diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..6cbc618
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,12 @@
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+indent_style = space
+indent_size = 2
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.php]
+indent_size = 4
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
new file mode 100644
index 0000000..a52dbb2
--- /dev/null
+++ b/.pre-commit-config.yaml
@@ -0,0 +1,10 @@
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v3.3.0
+    hooks:
+      - id: fix-byte-order-marker
+      - id: end-of-file-fixer
+      - id: trailing-whitespace
+
+      - id: mixed-line-ending
+        args: [--fix=lf]
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..65c7ac0
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,14 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
+and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## 1.0.0 - 2020-12-03
+
+- Initial release.
+
+[Unreleased]: https://github.com/Calinou/q2a-prefill-fields/compare/v1.0.0...HEAD
diff --git a/LICENSE.md b/LICENSE.md
new file mode 100644
index 0000000..149ba76
--- /dev/null
+++ b/LICENSE.md
@@ -0,0 +1,21 @@
+# MIT License
+
+Copyright © 2020 Hugo Locurcio and contributors
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..d05482d
--- /dev/null
+++ b/README.md
@@ -0,0 +1,47 @@
+# Pre-fill form fields for Question2Answer
+
+A Question2Answer plugin to pre-fill form fields on the *Ask a question* page
+using GET parameters.
+
+## Features
+
+Supported fields are:
+
+- `title`
+- `content` **(only when not using a rich/WYSIWYG editor)**
+- `tags`
+
+Since the user can input arbitrary values as GET parameters, the values are
+escaped using PHP's `htmlspecialchars()` function. You can use multiple tags by
+separating each tag with a `+` or `%20` in the URL.
+
+## Example
+
+The following URL, when entered in the browser address bar:
+
+```text
+http://localhost:8000/index.php?qa=ask&title=Hello+world&content=something&tags=one%20two%20three
+```
+
+Will result in:
+
+- **Title:** Hello world
+- **Content:** something
+- **Tags:** one two three *(as 3 separate tags, since Q2A separates tags with spaces)*
+
+## Installation
+
+- Clone this repository or
+  [download a ZIP archive](https://github.com/Calinou/q2a-prefill-fields/archive/master.zip).
+- Move the extracted folder to the `qa-plugin/` folder of your Question2Answer
+  installation.
+- Log in as administrator on your Question2Answer instance, navigate to
+  **Admin > Plugins** and make sure the **Prefill Fields** plugin is visible
+  and enabled.
+
+## License
+
+Copyright © 2020 Hugo Locurcio and contributors
+
+Unless otherwise specified, files in this repository are licensed under the
+MIT license. See [LICENSE.md](LICENSE.md) for more information.
diff --git a/qa-plugin.php b/qa-plugin.php
new file mode 100644
index 0000000..bf45f85
--- /dev/null
+++ b/qa-plugin.php
@@ -0,0 +1,40 @@
+<?php
+// Copyright © 2020 Hugo Locurcio and contributors
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+/*
+    Plugin Name: Prefill Fields
+    Plugin URI: https://github.com/Calinou/q2a-prefill-fields
+    Plugin Description: Allows prefilling question fields (title, content and tags) using GET parameters
+    Plugin Version: 1.0.0
+    Plugin Date: 2020-12-03
+    Plugin Author: Hugo Locurcio
+    Plugin Author URI: https://hugo.pro/
+    Plugin License: MIT
+    Plugin Minimum Question2Answer Version: 1.8
+    Plugin Update Check URI: https://raw.githubusercontent.com/Calinou/q2a-prefill-fields/master/qa-plugin.php
+*/
+
+// Don't allow this page to be requested directly from browser.
+if (!defined('QA_VERSION')) {
+    header('Location: ../../');
+    exit;
+}
+
+qa_register_plugin_layer('qa-prefill-fields-layer.php', 'Prefill Fields Layer');
diff --git a/qa-prefill-fields-layer.php b/qa-prefill-fields-layer.php
new file mode 100644
index 0000000..ce337b8
--- /dev/null
+++ b/qa-prefill-fields-layer.php
@@ -0,0 +1,57 @@
+<?php
+// Copyright © 2020 Hugo Locurcio and contributors
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+class qa_html_theme_layer extends qa_html_theme_base
+{
+    /**
+     * Adds the required JavaScript code to prefill question fields on the "Ask
+     * a question" page.
+     *
+     * Supported GET parameters are `title`, `content` and `tags`.
+     * NOTE: `content` prefilling only works if a rich/WYSIWYG editor is *not* in use!
+     *       Otherwise, the rich editor's loading will override the field's contents.
+     */
+    public function head_script()
+    {
+        if ($this->template === 'ask') {
+            $this->content['script'][] = '<script>
+            window.addEventListener("DOMContentLoaded", () => {
+                const titleField = document.querySelector("input[name=\'title\']");
+                if (titleField) {
+                    titleField.value = "' . htmlspecialchars($_GET['title']) . '";
+                }
+
+                const contentField = document.querySelector("input[name=\'content\']");
+                if (contentField) {
+                    contentField.value = "' . htmlspecialchars($_GET['content']) . '";
+                }
+
+                const tagsField = document.querySelector("input[name=\'tags\']");
+                if (tagsField) {
+                    tagsField.value = "' . htmlspecialchars($_GET['tags']) . '";
+                }
+            });
+            </script>';
+        }
+
+        parent::head_script();
+    }
+}