diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 671e08a00..c9b60f1e0 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -21,7 +21,7 @@ repos:
 #        args: [--target-version, "2.2"]
 
   - repo: https://github.com/PyCQA/flake8
-    rev: 7.3.0
+    rev: 7.0.0
     hooks:
       - id: flake8
         entry: pflake8
diff --git a/pyproject.toml b/pyproject.toml
index 33333a085..554b17ce0 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -19,6 +19,13 @@ dependencies = [
     "django>=3.2",
     "django-polymorphic",
     "easy-thumbnails[svg]",
+    
+    # Pin svglib to a version below 1.6.0.
+    # The latest version (1.6.0) adds pycairo as a dependency,
+    # which requires system-level libraries and fails to install in the container.
+    # This can be removed once the issue is resolved.
+    # See: https://github.com/deeplook/svglib/issues/421
+    "svglib~=1.5.1"
 ]
 classifiers = [
     "Development Status :: 5 - Production/Stable",