paulbalandan · Nov 3, 2026 · Nov 3, 2026 · Nov 3, 2026
diff --git a/.github/carson.yml b/.github/carson.yml
@@ -22,7 +22,7 @@ settings:
         files: ['.github/workflows/*']
       - label: documentation
         files:
-          all: ['user_guide_src/source/**']
+          all: ['docs/**']
       - label: testing
         files:
           all: ['tests/**']

diff --git a/.github/dependabot.yml b/.github/dependabot.yml
@@ -24,3 +24,12 @@ updates:
         patterns:
           - '*'
         group-by: dependency-name
+
+  - package-ecosystem: 'pip'
+    directory: '/docs'
+    schedule:
+      interval: 'weekly'
+    groups:
+      user-guide-dependencies:
+        patterns:
+          - '*'
diff --git a/.github/instructions/user-guide.instructions.md b/.github/instructions/user-guide.instructions.md
@@ -1,11 +1,15 @@
 ---
-applyTo: "user_guide_src/**/*.rst"
+applyTo: "docs/**/*.md"
 ---
 
 # User guide
 
-- Preserve the existing reStructuredText structure, terminology, directives,
+- Preserve the existing Markdown structure, terminology, admonitions,
   anchors, and surrounding writing style.
+- Indent nested lists and admonition bodies by four spaces, and keep the two
+  trailing spaces that end a line as a hard line break.
+- Add a new page to the page's folder `index.md` and run
+  `php admin/update-docs-nav.php` to add it to `docs/.nav.yml`.
 - Keep PHP examples compatible with PHP 8.2 and verify signatures and behavior
   against the current framework code.
 - Distinguish new behavior from existing behavior and document defaults
@@ -22,6 +26,6 @@ applyTo: "user_guide_src/**/*.rst"
   smallest migration in both the minor changelog and upgrading guide.
 - Keep code examples minimal but complete enough to run in a normal
   CodeIgniter application.
-- Leave the complete Sphinx build and documentation validation to GitHub
+- Leave the complete MkDocs build and documentation validation to GitHub
   Actions unless the task specifically requires local documentation
   validation.
diff --git a/.github/instructions/worker-mode.instructions.md b/.github/instructions/worker-mode.instructions.md
@@ -1,5 +1,5 @@
 ---
-applyTo: "system/Boot.php,system/CodeIgniter.php,system/Commands/Worker/**,system/Config/BaseService.php,system/Config/Factories.php,system/Config/Factory.php,system/Config/Services.php,system/Database/Config.php,system/Database/BaseConnection.php,system/Database/ConnectionInterface.php,system/Database/*/Connection.php,system/Events/Events.php,system/Session/**,system/Cache/**,system/HTTP/**,system/Filters/**,system/Router/**,system/Security/**,system/Debug/Toolbar.php,system/Debug/Toolbar/**,app/Config/WorkerMode.php,tests/system/Commands/Worker/**,user_guide_src/source/installation/worker_mode.rst"
+applyTo: "system/Boot.php,system/CodeIgniter.php,system/Commands/Worker/**,system/Config/BaseService.php,system/Config/Factories.php,system/Config/Factory.php,system/Config/Services.php,system/Database/Config.php,system/Database/BaseConnection.php,system/Database/ConnectionInterface.php,system/Database/*/Connection.php,system/Events/Events.php,system/Session/**,system/Cache/**,system/HTTP/**,system/Filters/**,system/Router/**,system/Security/**,system/Debug/Toolbar.php,system/Debug/Toolbar/**,app/Config/WorkerMode.php,tests/system/Commands/Worker/**,docs/installation/worker_mode.md"
 ---
 
 # FrankenPHP Worker Mode

diff --git a/.github/skills/forum-announcement/SKILL.md b/.github/skills/forum-announcement/SKILL.md
@@ -25,7 +25,7 @@ Create a forum-ready CodeIgniter4 release announcement using myBB markup.
 
 ## Procedure
 1. Read `CHANGELOG.md` for release summary and PR references.
-2. Read `user_guide_src/source/changelogs/v{VERSION}.rst` for each target version.
+2. Read `docs/changelogs/v{VERSION}.md` for each target version.
 3. Determine release mode:
     - Single release: one `4.x.y` version.
     - Dual release: maintenance + major; maintenance is presented first in the post.

diff --git a/.gitignore b/.gitignore
@@ -42,11 +42,18 @@ $RECYCLE.BIN/
 # These should never be under version control,
 # as it poses a security risk.
 .env
-.vagrant
-Vagrantfile
-/user_guide_src/venv/
+
+#-------------------------
+# Local Configuration
+#-------------------------
+# phpenv local config
+.php-version
+
+# pyenv local config
 .python-version
-/user_guide_src/.python-version
+
+/phpunit.xml
+/.php-cs-fixer.php
 
 #-------------------------
 # Temporary Files
@@ -72,21 +79,19 @@ Vagrantfile
 php_errors.log
 
 #-------------------------
-# User Guide Temp Files
+# Build Output
 #-------------------------
-/user_guide_src/build/*
+# Test coverage
+/build/
+
+# phpDocumentor
+/api/
+
+# User guide
 /site/
 /venv/
 __pycache__/
 
-#-------------------------
-# Test Files
-#-------------------------
-/tests/coverage*
-
-# Don't save phpunit under version control.
-/phpunit
-
 #-------------------------
 # Composer
 #-------------------------
@@ -97,21 +102,13 @@ composer.lock
 # IDE / Development Files
 #-------------------------
 
-# Modules Testing
-_modules/*
-
-# phpenv local config
-.php-version
-
 # Jetbrains editors (PHPStorm, etc)
 .idea/
 *.iml
 
 # Netbeans
 /nbproject/
-/build/
 /nbbuild/
-/dist/
 /nbdist/
 /nbactions.xml
 /nb-configuration.xml
@@ -124,12 +121,6 @@ _modules/*
 *.sublime-workspace
 *.sublime-project
 .phpintel
-/api/
 
 # Visual Studio Code
 .vscode/
-
-/results/
-/phpunit.xml
-
-/.php-cs-fixer.php
diff --git a/README.md b/README.md
@@ -26,7 +26,7 @@ More information about the plans for version 4 can be found in [CodeIgniter 4](h
 
 The [User Guide](https://codeigniter.com/user_guide/) is the primary documentation for CodeIgniter 4.
 
-You will also find the [current **in-progress** User Guide](https://codeigniter4.github.io/CodeIgniter4/).
+You will also find the [current **in-progress** User Guide](https://codeigniter4.github.io/CodeIgniter4/develop/).
 As with the rest of the framework, it is a work in progress, and will see changes over time to structure, explanations, etc.
 
 You might also be interested in the [API documentation](https://codeigniter4.github.io/api/) for the framework components.

diff --git a/admin/framework/.gitignore b/admin/framework/.gitignore
@@ -42,8 +42,14 @@ $RECYCLE.BIN/
 # These should never be under version control,
 # as it poses a security risk.
 .env
-.vagrant
-Vagrantfile
+
+#-------------------------
+# Local Configuration
+#-------------------------
+# phpenv local config
+.php-version
+
+/phpunit.xml
 
 #-------------------------
 # Temporary Files
@@ -66,20 +72,13 @@ Vagrantfile
 php_errors.log
 
 #-------------------------
-# User Guide Temp Files
-#-------------------------
-/user_guide_src/build/*
-/user_guide_src/cilexer/build/*
-/user_guide_src/cilexer/dist/*
-/user_guide_src/cilexer/pycilexer.egg-info/*
-
-#-------------------------
-# Test Files
+# Build Output
 #-------------------------
-/tests/coverage*
+# Test coverage
+/build/
 
-# Don't save phpunit under version control.
-/phpunit
+# phpDocumentor
+/api/
 
 #-------------------------
 # Composer
@@ -90,21 +89,13 @@ vendor/
 # IDE / Development Files
 #-------------------------
 
-# Modules Testing
-_modules/*
-
-# phpenv local config
-.php-version
-
 # Jetbrains editors (PHPStorm, etc)
 .idea/
 *.iml
 
 # NetBeans
 /nbproject/
-/build/
 /nbbuild/
-/dist/
 /nbdist/
 /nbactions.xml
 /nb-configuration.xml
@@ -117,10 +108,6 @@ _modules/*
 *.sublime-workspace
 *.sublime-project
 .phpintel
-/api/
 
 # Visual Studio Code
 .vscode/
-
-/results/
-/phpunit.xml
diff --git a/admin/starter/.gitignore b/admin/starter/.gitignore
@@ -42,8 +42,14 @@ $RECYCLE.BIN/
 # These should never be under version control,
 # as it poses a security risk.
 .env
-.vagrant
-Vagrantfile
+
+#-------------------------
+# Local Configuration
+#-------------------------
+# phpenv local config
+.php-version
+
+/phpunit.xml
 
 #-------------------------
 # Temporary Files
@@ -66,20 +72,13 @@ Vagrantfile
 php_errors.log
 
 #-------------------------
-# User Guide Temp Files
-#-------------------------
-/user_guide_src/build/*
-/user_guide_src/cilexer/build/*
-/user_guide_src/cilexer/dist/*
-/user_guide_src/cilexer/pycilexer.egg-info/*
-
-#-------------------------
-# Test Files
+# Build Output
 #-------------------------
-/tests/coverage*
+# Test coverage
+/build/
 
-# Don't save phpunit under version control.
-/phpunit
+# phpDocumentor
+/api/
 
 #-------------------------
 # Composer
@@ -90,21 +89,13 @@ vendor/
 # IDE / Development Files
 #-------------------------
 
-# Modules Testing
-_modules/*
-
-# phpenv local config
-.php-version
-
 # Jetbrains editors (PHPStorm, etc)
 .idea/
 *.iml
 
 # NetBeans
 /nbproject/
-/build/
 /nbbuild/
-/dist/
 /nbdist/
 /nbactions.xml
 /nb-configuration.xml
@@ -117,10 +108,6 @@ _modules/*
 *.sublime-workspace
 *.sublime-project
 .phpintel
-/api/
 
 # Visual Studio Code
 .vscode/
-
-/results/
-/phpunit.xml
diff --git a/admin/userguide/.gitignore b/admin/userguide/.gitignore
@@ -5,9 +5,4 @@
 !*/cache/index.html
 !*/cache/.htaccess
 
-user_guide_src/build/*
-user_guide_src/cilexer/build/*
-user_guide_src/cilexer/dist/*
-user_guide_src/cilexer/pycilexer.egg-info/*
-
 /vendor/
diff --git a/contributing/ELDocs.tmbundle.zip b/contributing/ELDocs.tmbundle.zip