diff --git a/.github/workflows/test-extensions.yml b/.github/workflows/test-extensions.yml
index b57497c..1304de2 100644
--- a/.github/workflows/test-extensions.yml
+++ b/.github/workflows/test-extensions.yml
@@ -4,6 +4,20 @@ on:
   - pull_request
 
 jobs:
+  check_syntax_data:
+    name: Check data syntax
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Check order supported extensions list
+        run: |
+          sort -o data/supported-extensions.sorted data/supported-extensions
+          if ! DIFF="$(diff -u data/supported-extensions data/supported-extensions.sorted)"; then
+            printf 'The order of extensions in data/supported-extensions is wrong.\nThe list of required changes is:\n\n%s\n' "$DIFF" >&2
+            exit 1
+          fi
+          rm data/supported-extensions.sorted
   check_syntax_shell:
     name: Check shell coding style
     runs-on: ubuntu-latest
@@ -41,6 +55,7 @@ jobs:
         run: composer run-script lint -- --dry-run --diff
   test_extensions:
     needs:
+      - check_syntax_data
       - check_syntax_shell
       - check_syntax_php
     strategy:
@@ -67,6 +82,7 @@ jobs:
   test_restoring_packages:
     name: Test restoring packages
     needs:
+      - check_syntax_data
       - check_syntax_shell
       - check_syntax_php
     runs-on: ubuntu-latest
@@ -79,6 +95,7 @@ jobs:
   test_custom_version:
     name: Test installing specific versions
     needs:
+      - check_syntax_data
       - check_syntax_shell
       - check_syntax_php
     runs-on: ubuntu-latest
diff --git a/data/supported-extensions b/data/supported-extensions
index f24f0cb..4bf138e 100644
--- a/data/supported-extensions
+++ b/data/supported-extensions
@@ -56,8 +56,8 @@ rdkafka 5.5 5.6 7.0 7.1 7.2 7.3 7.4
 recode 5.5 5.6 7.0 7.1 7.2 7.3
 redis 5.5 5.6 7.0 7.1 7.2 7.3 7.4 8.0
 shmop 5.5 5.6 7.0 7.1 7.2 7.3 7.4 8.0
-snuffleupagus 7.0 7.1 7.2 7.3 7.4
 snmp 5.5 5.6 7.0 7.1 7.2 7.3 7.4 8.0
+snuffleupagus 7.0 7.1 7.2 7.3 7.4
 soap 5.5 5.6 7.0 7.1 7.2 7.3 7.4 8.0
 sockets 5.5 5.6 7.0 7.1 7.2 7.3 7.4 8.0
 solr 5.5 5.6 7.0 7.1 7.2 7.3 7.4 8.0