diff --git a/README.md b/README.md
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+++ b/README.md
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+# WDS Headless SEO
+
+Please see <https://webdevstudios.github.io/nextjs-wordpress-starter/> for more information.
diff --git a/activation.php b/activation.php
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+++ b/activation.php
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+<?php
+/**
+ * Plugin activation functionality.
+ *
+ * @author WebDevStudios
+ * @package WDS_Headless_SEO
+ * @since 1.0.0
+ */
+
+namespace WDS_Headless_SEO;
+
+/**
+ * Plugin activation callback.
+ *
+ * @author WebDevStudios
+ * @since 1.0.0
+ */
+function activation_callback() {
+	do_action( 'wds_headless_seo_activate' );
+
+	// Save current plugin version.
+	update_option( 'wds_headless_seo_version', WDS_HEADLESS_SEO_VERSION );
+}
diff --git a/composer.json b/composer.json
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+++ b/composer.json
@@ -0,0 +1,13 @@
+{
+  "name": "webdevstudios/wds-headless-seo",
+  "description": "WDS Headless extension handling SEO functionality.",
+  "homepage": "https://github.com/WebDevStudios/nextjs-wordpress-starter",
+  "type": "wordpress-plugin",
+  "license": "GPL-2.0-or-later",
+  "authors": [
+    {
+      "name": "WebDevStudios",
+      "email": "contact@webdevstudios.com"
+    }
+  ]
+}
diff --git a/deactivation.php b/deactivation.php
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+++ b/deactivation.php
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+<?php
+/**
+ * Plugin deactivation functionality.
+ *
+ * @author WebDevStudios
+ * @package WDS_Headless_SEO
+ * @since 1.0.0
+ */
+
+namespace WDS_Headless_SEO;
+
+/**
+ * Plugin deactivation callback.
+ *
+ * @author WebDevStudios
+ * @since 1.0.0
+ */
+function deactivation_callback() {
+	do_action( 'wds_headless_seo_deactivate' );
+
+	// Delete plugin version.
+	delete_option( 'wds_headless_seo_version' );
+}
diff --git a/inc/links.php b/inc/links.php
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--- /dev/null
+++ b/inc/links.php
@@ -0,0 +1,43 @@
+<?php
+/**
+ * Link/redirection functionality.
+ *
+ * @author WebDevStudios
+ * @package WDS_Headless_SEO
+ * @since 1.0.0
+ */
+
+namespace WDS_Headless_SEO;
+
+if ( ! defined( 'WPSEO_VERSION' ) ) {
+	return;
+}
+
+/**
+ * Replace Site URL JAMStack URL as needed.
+ *
+ * @author WebDevStudios
+ * @since  1.0.0
+ * @param  array $breadcrumbs Yoast SEO breadcrumbs.
+ * @return array              Filtered breadcrumbs.
+ */
+function breadcrumb_links( array $breadcrumbs ) {
+	if ( ! defined( 'HEADLESS_FRONTEND_URL' ) ) {
+		return $breadcrumbs;
+	}
+
+	$base_url = rtrim( HEADLESS_FRONTEND_URL, '/' );
+
+	// Override domain in breadcrumbs.
+	return array_map(
+		function( $breadcrumb ) use ( $base_url ) {
+			$parsed_url        = wp_parse_url( $breadcrumb['url'] );
+			$path              = $parsed_url['path'] ?? '';
+			$breadcrumb['url'] = "{$base_url}{$path}";
+
+			return $breadcrumb;
+		},
+		$breadcrumbs
+	);
+}
+add_filter( 'wpseo_breadcrumb_links', __NAMESPACE__ . '\breadcrumb_links' );
diff --git a/inc/wp-graphql.php b/inc/wp-graphql.php
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--- /dev/null
+++ b/inc/wp-graphql.php
@@ -0,0 +1,101 @@
+<?php
+/**
+ * WP GraphQL settings.
+ *
+ * @see https://wordpress.org/plugins/wp-graphql/
+ * @author WebDevStudios
+ * @package WDS_Headless_SEO
+ * @since 1.0.0
+ */
+
+namespace WDS_Headless_SEO;
+
+use WPSEO_Options;
+
+/**
+ * Add archive SEO field to CPT archive queries in GraphQL.
+ *
+ * @author WebDevStudios
+ * @since 1.0.0
+ * @return void
+ */
+function register_archive_seo() {
+	if ( ! class_exists( 'WPSEO_Options' ) ) {
+		return;
+	}
+
+	register_graphql_object_type(
+		'ArchiveSeo',
+		[
+			'description' => esc_html__( 'Archive SEO data', 'wds-headless-seo' ),
+			'fields'      => [
+				'title'              => [ 'type' => 'String' ],
+				'metaDesc'           => [ 'type' => 'String' ],
+				'metaRobotsNoindex'  => [ 'type' => 'String' ],
+				'metaRobotsNofollow' => [ 'type' => 'String' ],
+				'canonical'          => [ 'type' => 'String' ],
+			],
+		]
+	);
+
+	// Get post types that support archives (will not include "post" PT).
+	$post_types = get_post_types(
+		[
+			'has_archive' => true,
+		],
+		'objects'
+	);
+
+	// Bail if we don't have an array of post types.
+	if ( empty( $post_types ) || ! is_array( $post_types ) ) {
+		return;
+	}
+
+	// Register GraphQL field on each post type's plural/archive connection.
+	foreach ( $post_types as $post_type => $post_type_object ) {
+		if ( ! $post_type_object->show_in_graphql || ! $post_type_object->graphql_single_name ) {
+			break;
+		}
+
+		$pt_singular = ucfirst( $post_type_object->graphql_single_name );
+
+		register_graphql_field(
+			"RootQueryTo{$pt_singular}Connection",
+			'archiveSeo',
+			[
+				'type'        => 'ArchiveSeo',
+				'description' => sprintf(
+					/* translators: the post type label. */
+					__( 'The Yoast SEO data of the %s post type archive', 'wds-headless-seo' ),
+					$post_type_object->label
+				),
+				'resolve'     => function () use ( $post_type, $post_type_object ) {
+					// Surface info: https://developer.yoast.com/blog/yoast-seo-14-0-using-yoast-seo-surfaces/.
+					/* We would ideally use this surface to determine meta title and desc, but the surface is not pulling the correct meta for those fields (as of Yoast 15.9.2, it seems to be pulling some default archive meta title and a blank desc). */
+					$archive_seo = YoastSEO()->meta->for_post_type_archive( $post_type );
+
+					// Retrieve Yoast SEO options for archive title and desc instead.
+					$wpseo_options = WPSEO_Options::get_instance();
+					$title         = $wpseo_options->get( "title-ptarchive-{$post_type}" );
+					$description   = $wpseo_options->get( "metadesc-ptarchive-{$post_type}", $archive_seo->description );
+
+					/* Manually replace title vars that won't get caught in next step (e.g., pt_single, pt_plural) -- these appear to be "advanced" vars that require a single post to be passed, rather than a post type object. */
+					$title = str_ireplace( '%%pt_single%%', $post_type_object->labels->singular_name, $title );
+					$title = str_ireplace( '%%pt_plural%%', $post_type_object->labels->name, $title );
+
+					// Replace standard title vars with post type object.
+					$title = wpseo_replace_vars( $title, $post_type_object );
+
+					return [
+						'title'              => wp_gql_seo_format_string( $title ?? $archive_seo->title ),
+						'metaDesc'           => wp_gql_seo_format_string( $description ),
+						'metaRobotsNoindex'  => $archive_seo->robots['index'],
+						'metaRobotsNofollow' => $archive_seo->robots['follow'],
+						'canonical'          => $archive_seo->canonical,
+					];
+				},
+			]
+		);
+	}
+}
+add_action( 'graphql_register_types', __NAMESPACE__ . '\register_archive_seo' );
diff --git a/wds-headless-seo.php b/wds-headless-seo.php
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--- /dev/null
+++ b/wds-headless-seo.php
@@ -0,0 +1,33 @@
+<?php
+/**
+ * Plugin Name: WDS Headless (SEO)
+ * Plugin URI: https://github.com/WebDevStudios/nextjs-wordpress-starter
+ * Description: WDS Headless extension handling SEO functionality.
+ * Author: WebDevStudios <contact@webdevstudios.com>
+ * Author URI: https://webdevstudios.com
+ * Version: 1.0.0
+ * Requires at least: 5.6
+ * Requires PHP: 7.4
+ * License: GPL-2
+ * License URI: https://www.gnu.org/licenses/gpl-2.0.html
+ *
+ * @package WDS_Headless_SEO
+ */
+
+namespace WDS_Headless_SEO;
+
+if ( ! defined( 'ABSPATH' ) ) {
+	return;
+}
+
+// Define constants.
+define( 'WDS_HEADLESS_SEO_PLUGIN_DIR', plugin_dir_path( __FILE__ ) );
+define( 'WDS_HEADLESS_SEO_PLUGIN_URL', plugin_dir_url( __FILE__ ) );
+define( 'WDS_HEADLESS_SEO_VERSION', '1.0.0' );
+
+// Register de/activation hooks.
+register_activation_hook( __FILE__, __NAMESPACE__ . '\activation_callback' );
+register_deactivation_hook( __FILE__, __NAMESPACE__ . '\deactivation_callback' );
+
+require_once 'inc/links.php';
+require_once 'inc/wp-graphql.php';