diff --git a/app/controllers/projects/jobs_controller.rb b/app/controllers/projects/jobs_controller.rb
index d2cd1cfdab8..9b8a9eedfef 100644
--- a/app/controllers/projects/jobs_controller.rb
+++ b/app/controllers/projects/jobs_controller.rb
@@ -45,6 +45,17 @@ class Projects::JobsController < Projects::ApplicationController
     @builds = @project.pipelines.find_by_sha(@build.sha).builds.order('id DESC')
     @builds = @builds.where("id not in (?)", @build.id)
     @pipeline = @build.pipeline
+
+    respond_to do |format|
+      format.html
+      format.json do
+        Gitlab::PollingInterval.set_header(response, interval: 10_000)
+
+        render json: BuildSerializer
+          .new(project: @project, current_user: @current_user)
+          .represent_status(@build, {}, BuildDetailsEntity)
+      end
+    end
   end
 
   def trace
diff --git a/app/models/ci/build.rb b/app/models/ci/build.rb
index 60b71ff0d93..ff6860bc181 100644
--- a/app/models/ci/build.rb
+++ b/app/models/ci/build.rb
@@ -204,14 +204,17 @@ module Ci
     end
 
     def merge_request
-      merge_requests = MergeRequest.includes(:merge_request_diff)
-                                   .where(source_branch: ref,
-                                          source_project: pipeline.project)
-                                   .reorder(iid: :asc)
+      @merge_request ||=
+        begin
+          merge_requests = MergeRequest.includes(:merge_request_diff)
+            .where(source_branch: ref,
+                   source_project: pipeline.project)
+            .reorder(iid: :asc)
 
-      merge_requests.find do |merge_request|
-        merge_request.commits_sha.include?(pipeline.sha)
-      end
+          merge_requests.find do |merge_request|
+            merge_request.commits_sha.include?(pipeline.sha)
+          end
+        end
     end
 
     def repo_url
diff --git a/app/serializers/build_details_entity.rb b/app/serializers/build_details_entity.rb
new file mode 100644
index 00000000000..08c5e69180c
--- /dev/null
+++ b/app/serializers/build_details_entity.rb
@@ -0,0 +1,34 @@
+class BuildDetailsEntity < BuildEntity
+  expose :coverage, :erased_at, :duration
+  expose :tag_list, as: :tags
+
+  expose :artifacts, using: BuildArtifactEntity
+  expose :runner, using: RunnerEntity
+  expose :pipeline, using: PipelineEntity
+
+  expose :merge_request_path do |build|
+    merge_request = build.merge_request
+    project = build.project
+
+    if merge_request.nil? || !can?(request.current_user, :read_merge_request, project)
+      nil
+    else
+      namespace_project_merge_request_path(project.namespace, project, merge_request)
+    end
+  end
+
+  expose :new_issue_path do |build|
+    project = build.project
+
+    unless build.failed? && can?(request.current_user, :create_issue, project)
+      nil
+    else
+      new_namespace_project_issue_path(project.namespace, project)
+    end
+  end
+
+  expose :raw_path do |build|
+    project = build.project
+    raw_namespace_project_build_path(project.namespace, project, build)
+  end
+end
diff --git a/app/serializers/build_serializer.rb b/app/serializers/build_serializer.rb
index 79b67001199..7b501a52604 100644
--- a/app/serializers/build_serializer.rb
+++ b/app/serializers/build_serializer.rb
@@ -1,8 +1,10 @@
 class BuildSerializer < BaseSerializer
   entity BuildEntity
 
-  def represent_status(resource)
+  def represent_status(resource, opts = {}, entity_class = nil)
     data = represent(resource, { only: [:status] })
     data.fetch(:status, {})
+
+    represent(resource, opts, entity_class)
   end
 end
diff --git a/app/serializers/runner_entity.rb b/app/serializers/runner_entity.rb
new file mode 100644
index 00000000000..77d6de6e84c
--- /dev/null
+++ b/app/serializers/runner_entity.rb
@@ -0,0 +1,3 @@
+class RunnerEntity < Grape::Entity
+  expose :id, :name, :description
+end
diff --git a/changelogs/unreleased/zj-job-view-goes-real-time.yml b/changelogs/unreleased/zj-job-view-goes-real-time.yml
new file mode 100644
index 00000000000..376c9dfa65f
--- /dev/null
+++ b/changelogs/unreleased/zj-job-view-goes-real-time.yml
@@ -0,0 +1,4 @@
+---
+title: Job details page update real time
+merge_request: 11651
+author:
diff --git a/lib/gitlab/etag_caching/router.rb b/lib/gitlab/etag_caching/router.rb
index d137cc1bae6..53f3f442bc3 100644
--- a/lib/gitlab/etag_caching/router.rb
+++ b/lib/gitlab/etag_caching/router.rb
@@ -9,7 +9,9 @@ module Gitlab
       #   - Ending in `noteable/issue/<id>/notes` for the `issue_notes` route
       #   - Ending in `issues/id`/realtime_changes` for the `issue_title` route
       USED_IN_ROUTES = %w[noteable issue notes issues realtime_changes
-                          commit pipelines merge_requests new].freeze
+                          commit pipelines merge_requests builds
+                          new].freeze
+
       RESERVED_WORDS = Gitlab::PathRegex::ILLEGAL_PROJECT_PATH_WORDS - USED_IN_ROUTES
       RESERVED_WORDS_REGEX = Regexp.union(*RESERVED_WORDS.map(&Regexp.method(:escape)))
       ROUTES = [
@@ -40,6 +42,10 @@ module Gitlab
         Gitlab::EtagCaching::Router::Route.new(
           %r(^(?!.*(#{RESERVED_WORDS_REGEX})).*/pipelines/\d+\.json\z),
           'project_pipeline'
+        ),
+        Gitlab::EtagCaching::Router::Route.new(
+          %r(^(?!.*(#{RESERVED_WORDS_REGEX})).*/builds/\d+\.json\z),
+          'project_build'
         )
       ].freeze
 
diff --git a/spec/controllers/projects/jobs_controller_spec.rb b/spec/controllers/projects/jobs_controller_spec.rb
index 838bdae1445..7109310b6df 100644
--- a/spec/controllers/projects/jobs_controller_spec.rb
+++ b/spec/controllers/projects/jobs_controller_spec.rb
@@ -101,26 +101,48 @@ describe Projects::JobsController do
   end
 
   describe 'GET show' do
-    context 'when build exists' do
-      let!(:build) { create(:ci_build, pipeline: pipeline) }
+    let!(:build) { create(:ci_build, :failed, pipeline: pipeline) }
 
-      before do
-        get_show(id: build.id)
+    context 'when requesting HTML' do
+      context 'when build exists' do
+        before do
+          get_show(id: build.id)
+        end
+
+        it 'has a build' do
+          expect(response).to have_http_status(:ok)
+          expect(assigns(:build).id).to eq(build.id)
+        end
       end
 
-      it 'has a build' do
-        expect(response).to have_http_status(:ok)
-        expect(assigns(:build).id).to eq(build.id)
+      context 'when build does not exist' do
+        before do
+          get_show(id: 1234)
+        end
+
+        it 'renders not_found' do
+          expect(response).to have_http_status(:not_found)
+        end
       end
     end
 
-    context 'when build does not exist' do
+    context 'when requesting JSON' do
+      let(:merge_request) { create(:merge_request, source_project: project) }
+
       before do
-        get_show(id: 1234)
+        project.add_developer(user)
+        sign_in(user)
+
+        allow_any_instance_of(Ci::Build).to receive(:merge_request).and_return(merge_request)
+
+        get_show(id: build.id, format: :json)
       end
 
-      it 'renders not_found' do
-        expect(response).to have_http_status(:not_found)
+      it 'exposes needed information' do
+        expect(response).to have_http_status(:ok)
+        expect(json_response['new_issue_path']).to end_with('/issues/new')
+        expect(json_response['raw_path']).to match(/builds\/\d+\/raw\z/)
+        expect(json_response['merge_request_path']).to match(/merge_requests\/\d+\z/)
       end
     end
 
diff --git a/spec/lib/gitlab/etag_caching/router_spec.rb b/spec/lib/gitlab/etag_caching/router_spec.rb
index 46a238b17f4..22494f4dcf5 100644
--- a/spec/lib/gitlab/etag_caching/router_spec.rb
+++ b/spec/lib/gitlab/etag_caching/router_spec.rb
@@ -67,6 +67,17 @@ describe Gitlab::EtagCaching::Router do
     expect(result.name).to eq 'merge_request_pipelines'
   end
 
+  it 'matches build endpoint' do
+    env = build_env(
+      '/my-group/my-project/builds/234.json'
+    )
+
+    result = described_class.match(env)
+
+    expect(result).to be_present
+    expect(result.name).to eq 'project_build'
+  end
+
   it 'does not match blob with confusing name' do
     env = build_env(
       '/my-group/my-project/blob/master/pipelines.json'
diff --git a/spec/serializers/build_details_entity_spec.rb b/spec/serializers/build_details_entity_spec.rb
new file mode 100644
index 00000000000..4b827a0994c
--- /dev/null
+++ b/spec/serializers/build_details_entity_spec.rb
@@ -0,0 +1,39 @@
+require 'spec_helper'
+
+describe BuildDetailsEntity do
+  it 'inherits from BuildEntity' do
+    expect(described_class).to be < BuildEntity
+  end
+
+  describe '#as_json' do
+    let(:project) { create(:project, :repository) }
+    let(:user) { create(:user) }
+    let!(:build) { create(:ci_build, :failed, project: project) }
+    let(:request) { double('request') }
+    let(:entity) { described_class.new(build, request: request, current_user: user, project: project) }
+    subject { entity.as_json }
+
+    before do
+      allow(request).to receive(:current_user).and_return(user)
+
+      project.add_master(user)
+    end
+
+    context 'when the user has access to issues and merge requests' do
+      let!(:merge_request) { create(:merge_request, source_project: project) }
+
+      it 'contains the needed key value pairs' do
+        expect(subject).to include(:coverage, :erased_at, :duration)
+        expect(subject).to include(:artifacts, :runner, :pipeline)
+        expect(subject).to include(:raw_path, :merge_request_path, :new_issue_path)
+      end
+    end
+
+    context 'when the user can only read the build' do
+      it "won't display the paths to issues and merge requests" do
+        expect(subject['new_issue_path']).to be_nil
+        expect(subject['merge_request_path']).to be_nil
+      end
+    end
+  end
+end
diff --git a/spec/serializers/runner_entity_spec.rb b/spec/serializers/runner_entity_spec.rb
new file mode 100644
index 00000000000..eb662a10b7e
--- /dev/null
+++ b/spec/serializers/runner_entity_spec.rb
@@ -0,0 +1,14 @@
+require 'spec_helper'
+
+describe RunnerEntity do
+  let(:runner) { build(:ci_runner) }
+  let(:entity) { described_class.represent(runner) }
+
+  describe '#as_json' do
+    subject { entity.as_json }
+
+    it 'contains required fields' do
+      expect(subject).to include(:id, :name, :description)
+    end
+  end
+end