# igrigorik/em-synchrony

Fiber aware EventMachine clients and convenience classes

Repository: https://github.com/igrigorik/em-synchrony
Canonical: https://ross.abutalabs.com/products/em-synchrony
Homepage: http://www.igvita.com/2010/03/22/untangling-evented-code-with-ruby-fibers
Language: Ruby
License: MIT
License Family: permissive
Last push: 2018-01-26T20:36:57+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 6015, "days_push": 3141, "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 1035, forks 145 (observed 2026-08-28T04:03:19.044362+00:00)

## What it is
A Ruby library providing Fiber-aware EventMachine clients and convenience primitives such as connection pools, iterators, and synchronization classes. It lets developers write evented, non-blocking code in a synchronous style using Ruby Fibers.

## Use cases
- write async eventmachine code without callback nesting
- fiber-aware connection pooling for mysql2 or redis
- run concurrent http requests with em-http-request in synchronous style
- control concurrency when iterating over async tasks
- convert callback-based async functions into synchronous calls
- use fiber-aware mutex, condition variables, and threads

## When to choose
- you maintain a legacy Ruby EventMachine codebase that already uses em-synchrony
- you need synchronous-style code on top of EventMachine clients in Ruby
- you want fiber-based concurrency control primitives in Ruby

## When to avoid
- starting a new Ruby project - prefer modern async gems like async or concurrent-ruby
- you are not using EventMachine as your reactor
- you need actively maintained software with recent releases

## Facets
- artifact type: library
- maturity: maintenance
- function: concurrency, http-client, database-driver, caching, message-queue
- domain: developer-tools, backend, networking
- platform: ruby
- tags: eventmachine, fibers, async, reactor-pattern, connection-pool, ruby-gem, linux, macos

## Member repositories
- igrigorik/em-synchrony (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:19.044362+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 2026-08-30T07:04:54.449032+00:00, confidence not recorded.
  - readme: https://github.com/igrigorik/em-synchrony (fetched 2026-08-28T04:03:19.044362+00:00, sha a5eb7d4c4813)
  - homepage: http://www.igvita.com/2010/03/22/untangling-evented-code-with-ruby-fibers (fetched 2026-08-29T13:05:43.066881+00:00, sha 445e78472179)
  - site_page: https://www.igvita.com/ (fetched 2026-08-29T13:05:43.076320+00:00, sha 461eab8cd7b0)
- Data as of 2026-08-30T08:39:29.467469+00:00.