diff --git a/changelogs/unreleased/require-all-templates-to-include-default-stages.yml b/changelogs/unreleased/require-all-templates-to-include-default-stages.yml
new file mode 100644
index 0000000000000000000000000000000000000000..de8b07160bae74d5d49861bdb91ea2b25ea5c6da
--- /dev/null
+++ b/changelogs/unreleased/require-all-templates-to-include-default-stages.yml
@@ -0,0 +1,5 @@
+---
+title: Require all templates to use default stages
+merge_request: 26954
+author:
+type: fixed
diff --git a/lib/gitlab/ci/config.rb b/lib/gitlab/ci/config.rb
index 15643fa03ac2d1ab008c31e9d1d790d240322320..f187e4569930e6fbf698a2ca7be9542b23917688 100644
--- a/lib/gitlab/ci/config.rb
+++ b/lib/gitlab/ci/config.rb
@@ -73,17 +73,13 @@ module Gitlab
       def build_config(config, project:, sha:, user:)
         initial_config = Gitlab::Config::Loader::Yaml.new(config).load!
 
-        if project
-          process_external_files(initial_config, project: project, sha: sha, user: user)
-        else
-          initial_config
-        end
+        process_external_files(initial_config, project: project, sha: sha, user: user)
       end
 
       def process_external_files(config, project:, sha:, user:)
         Config::External::Processor.new(config,
           project: project,
-          sha: sha || project.repository.root_ref_sha,
+          sha: sha || project&.repository&.root_ref_sha,
           user: user,
           expandset: Set.new).perform
       end
diff --git a/lib/gitlab/ci/config/external/file/local.rb b/lib/gitlab/ci/config/external/file/local.rb
index 229a06451e866943e4c799a642f6d34e8fb5d7f8..cac321ec4a6d8f37a2281e9a2ba349635b90b34d 100644
--- a/lib/gitlab/ci/config/external/file/local.rb
+++ b/lib/gitlab/ci/config/external/file/local.rb
@@ -21,7 +21,9 @@ module Gitlab
             private
 
             def validate_content!
-              if content.nil?
+              if context.project&.repository.nil?
+                errors.push("Local file `#{location}` does not have project!")
+              elsif content.nil?
                 errors.push("Local file `#{location}` does not exist!")
               elsif content.blank?
                 errors.push("Local file `#{location}` is empty!")
diff --git a/lib/gitlab/ci/templates/Android-Fastlane.gitlab-ci.yml b/lib/gitlab/ci/templates/Android-Fastlane.gitlab-ci.yml
index 8e767b223608d31bbb5067b7454881d69bf0f313..120272200c6fee2a8e1b556ca7e02f9612613d85 100644
--- a/lib/gitlab/ci/templates/Android-Fastlane.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/Android-Fastlane.gitlab-ci.yml
@@ -6,6 +6,7 @@ stages:
   - environment
   - build
   - test
+  - deploy
   - internal
   - alpha
   - beta
diff --git a/lib/gitlab/ci/templates/Android.gitlab-ci.yml b/lib/gitlab/ci/templates/Android.gitlab-ci.yml
index c169e3f768603f2c336a6c5e49202277276e57c7..2be7f9334625c629e5b9f426410e35e8503322d4 100644
--- a/lib/gitlab/ci/templates/Android.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/Android.gitlab-ci.yml
@@ -24,10 +24,6 @@ before_script:
   - yes | android-sdk-linux/tools/bin/sdkmanager --licenses
   - set -o pipefail
 
-stages:
-  - build
-  - test
-
 lintDebug:
   stage: build
   script:
diff --git a/lib/gitlab/ci/templates/Auto-DevOps.gitlab-ci.yml b/lib/gitlab/ci/templates/Auto-DevOps.gitlab-ci.yml
index b3eec2b62104b1661bfe1ec4004674d979e4b970..939112e6e410a41bbc4c4ad88b84a55b00a99ad2 100644
--- a/lib/gitlab/ci/templates/Auto-DevOps.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/Auto-DevOps.gitlab-ci.yml
@@ -60,6 +60,7 @@ variables:
 stages:
   - build
   - test
+  - deploy # dummy stage to follow the template guidelines
   - review
   - dast
   - staging
diff --git a/lib/gitlab/ci/templates/Chef.gitlab-ci.yml b/lib/gitlab/ci/templates/Chef.gitlab-ci.yml
index 33507aa58e4793f7bf790895b5c519e53ff4f102..1e14aa8bea94101de9941160cd2114d345f998ab 100644
--- a/lib/gitlab/ci/templates/Chef.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/Chef.gitlab-ci.yml
@@ -14,9 +14,11 @@ variables:
   KITCHEN_LOCAL_YAML: ".kitchen.dokken.yml"
 
 stages:
+  - build
   - lint
-  - unit
+  - test
   - functional
+  - deploy
 
 foodcritic:
   stage: lint
@@ -29,7 +31,7 @@ cookstyle:
   - chef exec cookstyle .
 
 chefspec:
-  stage: unit
+  stage: test
   script:
   - chef exec rspec spec
 
diff --git a/lib/gitlab/ci/templates/Go.gitlab-ci.yml b/lib/gitlab/ci/templates/Go.gitlab-ci.yml
index d572d7a1edc951712b0757e548f482e1e58cae14..55fda1a4799786b055b991d305d880ebf48183f9 100644
--- a/lib/gitlab/ci/templates/Go.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/Go.gitlab-ci.yml
@@ -18,6 +18,7 @@ before_script:
 stages:
     - test
     - build
+    - deploy
 
 format:
     stage: test
diff --git a/lib/gitlab/ci/templates/Mono.gitlab-ci.yml b/lib/gitlab/ci/templates/Mono.gitlab-ci.yml
index 86d62b93313b5c1712daeb57be108516eda19d63..10fb6be6c3936e34a17783b13ea923e039ad825b 100644
--- a/lib/gitlab/ci/templates/Mono.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/Mono.gitlab-ci.yml
@@ -15,6 +15,7 @@
 image: mono:latest
 
 stages:
+  - build
   - test
   - deploy
 
diff --git a/lib/gitlab/ci/templates/OpenShift.gitlab-ci.yml b/lib/gitlab/ci/templates/OpenShift.gitlab-ci.yml
index 290b9997084953e51a40961339661fb28469c80e..61a925e0d2dcd938dea160629baa1cd963bf5675 100644
--- a/lib/gitlab/ci/templates/OpenShift.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/OpenShift.gitlab-ci.yml
@@ -1,7 +1,9 @@
 image: ayufan/openshift-cli
 
 stages:
+  - build # dummy stage to follow the template guidelines
   - test
+  - deploy # dummy stage to follow the template guidelines
   - review
   - staging
   - production
diff --git a/lib/gitlab/ci/templates/Packer.gitlab-ci.yml b/lib/gitlab/ci/templates/Packer.gitlab-ci.yml
index fa296057c72b53e02a695833c58040269374d8bd..83e179f37c30bf4dfbea28082bff4eed5c8b6365 100644
--- a/lib/gitlab/ci/templates/Packer.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/Packer.gitlab-ci.yml
@@ -9,6 +9,8 @@ before_script:
 
 stages:
   - validate
+  - build
+  - test
   - deploy
 
 validate:
diff --git a/lib/gitlab/ci/templates/Serverless.gitlab-ci.yml b/lib/gitlab/ci/templates/Serverless.gitlab-ci.yml
index 4c92dcb7941f8ad8cf496bbb5e897c6fde068e9f..0fb7c57ab728517fa4fd7aacf78ea2af550c8d05 100644
--- a/lib/gitlab/ci/templates/Serverless.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/Serverless.gitlab-ci.yml
@@ -4,6 +4,7 @@ image: alpine:latest
 
 stages:
   - build
+  - test
   - deploy
 
 .serverless:build:image:
diff --git a/lib/gitlab/ci/templates/Swift.gitlab-ci.yml b/lib/gitlab/ci/templates/Swift.gitlab-ci.yml
index ba8a802ba4f80129c370fafc594b23f7482226b2..9aa4abd47912146254fd499dec36c0a43054f59e 100644
--- a/lib/gitlab/ci/templates/Swift.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/Swift.gitlab-ci.yml
@@ -2,7 +2,9 @@
 # This file assumes an own GitLab CI runner, setup on a macOS system.
 stages:
   - build
+  - test
   - archive
+  - deploy
 
 build_project:
   stage: build
diff --git a/lib/gitlab/ci/templates/Terraform.gitlab-ci.yml b/lib/gitlab/ci/templates/Terraform.gitlab-ci.yml
index 7160fce26a80cef033aabf9ddfb7a57238218790..f374bc7e26a80a77f2604e3f60fb7956193ec0a4 100644
--- a/lib/gitlab/ci/templates/Terraform.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/Terraform.gitlab-ci.yml
@@ -24,6 +24,7 @@ before_script:
 stages:
   - validate
   - build
+  - test
   - deploy
 
 validate:
diff --git a/lib/gitlab/ci/templates/iOS-Fastlane.gitlab-ci.yml b/lib/gitlab/ci/templates/iOS-Fastlane.gitlab-ci.yml
index df6ac4d340d3d30313dae6e83a49a44351cb2670..a4a9e96c1d25d833834a794def60a3fb62073c21 100644
--- a/lib/gitlab/ci/templates/iOS-Fastlane.gitlab-ci.yml
+++ b/lib/gitlab/ci/templates/iOS-Fastlane.gitlab-ci.yml
@@ -12,6 +12,8 @@
 
 stages:
   - build
+  - test
+  - deploy
 
 variables:
   LC_ALL: "en_US.UTF-8"
diff --git a/lib/gitlab/template/base_template.rb b/lib/gitlab/template/base_template.rb
index 0b4cc571dc058992c91c6e9f6cb45d4fe74a8751..14c9a3e0389db63dba2990b912797a87701d80e2 100644
--- a/lib/gitlab/template/base_template.rb
+++ b/lib/gitlab/template/base_template.rb
@@ -16,6 +16,12 @@ module Gitlab
       end
       alias_method :key, :name
 
+      def full_name
+        Pathname.new(@path)
+          .relative_path_from(self.class.base_dir)
+          .to_s
+      end
+
       def content
         @finder.read(@path)
       end
diff --git a/spec/lib/gitlab/ci/templates/templates_spec.rb b/spec/lib/gitlab/ci/templates/templates_spec.rb
index 4e3681cd943364361d39614ddc084e1550655e3e..b52064b303672cc7380f57c3537ad09d5fa2f08f 100644
--- a/spec/lib/gitlab/ci/templates/templates_spec.rb
+++ b/spec/lib/gitlab/ci/templates/templates_spec.rb
@@ -3,46 +3,32 @@
 require 'spec_helper'
 
 describe "CI YML Templates" do
-  ABSTRACT_TEMPLATES = %w[Serverless].freeze
-  # These templates depend on the presence of the `project`
-  # param to enable processing of `include:` within CI config.
-  PROJECT_DEPENDENT_TEMPLATES = %w[Auto-DevOps DAST].freeze
-
-  def self.concrete_templates
-    Gitlab::Template::GitlabCiYmlTemplate.all.reject do |template|
-      ABSTRACT_TEMPLATES.include?(template.name)
-    end
-  end
+  using RSpec::Parameterized::TableSyntax
 
-  def self.abstract_templates
-    Gitlab::Template::GitlabCiYmlTemplate.all.select do |template|
-      ABSTRACT_TEMPLATES.include?(template.name)
-    end
+  subject { Gitlab::Ci::YamlProcessor.new(content) }
+
+  where(:template_name) do
+    Gitlab::Template::GitlabCiYmlTemplate.all.map(&:full_name)
   end
 
-  describe 'concrete templates with CI/CD jobs' do
-    concrete_templates.each do |template|
-      it "#{template.name} template should be valid" do
-        # Trigger processing of included files
-        project = create(:project, :test_repo) if PROJECT_DEPENDENT_TEMPLATES.include?(template.name)
+  with_them do
+    let(:content) do
+      <<~EOS
+        include:
+          - template: #{template_name}
 
-        expect { Gitlab::Ci::YamlProcessor.new(template.content, project: project) }
-          .not_to raise_error
-      end
+        concrete_build_implemented_by_a_user:
+          stage: test
+          script: do something
+      EOS
+    end
+
+    it 'is valid' do
+      expect { subject }.not_to raise_error
     end
-  end
 
-  describe 'abstract templates without concrete jobs defined' do
-    abstract_templates.each do |template|
-      it "#{template.name} template should be valid after being implemented" do
-        content = template.content + <<~EOS
-          concrete_build_implemented_by_a_user:
-            stage: build
-            script: do something
-        EOS
-
-        expect { Gitlab::Ci::YamlProcessor.new(content) }.not_to raise_error
-      end
+    it 'require default stages to be included' do
+      expect(subject.stages).to include(*Gitlab::Ci::Config::Entry::Stages.default)
     end
   end
 end
diff --git a/spec/lib/gitlab/ci/yaml_processor_spec.rb b/spec/lib/gitlab/ci/yaml_processor_spec.rb
index b7b30e60d44c92820de17313d0ad7e121bfa61a4..0d998d89d739cc9a7a1a0cbb58be020d5fdded2d 100644
--- a/spec/lib/gitlab/ci/yaml_processor_spec.rb
+++ b/spec/lib/gitlab/ci/yaml_processor_spec.rb
@@ -615,19 +615,19 @@ module Gitlab
         subject { Gitlab::Ci::YamlProcessor.new(YAML.dump(config), opts) }
 
         context "when validating a ci config file with no project context" do
-          context "when a single string is provided", :quarantine do
+          context "when a single string is provided" do
             let(:include_content) { "/local.gitlab-ci.yml" }
 
-            it "does not return any error" do
-              expect { subject }.not_to raise_error
+            it "returns a validation error" do
+              expect { subject }.to raise_error /does not have project/
             end
           end
 
           context "when an array is provided" do
             let(:include_content) { ["/local.gitlab-ci.yml"] }
 
-            it "does not return any error" do
-              expect { subject }.not_to raise_error
+            it "returns a validation error" do
+              expect { subject }.to raise_error(Gitlab::Ci::YamlProcessor::ValidationError, /does not have project/)
             end
           end
 
@@ -643,11 +643,18 @@ module Gitlab
             let(:include_content) do
               [
                 'https://gitlab.com/awesome-project/raw/master/.before-script-template.yml',
-                '/templates/.after-script-template.yml',
                 { template: 'Auto-DevOps.gitlab-ci.yml' }
               ]
             end
 
+            before do
+              WebMock.stub_request(:get, 'https://gitlab.com/awesome-project/raw/master/.before-script-template.yml')
+                .to_return(
+                  status: 200,
+                  headers: { 'Content-Type' => 'application/json' },
+                  body: 'prepare: { script: ls -al }')
+            end
+
             it "does not return any error" do
               expect { subject }.not_to raise_error
             end