library with recent releases and support
- you work outside the Java/JVM ecosystem
- you only need small collections where performance gains are negligible

## Facets
- artifact type: library
- maturity: maintenance
- function: data-science, developer-tools
- domain: developer-tools, performance
- platform: jvm
- tags: java-collections, primitive-specializations, hashmap, annotation-processor, high-performance, algorithms

## Member repositories
- leventov/Koloboke (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:14.560551+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 2026-08-30T07:11:13.528088+00:00, confidence not recorded.
  - readme: https://github.com/leventov/Koloboke (fetched 2026-08-28T04:03:14.560551+00:00, sha d559552df448)
- Data as of 2026-08-30T08:39:29.467469+00:00.