View source for Merb

{{other uses}}
{{Infobox software
| name = Merb
| logo = 
| screenshot = [[File:Merb screenshot.png|300px|frameless]]
| caption = {{nowrap| All you need… nil you don’t }}
| author = Ezra Zygmuntowicz
| developer = Ezra Zygmuntowicz & Yehuda Katz
| released = 
| latest release version = 1.1.3<ref>{{cite web|title=1.1.3|url=https://github.com/merb/merb/releases/tag/1.1.3|website=GitHub}}</ref>
| latest release date = {{start date|2010|07|12}}
| operating system = [[Cross-platform]]
| programming language = [[Ruby (programming language)|Ruby]]
| genre = [[Web application framework]]
| license = [[MIT License]]
| website = [https://web.archive.org/web/20081204002911/http://merbivore.com/ http://www.merbivore.com ]
| discontinued = yes
| title = Merb: No code is faster than no code<ref>{{cite web|last1=Zygmuntowicz|first1=Ezra|title=No Code is Faster Than No Code|url=https://twitter.com/ezmobius/status/154477982193418240|website=Twitter|access-date=2 April 2015}}</ref><ref>{{cite web | last1=Grosenbach | first1=Geoffrey | title=Origin of, "No code is faster than no code." | url=https://twitter.com/ezmobius/status/61523924546093056 | website=Twitter | publisher=Ezra Zygmuntowicz | access-date=2 April 2015}}</ref>
}}

'''Merb''' is a discontinued [[model–view–controller]] [[web framework]] in [[Ruby (programming language)|Ruby]], notable as a precursor to Rails 3. It brought increased focus on speed and modularity to Rails 3.<ref name="Boone">{{cite web|last=Boone |first=Paul |date=18 Sep 2008 |title=Rails/Merb performance comparison (on mongrel, jruby, tomcat, glassfish) |url=http://www.mindbucket.com/2008/09/18/rails-merb-performance-comparison-on-mongrel-jruby-tomcat-glassfish/ |archive-url=https://web.archive.org/web/20110714095129/http://www.mindbucket.com/2008/09/18/rails-merb-performance-comparison-on-mongrel-jruby-tomcat-glassfish/ |url-status=dead |archive-date=14 July 2011 |work=mindbucket.com}}</ref><ref>{{cite web|url=https://edgeguides.rubyonrails.org/3_0_release_notes.html |title=Ruby on Rails 3.0 Release Notes |website=Ruby on Rails Guides |access-date=18 July 2020}}</ref> The name Merb is a contraction of "[[Mongrel (web server)|Mongrel]]" and "[[eRuby#erb|Erb]]".<ref>{{cite web |url=http://osdir.com/ml/lang.ruby.mongrel.general/2006-10/msg00105.html |last=Zygmuntowicz |first=Ezra |title=ANN: Merb, Mongrel+Erb |work=osdir.com] |date=18 Oct 2006 |url-status=dead |archive-url=https://web.archive.org/web/20091231134535/http://osdir.com/ml/lang.ruby.mongrel.general/2006-10/msg00105.html |archive-date=2009-12-31}}</ref>

== Precursor to and merge with Rails 3 ==

Merb began as a "clean-room" implementation<ref>{{cite web|url=http://brainspl.at/articles/2008/12/23/merb-is-rails |title=Merb *is* Rails |last=Zygmuntowicz |first=Ezra |date=23 Dec 2008}}</ref> of the [[Ruby on Rails|Rails]] [[Model-View-Controller|controller stack]] but grew to incorporate several ideas that deviated from Rails's spirit and methodology at the time, most notably [[Modular programming|component modularity]], extensible [[Application programming interface#Web APIs|API]] design, and [[Scalability#Scale vertically .28scale up.29|vertical scalability]]. It was developed by Ezra Zygmuntowicz and Yehuda Katz. Most of these capabilities were added to Rails during the Rails 3/Merb merger.<ref name="dhh-merged-into-rails">{{cite web|last=Hansson |first=David Heinemeier |author-link=David Heinemeier Hansson |title=Merb gets merged into Rails 3! |url=https://weblog.rubyonrails.org/2008/12/23/merb-gets-merged-into-rails-3/ |date=23 Dec 2008 |work=weblog.rubyonrails.org |access-date=18 July 2020}}</ref><ref name="yehuda-rails3">{{cite web|last=Katz |first=Yehuda |author-link=Yehuda Katz (web developer) |date=23 Dec 2008 |url=http://yehudakatz.com/2008/12/23/rails-and-merb-merge/ |title=Rails and Merb Merge |work=yehudakatz.com}}</ref> Merb was first released at the 2008 [[RubyConf]]<ref>{{cite web |url=http://merbist.com/2008/11/09/merb-1-0-released/ |title=Merb 1.0 released |last=Aimonetti |first=Matt |work=Merbist |date=9 Nov 2008}}</ref> and development has since stopped; Rails 3, therefore, serves as both the successor to Rails 2 and the successor to Merb.

== Differences from Ruby on Rails ==

Merb's design attempted to address several criticisms of [[Ruby on Rails|Rails]] 2: 
* lack of component modularity ([[Monolithic system|monolithic]] design)
* lack of an extensible API
* lack of vertical scalability

=== Modularity ===

Merb itself encompassed only the controller layer in [[Model–view–controller|MVC]] architecture, and used a suite of complementary, optional plugins together to assemble applications. The primary integration points were the web server interface, the model layer, the view layer, and controller extensions and add-ons. Merb's default application stack incorporated [[Datamapper]] for models, ERB for views, and [[Rack (web server interface)|Rack]] and Mongrel as the web server layer.<ref>{{cite web |url=http://rubygems.org/gems/merb-core |date=23 Mar 2010 |title=merb-core gem dependencies}}</ref><ref>{{cite web |url=http://rubygems.org/gems/merb |date=23 Mar 2010 |title=merb gem dependencies}}</ref>

=== Well-defined API ===
Before the Merb / Rails 3 merge, Rails lacked a well-defined, documented, public API for extensions and plug-ins, leading to issues when Rails changes broke [[monkey patch|monkey-patches]] performed by plug-ins. With the Rails 3 / Merb merge, Rails gained a defined public API with a test suite,<ref name="yehuda-rails3" /> giving users and plugin developers a clearer, more stable API to build against, reducing plugin breakage from release to release.<ref name="dhh-merged-into-rails" />

=== Performance and scalability ===
Some early versions of Rails received bad publicity for lack of performance, frequently due to developer confusion about ActiveRecord queries. [[David Heinemeier Hansson]], the creator of Rails, stated that Merb re-wrote many core Rails pieces to be faster,<ref name="dhh-merged-into-rails" /> and incorporated those changes from Merb in the Rails 3 merge, promising users that "Rails 3 will get all the performance attention that the Merb guys are known for".<ref name="dhh-merged-into-rails" />

== References ==
{{reflist}}

== External links ==
* [https://web.archive.org/web/20081204002911/http://merbivore.com/ Merbivore - Official Merb Site]

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