diff --git a/Gemfile.lock b/Gemfile.lock
index 35bf7947..7b0c1e3b 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -50,7 +50,7 @@ GIT
 
 GIT
   remote: git://github.com/travis-ci/travis-core.git
-  revision: 4cfa414b1d384e518d567c70d572b34a74cbf0bf
+  revision: 3c031d6fb8dbbb415e5d2ef3b2af68a80d361933
   specs:
     travis-core (0.0.1)
       actionmailer (~> 3.2.19)
@@ -61,7 +61,7 @@ GIT
       hashr (~> 0.0.19)
       metriks (~> 0.9.7)
       multi_json
-      pusher (~> 0.12.0)
+      pusher (~> 0.14.0)
       railties (~> 3.2.19)
       rake
       redis (~> 3.0)
@@ -95,6 +95,7 @@ PATH
   remote: .
   specs:
     travis-api (0.0.1)
+      composite_primary_keys (~> 5.0)
       memcachier
       mustermann (~> 0.4)
       pg (~> 0.13.2)
@@ -154,6 +155,8 @@ GEM
     coderay (1.1.0)
     coercible (1.0.0)
       descendants_tracker (~> 0.0.1)
+    composite_primary_keys (5.0.14)
+      activerecord (~> 3.2.0, >= 3.2.9)
     connection_pool (2.1.1)
     daemons (1.1.9)
     dalli (2.7.2)
@@ -168,7 +171,7 @@ GEM
     dotenv (0.7.0)
     equalizer (0.0.9)
     erubis (2.7.0)
-    eventmachine (1.0.4)
+    eventmachine (1.0.7)
     factory_girl (2.4.2)
       activesupport
     faraday (0.9.1)
@@ -187,9 +190,9 @@ GEM
     hashr (0.0.22)
     hike (1.2.3)
     hitimes (1.2.2)
-    httpclient (2.3.4.1)
+    httpclient (2.6.0.1)
     i18n (0.6.11)
-    ice_nine (0.11.0)
+    ice_nine (0.11.1)
     journey (1.0.4)
     json (1.8.1)
     kgio (2.9.2)
@@ -224,10 +227,10 @@ GEM
       coderay (~> 1.1.0)
       method_source (~> 0.8.1)
       slop (~> 3.4)
-    pusher (0.12.0)
-      httpclient (~> 2.3.0)
+    pusher (0.14.4)
+      httpclient (~> 2.5)
       multi_json (~> 1.0)
-      signature (~> 0.1.6)
+      signature (~> 0.1.8)
     rack (1.4.5)
     rack-attack (4.2.0)
       rack
@@ -274,7 +277,7 @@ GEM
       json
       redis (>= 3.0.6)
       redis-namespace (>= 1.3.1)
-    signature (0.1.7)
+    signature (0.1.8)
     simple_states (1.0.1)
       activesupport
       hashr (~> 0.0.10)
@@ -324,7 +327,7 @@ GEM
       raindrops (~> 0.7)
     useragent (0.10.0)
     uuidtools (2.1.5)
-    virtus (1.0.3)
+    virtus (1.0.4)
       axiom-types (~> 0.1)
       coercible (~> 1.0)
       descendants_tracker (~> 0.0, >= 0.0.3)
diff --git a/lib/travis/api/v3/access_control/generic.rb b/lib/travis/api/v3/access_control/generic.rb
index fd68c26f..a8e9d2e0 100644
--- a/lib/travis/api/v3/access_control/generic.rb
+++ b/lib/travis/api/v3/access_control/generic.rb
@@ -24,6 +24,10 @@ module Travis::API::V3
       visible? build.repository
     end
 
+    def branch_visible?(branch)
+      visible? branch.repository
+    end
+
     def organization_visible?(organization)
       unrestricted_api?
     end
diff --git a/lib/travis/api/v3/models.rb b/lib/travis/api/v3/models.rb
index 3504a13a..d12287b3 100644
--- a/lib/travis/api/v3/models.rb
+++ b/lib/travis/api/v3/models.rb
@@ -1,3 +1,5 @@
+require 'composite_primary_keys'
+
 module Travis::API::V3
   module Models
     extend ConstantResolver
diff --git a/lib/travis/api/v3/models/branch.rb b/lib/travis/api/v3/models/branch.rb
new file mode 100644
index 00000000..faa7259e
--- /dev/null
+++ b/lib/travis/api/v3/models/branch.rb
@@ -0,0 +1,8 @@
+module Travis::API::V3
+  class Models::Branch < Model
+    belongs_to :repository
+    belongs_to :last_build, class_name: 'Travis::API::V3::Models::Build'.freeze
+    has_many   :builds,  foreign_key: [:repository_id, :branch], primary_key: [:repository_id, :name], order: 'id DESC'.freeze, conditions: { event_type: 'push' }
+    has_many   :commits, foreign_key: [:repository_id, :branch], primary_key: [:repository_id, :name], order: 'id DESC'.freeze
+  end
+end
diff --git a/lib/travis/api/v3/models/repository.rb b/lib/travis/api/v3/models/repository.rb
index 67aa37e8..3563a17c 100644
--- a/lib/travis/api/v3/models/repository.rb
+++ b/lib/travis/api/v3/models/repository.rb
@@ -2,7 +2,8 @@ module Travis::API::V3
   class Models::Repository < Model
     has_many :commits,     dependent: :delete_all
     has_many :requests,    dependent: :delete_all
-    has_many :builds,      dependent: :delete_all
+    has_many :branches,    dependent: :delete_all, order: 'id DESC'.freeze
+    has_many :builds,      dependent: :delete_all, order: 'id DESC'.freeze
     has_many :permissions, dependent: :delete_all
     has_many :users,       through:   :permissions
 
@@ -12,12 +13,44 @@ module Travis::API::V3
       class_name: 'Travis::API::V3::Models::Build'.freeze,
       order:      'id DESC'.freeze
 
+    has_one :default_branch,
+      foreign_key: [:repository_id, :name],
+      primary_key: [:id,  :default_branch],
+      class_name:  'Travis::API::V3::Models::Branch'.freeze
+
+    after_initialize do
+      update_attributes! default_branch_name: 'master'.freeze unless default_branch_name
+    end
+
     def slug
       @slug ||= "#{owner_name}/#{name}"
     end
 
-    def last_build_on(branch)
-      builds.order('id DESC'.freeze).where(branch: branch, event_type: 'push'.freeze).first
+    def default_branch_name
+      read_attribute(:default_branch)
+    end
+
+    def default_branch_name=(value)
+      write_attribute(:default_branch, value)
+    end
+
+    def default_branch
+      super || branch(default_branch_name, create_without_build: true)
+    end
+
+    # Creates a branch object on the fly if it doesn't exist.
+    #
+    # Will not create a branch object if we don't have any builds for it unless
+    # the create_without_build option is set to true.
+    def branch(name, create_without_build: false)
+      return nil    unless branch = branches.where(name: name).first_or_initialize
+      return branch unless branch.new_record?
+      return nil    unless create_without_build or branch.builds.any?
+      branch.last_build = branch.builds.first
+      branch.save!
+      branch
+    rescue ActiveRecord::RecordNotUnique
+      branches.where(name: name).first
     end
   end
 end
diff --git a/lib/travis/api/v3/queries/branch.rb b/lib/travis/api/v3/queries/branch.rb
new file mode 100644
index 00000000..145b7b02
--- /dev/null
+++ b/lib/travis/api/v3/queries/branch.rb
@@ -0,0 +1,10 @@
+module Travis::API::V3
+  class Queries::Branch < Query
+    params :name
+
+    def find(repository)
+      return repository.branch(name) if name
+      raise WrongParams, 'missing branch.name'.freeze
+    end
+  end
+end
diff --git a/lib/travis/api/v3/queries/repositories.rb b/lib/travis/api/v3/queries/repositories.rb
index 04834ccd..bc374e7b 100644
--- a/lib/travis/api/v3/queries/repositories.rb
+++ b/lib/travis/api/v3/queries/repositories.rb
@@ -11,6 +11,7 @@ module Travis::API::V3
         all = Models::Repository
         all = all.where(active:  bool(active))  unless active.nil?
         all = all.where(private: bool(private)) unless private.nil?
+        all = all.includes(:default_branch) # TODO: use includes params
         all
       end
     end
diff --git a/lib/travis/api/v3/renderer.rb b/lib/travis/api/v3/renderer.rb
index d4fb7735..3747cd61 100644
--- a/lib/travis/api/v3/renderer.rb
+++ b/lib/travis/api/v3/renderer.rb
@@ -10,13 +10,22 @@ module Travis::API::V3
       args.select { |key, value| !value.nil? }
     end
 
-    def href(type, script_name: nil, **args)
-      expander     = EXPANDER_CACHE[[type, script_name, args.keys]] ||= begin
-        resource   = Routes.resources.detect { |r| r.identifier == type }
-        unprefixed = args.keys.reject { |a| a.to_s.include? ?..freeze }
-        route      = resource.route
-        route    &&= Mustermann.new(script_name, type: :identity) + route if script_name and not script_name.empty?
-        generate_expander(route, type, unprefixed)
+    def href(type, string_args = nil, script_name: nil, **args)
+      args.merge! string_args if string_args
+
+      expander      = EXPANDER_CACHE[[type, script_name, args.keys]] ||= begin
+        resource    = Routes.resources.detect { |r| r.identifier == type }
+        route       = resource.route
+        route     &&= Mustermann.new(script_name, type: :identity) + route if script_name and not script_name.empty?
+        key_mapping = {}
+        args.keys.each do |key|
+          case key.to_s
+          when /\./        then key_mapping[key.to_sym]        = key unless key.is_a? Symbol
+          when /^(.+)_id$/ then key_mapping[:"#{$1}.id"]       = key
+          else                  key_mapping[:"#{type}.#{key}"] = key
+          end
+        end
+        generate_expander(route, key_mapping)
       end
 
       expander.call(args)
@@ -24,11 +33,11 @@ module Travis::API::V3
 
     private
 
-    def generate_expander(route, prefix, unprefixed)
+    def generate_expander(route, key_mapping)
       return proc { |**| } unless route.respond_to? :expand
-      proc do |**args|
-        unprefixed.each { |key| args[:"#{prefix}.#{key}"] = args.delete(key) }
-        route.expand(**args)
+      proc do |args|
+        key_mapping.each { |a, b| args[a] = args.delete(b) }
+        route.expand(:ignore, **args)
       end
     end
   end
diff --git a/lib/travis/api/v3/renderer/branch.rb b/lib/travis/api/v3/renderer/branch.rb
new file mode 100644
index 00000000..80445497
--- /dev/null
+++ b/lib/travis/api/v3/renderer/branch.rb
@@ -0,0 +1,8 @@
+require 'travis/api/v3/renderer/model_renderer'
+
+module Travis::API::V3
+  class Renderer::Branch < Renderer::ModelRenderer
+    representation(:minimal,  :name, :last_build)
+    representation(:standard, :name, :repository, :last_build)
+  end
+end
diff --git a/lib/travis/api/v3/renderer/model_renderer.rb b/lib/travis/api/v3/renderer/model_renderer.rb
index 65de8be1..0be52876 100644
--- a/lib/travis/api/v3/renderer/model_renderer.rb
+++ b/lib/travis/api/v3/renderer/model_renderer.rb
@@ -33,8 +33,8 @@ module Travis::API::V3
 
     def href
       return @href if defined? @href # allows setting href to nil
-      return unless self.class.type and model.respond_to? :id and model.id
-      @href = Renderer.href(self.class.type, script_name: script_name, id: model.id)
+      return unless self.class.type and model.respond_to? :attributes
+      @href = Renderer.href(self.class.type, model.attributes, script_name: script_name)
     end
 
     def render(representation)
diff --git a/lib/travis/api/v3/renderer/repository.rb b/lib/travis/api/v3/renderer/repository.rb
index f807b299..947ea727 100644
--- a/lib/travis/api/v3/renderer/repository.rb
+++ b/lib/travis/api/v3/renderer/repository.rb
@@ -5,15 +5,6 @@ module Travis::API::V3
     representation(:minimal,  :id, :slug)
     representation(:standard, :id, :name, :slug, :description, :github_language, :active, :private, :owner, :last_build, :default_branch)
 
-    def default_branch
-      branch_name = model.default_branch || 'master'.freeze
-      {
-        :@type      => 'branch'.freeze,
-        :name       => branch_name,
-        :last_build => model.last_build_on(branch_name)
-      }
-    end
-
     def active
       !!model.active
     end
diff --git a/lib/travis/api/v3/routes.rb b/lib/travis/api/v3/routes.rb
index e911ac78..b0d77179 100644
--- a/lib/travis/api/v3/routes.rb
+++ b/lib/travis/api/v3/routes.rb
@@ -12,6 +12,11 @@ module Travis::API::V3
         get  :find
         post :create
       end
+
+      resource :branch do
+        route '/branch/{branch.name}'
+        get :find
+      end
     end
 
     resource :repositories do
diff --git a/lib/travis/api/v3/routes/dsl.rb b/lib/travis/api/v3/routes/dsl.rb
index e4e08df2..fbd71c8f 100644
--- a/lib/travis/api/v3/routes/dsl.rb
+++ b/lib/travis/api/v3/routes/dsl.rb
@@ -34,7 +34,7 @@ module Travis::API::V3
     end
 
     def route(value)
-      current_resource.route = prefix + value
+      current_resource.route = Mustermann.new(prefix) + Mustermann.new(value)
     end
 
     def get(*args)
diff --git a/lib/travis/api/v3/services.rb b/lib/travis/api/v3/services.rb
index 5e543412..e5180864 100644
--- a/lib/travis/api/v3/services.rb
+++ b/lib/travis/api/v3/services.rb
@@ -2,6 +2,7 @@ module Travis::API::V3
   module Services
     extend ConstantResolver
 
+    Branch        = Module.new { extend Services }
     Build         = Module.new { extend Services }
     Organization  = Module.new { extend Services }
     Organizations = Module.new { extend Services }
diff --git a/lib/travis/api/v3/services/branch/find.rb b/lib/travis/api/v3/services/branch/find.rb
new file mode 100644
index 00000000..927b1a87
--- /dev/null
+++ b/lib/travis/api/v3/services/branch/find.rb
@@ -0,0 +1,7 @@
+module Travis::API::V3
+  class Services::Branch::Find < Service
+    def run!
+      find(:branch, find(:repository))
+    end
+  end
+end
diff --git a/spec/v3/service_index_spec.rb b/spec/v3/service_index_spec.rb
index ce53c2e4..0925bb75 100644
--- a/spec/v3/service_index_spec.rb
+++ b/spec/v3/service_index_spec.rb
@@ -12,6 +12,8 @@ describe Travis::API::V3::ServiceIndex do
         "find"              => [{"request-method"=>"GET",  "uri-template"=>"#{path}repo/{repository.id}"}] },
       "repositories"        =>  {
         "for_current_user"  => [{"request-method"=>"GET",  "uri-template"=>"#{path}repos"}] },
+      "branch"              =>  {
+        "find"              => [{"request-method"=>"GET",  "uri-template"=>"#{path}repo/{repository.id}/branch/{branch.name}"}]},
       "build"               =>  {
         "find"              => [{"request-method"=>"GET",  "uri-template"=>"#{path}build/{build.id}"}] },
       "organizations"       =>  {
diff --git a/spec/v3/services/branch/find_spec.rb b/spec/v3/services/branch/find_spec.rb
new file mode 100644
index 00000000..8d909aa1
--- /dev/null
+++ b/spec/v3/services/branch/find_spec.rb
@@ -0,0 +1,29 @@
+require 'spec_helper'
+
+describe Travis::API::V3::Services::Repository::Find do
+  let(:repo) { Travis::API::V3::Models::Repository.where(owner_name: 'svenfuchs', name: 'minimal').first }
+  before { repo.default_branch.save! }
+
+  describe "public repository, existing branch" do
+    before     { get("/v3/repo/#{repo.id}/branch/master") }
+    example    { expect(last_response).to be_ok           }
+    example    { expect(JSON.load(body)).to be ==         {
+      "@type"         => "branch",
+      "@href"         => "/v3/repo/#{repo.id}/branch/master",
+      "name"          => "master",
+      "repository"    => {
+        "@type"       => "repository",
+        "@href"       => "/v3/repo/#{repo.id}",
+        "id"          => repo.id,
+        "slug"        => "svenfuchs/minimal"},
+      "last_build"    => {
+        "@type"       => "build",
+        "@href"       => "/v3/build/#{repo.last_build.id}",
+        "id"          => repo.last_build.id,
+        "number"      => "3",
+        "state"       => "configured",
+        "duration"    => nil,
+        "started_at"  => "2010-11-12T13:00:00Z",
+        "finished_at" => nil}}}
+  end
+end
\ No newline at end of file
diff --git a/spec/v3/services/repositories/for_current_user_spec.rb b/spec/v3/services/repositories/for_current_user_spec.rb
index 4f61803b..042cdae3 100644
--- a/spec/v3/services/repositories/for_current_user_spec.rb
+++ b/spec/v3/services/repositories/for_current_user_spec.rb
@@ -40,6 +40,7 @@ describe Travis::API::V3::Services::Repositories::ForCurrentUser do
           "finished_at"   => "2010-11-12T12:30:20Z"},
         "default_branch"  => {
           "@type"         => "branch",
+          "@href"         => "/v3/repo/#{repo.id}/branch/master",
           "name"          => "master",
           "last_build"    => {
             "@type"       => "build",
diff --git a/spec/v3/services/repository/find_spec.rb b/spec/v3/services/repository/find_spec.rb
index 292a1d2c..9cce296f 100644
--- a/spec/v3/services/repository/find_spec.rb
+++ b/spec/v3/services/repository/find_spec.rb
@@ -31,6 +31,7 @@ describe Travis::API::V3::Services::Repository::Find do
         "finished_at"   => "2010-11-12T12:30:20Z"},
       "default_branch"  => {
         "@type"         => "branch",
+        "@href"         => "/v3/repo/#{repo.id}/branch/master",
         "name"          => "master",
         "last_build"    => {
           "@type"       => "build",
@@ -114,6 +115,7 @@ describe Travis::API::V3::Services::Repository::Find do
         "finished_at"   => "2010-11-12T12:30:20Z"},
       "default_branch"  => {
         "@type"         => "branch",
+        "@href"         => "/v3/repo/#{repo.id}/branch/master",
         "name"          => "master",
         "last_build"    => {
           "@type"       => "build",
@@ -182,6 +184,7 @@ describe Travis::API::V3::Services::Repository::Find do
         "finished_at"   => "2010-11-12T12:30:20Z"},
       "default_branch"  => {
         "@type"         => "branch",
+        "@href"         => "/v3/repo/#{repo.id}/branch/master",
         "name"          => "master",
         "last_build"    => {
           "@type"       => "build",
@@ -256,6 +259,7 @@ describe Travis::API::V3::Services::Repository::Find do
         "finished_at"   => "2010-11-12T12:30:20Z"},
       "default_branch"  => {
         "@type"         => "branch",
+        "@href"         => "/v3/repo/#{repo.id}/branch/master",
         "name"          => "master",
         "last_build"    => {
           "@type"       => "build",
diff --git a/travis-api.gemspec b/travis-api.gemspec
index d4e1c079..548ced44 100644
--- a/travis-api.gemspec
+++ b/travis-api.gemspec
@@ -288,14 +288,15 @@ Gem::Specification.new do |s|
   s.add_dependency 'travis-support'
   s.add_dependency 'travis-core'
 
-  s.add_dependency 'pg',              '~> 0.13.2'
-  s.add_dependency 'thin',            '~> 1.4'
-  s.add_dependency 'sinatra',         '~> 1.3'
-  s.add_dependency 'sinatra-contrib', '~> 1.3'
-  s.add_dependency 'mustermann',      '~> 0.4'
-  s.add_dependency 'redcarpet',       '~> 2.1'
-  s.add_dependency 'rack-ssl',        '~> 1.3', '>= 1.3.3'
-  s.add_dependency 'rack-contrib',    '~> 1.1'
+  s.add_dependency 'pg',                     '~> 0.13.2'
+  s.add_dependency 'composite_primary_keys', '~> 5.0'
+  s.add_dependency 'thin',                   '~> 1.4'
+  s.add_dependency 'sinatra',                '~> 1.3'
+  s.add_dependency 'sinatra-contrib',        '~> 1.3'
+  s.add_dependency 'mustermann',             '~> 0.4'
+  s.add_dependency 'redcarpet',              '~> 2.1'
+  s.add_dependency 'rack-ssl',               '~> 1.3', '>= 1.3.3'
+  s.add_dependency 'rack-contrib',           '~> 1.1'
   s.add_dependency 'memcachier'
   s.add_dependency 'useragent'
 end