diff --git a/Dockerfile b/Dockerfile
index f2a30e65..f9de54bc 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -103,30 +103,10 @@ RUN set -x; \
 # Skins
 # The Minerva Neue, MonoBook, Timeless, Vector and Vector 2022 skins are bundled into MediaWiki and do not need to be
 # separately installed.
-RUN set -x; \
-	cd $MW_HOME/skins \
- 	# Chameleon (v. 4.2.1)
-  	&& git clone https://github.com/ProfessionalWiki/chameleon $MW_HOME/skins/chameleon \
-	&& cd $MW_HOME/skins/chameleon \
-	&& git checkout -q f34a56528ada14ac07e1b03beda41f775ef27606 \
-	# CologneBlue
-	&& git clone -b $MW_VERSION --single-branch https://github.com/wikimedia/mediawiki-skins-CologneBlue $MW_HOME/skins/CologneBlue \
-	&& cd $MW_HOME/skins/CologneBlue \
-	&& git checkout -q 4d588eb78d7e64e574f631c5897579537305437d \
-	# Modern
-	&& git clone -b $MW_VERSION --single-branch https://github.com/wikimedia/mediawiki-skins-Modern $MW_HOME/skins/Modern \
-	&& cd $MW_HOME/skins/Modern \
-	&& git checkout -q fb6c2831b5f150e9b82d98d661710695a2d0f8f2 \
-	# Pivot
-	&& git clone -b v2.3.0 https://github.com/wikimedia/mediawiki-skins-Pivot $MW_HOME/skins/pivot \
-	&& cd $MW_HOME/skins/pivot \
-	&& git checkout -q d79af7514347eb5272936243d4013118354c85c1 \
-	# Refreshed
-	&& git clone -b $MW_VERSION --single-branch https://github.com/wikimedia/mediawiki-skins-Refreshed $MW_HOME/skins/Refreshed \
-	&& cd $MW_HOME/skins/Refreshed \
-	&& git checkout -q 86f33620f25335eb62289aa18d342ff3b980d8b8
-
+COPY _sources/scripts/extensions-skins.php /tmp/extensions-skins.php
 COPY _sources/patches/* /tmp/
+COPY _sources/configs/skins.yaml /tmp/skins.yaml
+RUN php /tmp/extensions-skins.php "skins" "/tmp/skins.yaml"
 
 # Extensions
 # The following extensions are bundled into MediaWiki and do not need to be separately installed:
@@ -136,16 +116,8 @@ COPY _sources/patches/* /tmp/
 # VisualEditor, WikiEditor.
 # The following extensions are downloaded via Composer and also do not need to be downloaded here:
 # Bootstrap, DataValues (and related extensions like DataValuesCommon), ParserHooks.
-COPY _sources/scripts/extension-setup.sh /tmp/extension-setup.sh
 COPY _sources/configs/extensions.yaml /tmp/extensions.yaml
-RUN wget -qO /usr/local/bin/yq https://github.com/mikefarah/yq/releases/latest/download/yq_linux_amd64
-RUN chmod a+x /usr/local/bin/yq
-RUN set -x; \
-	apt-get update \
-	&& apt-get install -y jq \
-	&& chmod +x /tmp/extension-setup.sh 
-
-RUN /tmp/extension-setup.sh
+RUN php /tmp/extensions-skins.php "extensions" "/tmp/extensions.yaml"
 
 # Patch composer
 RUN set -x; \
diff --git a/_sources/configs/skins.yaml b/_sources/configs/skins.yaml
new file mode 100644
index 00000000..d7a76703
--- /dev/null
+++ b/_sources/configs/skins.yaml
@@ -0,0 +1,17 @@
+# Canasta YAML file for skins for MediaWiki 1.39.
+# Where the repository is not specified, the Wikimedia Git repository for the
+# skins with that name is used, and the default branch used is REL1_39.
+# Where the repository *is* specified, the default branch used is master.
+skins:
+  - Chameleon:
+      commit: f34a56528ada14ac07e1b03beda41f775ef27606 # v. 4.2.1
+      repository: https://github.com/ProfessionalWiki/chameleon
+  - CologneBlue:
+      commit: 4d588eb78d7e64e574f631c5897579537305437d
+  - Modern:
+      commit: fb6c2831b5f150e9b82d98d661710695a2d0f8f2
+  - Pivot:
+      branch: v2.3.0
+      commit: d79af7514347eb5272936243d4013118354c85c1
+  - Refreshed:
+      commit: 86f33620f25335eb62289aa18d342ff3b980d8b8
\ No newline at end of file
diff --git a/_sources/scripts/extension-setup.sh b/_sources/scripts/extension-setup.sh
deleted file mode 100644
index e8671423..00000000
--- a/_sources/scripts/extension-setup.sh
+++ /dev/null
@@ -1,30 +0,0 @@
-#!/bin/bash
-
-MW_HOME="$MW_HOME"
-MW_VERSION="$MW_VERSION"
-# Since yq cannot process data from variables, a conversion is made to JSON format to utilise jq.
-commands=$(yq eval '. | to_json' /tmp/extensions.yaml)
-echo "$commands" | jq -r '.extensions' | jq -c '.[]' | while read -r obj; do
-    extension_data=$(echo "$obj" | jq -r 'keys_unsorted[] as $key | select(has($key)) | "\($key) \(.[$key].repository) \(.[$key].commit) \(.[$key].branch)"')
-    read -r extension_name repository commit branch <<< "$extension_data"
-    
-    git_clone_cmd="git clone "
-    if [ "$repository" == "null" ]; then
-        repository="https://github.com/wikimedia/mediawiki-extensions-$extension_name" 
-        if [ "$branch" == "null" ]; then
-            branch=$MW_VERSION
-            git_clone_cmd="$git_clone_cmd --single-branch -b $branch"    
-        fi
-    fi
-    git_clone_cmd="$git_clone_cmd $repository $MW_HOME/extensions/$extension_name"
-    git_checkout_cmd="cd $MW_HOME/extensions/$extension_name && git checkout -q $commit"
-
-    eval "$git_clone_cmd && $git_checkout_cmd"
-    patches=$(echo "$obj" | jq -r ".$extension_name.patches")
-    if [ "$patches" != "null" ]; then
-        echo "$patches" | jq -c '.[]' | while read -r patch; do
-            git_apply_cmd="cd $MW_HOME/extensions/$extension_name && git apply /tmp/$patch"
-            eval "$git_apply_cmd"
-        done
-    fi
-done
diff --git a/_sources/scripts/extensions-skins.php b/_sources/scripts/extensions-skins.php
new file mode 100644
index 00000000..0d57dac2
--- /dev/null
+++ b/_sources/scripts/extensions-skins.php
@@ -0,0 +1,47 @@
+<!-- It is much easier to do parsing of YAML in PHP than in .sh; the standard way to do YAML parsing
+in a shell script is to call yq, but yq requires different executables for different architectures. 
+Given that the YAML parsing is already in PHP, it seemed easier to do the whole thing in PHP rather 
+than split the work between two scripts -->
+<?php
+
+$MW_HOME = getenv("MW_HOME");
+$MW_VERSION = getenv("MW_VERSION");
+$type = $argv[1];
+$path = $argv[2];
+
+$yamlData = yaml_parse_file($path);
+
+foreach ($yamlData[$type] as $obj) {
+    $name = key($obj);
+    $data = $obj[$name];
+    
+    $repository = $data['repository'] ?? null;
+    $commit = $data['commit'] ?? null;
+    $branch = $data['branch'] ?? null;
+    $patches = $data['patches'] ?? null;
+    
+    $gitCloneCmd = "git clone ";
+    
+    if ($repository === null) {
+        $repository = "https://github.com/wikimedia/mediawiki-$type-$name";
+        if ($branch === null) {
+            $branch = $MW_VERSION;
+            $gitCloneCmd .= "--single-branch -b $branch ";
+        }
+    }
+    
+    $gitCloneCmd .= "$repository $MW_HOME/$type/$name";
+    $gitCheckoutCmd = "cd $MW_HOME/$type/$name && git checkout -q $commit";
+
+    exec($gitCloneCmd);
+    exec($gitCheckoutCmd);
+
+    if ($patches !== null) {
+        foreach ($patches as $patch) {
+            $gitApplyCmd = "cd $MW_HOME/$type/$name && git apply /tmp/$patch";
+            exec($gitApplyCmd);
+        }
+    }
+}
+
+?>