# amatsuda/jb

A simple and fast JSON API template engine for Ruby on Rails

Repository: https://github.com/amatsuda/jb
Canonical: https://ross.abutalabs.com/products/jb
Language: Ruby
License: MIT
License Family: permissive
Topics: rails, json, template-engine, jbuilder
Last push: 2026-01-20T17:19:01+00:00

## Health v2 (maintenance only)
Score: 61/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 63, release rhythm 35, longevity 100
- inputs: {"age_days": 3715, "days_push": 225, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1315, forks 42 (observed 2026-08-28T04:04:20.552655+00:00)

## What it is
Jb is a JSON API template engine for Ruby on Rails that serves as a simpler and faster alternative to Jbuilder. Templates are plain Ruby code returning Hash or Array objects that get serialized to JSON, with no custom DSL to learn.

## Use cases
- render JSON API responses in Rails views
- replace Jbuilder with a faster template engine
- build JSON payloads using plain Ruby hashes
- render JSON collections with working partials
- dynamically construct JSON attribute names
- generate top-level JSON arrays for index actions

## When to choose
- you're on Rails and find Jbuilder's DSL awkward or slow
- you want JSON templates that are just Ruby code
- you need render_partial with :collection to actually render collections
- you prefer modern Ruby hash syntax that mirrors JSON

## When to avoid
- you're not using Ruby on Rails
- you need a framework-agnostic JSON serializer
- your team already standardizes on Jbuilder or serializers like active_model_serializers

## Facets
- artifact type: library
- maturity: stable
- function: templating, serialization, web-framework
- domain: web-development, backend, apis
- platform: ruby
- tags: rails, -templates, jbuilder-alternative, view-layer, web-server

## Member repositories
- amatsuda/jb (main) score 61

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:20.552655+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 2026-08-30T04:48:40.596019+00:00, confidence not recorded.
  - readme: https://github.com/amatsuda/jb (fetched 2026-08-28T04:04:20.552655+00:00, sha 50578c8809e4)
- Data as of 2026-08-30T08:39:29.467469+00:00.