diff --git a/dev_scripts/env.py b/dev_scripts/env.py
index bb2b1fa..7f45a52 100755
--- a/dev_scripts/env.py
+++ b/dev_scripts/env.py
@@ -17,6 +17,7 @@ DEFAULT_DEV = False
 DEFAULT_SHOW_DOCKERFILE = False
 DEFAULT_DOWNLOAD_PYSIDE6 = False
 
+PYSIDE6_VERSION = "6.6.3.1"
 PYSIDE6_RPM = "python3-pyside6-{pyside6_version}-1.fc{fedora_version}.x86_64.rpm"
 PYSIDE6_URL = (
     "https://packages.freedom.press/yum-tools-prod/dangerzone/f{fedora_version}/%s"
@@ -309,8 +310,8 @@ class PySide6Manager:
     """Provision PySide6 RPMs in our Dangerzone environments.
 
     This class holds all the logic around checking and downloading PySide RPMs. It can
-    detect the PySide6 version that the project requires, check if an RPM is present
-    under "/dist", and download it.
+    check if the required RPM version is present under "/dist", and optionally download
+    it.
     """
 
     def __init__(self, distro_name, distro_version):
@@ -320,22 +321,9 @@ class PySide6Manager:
         self.distro_version = distro_version
 
     @property
-    @functools.lru_cache
     def version(self):
-        """Retrieve the PySide6 version from poetry.lock.
-
-        Read the poetry.lock file, and grep the version of the PySide6 library. The
-        results of this method call are cached, so we can call it repeatedly without any
-        performance cost.
-        """
-        # FIXME: I don't like regexes, but problem is that `tomllib` is not present in
-        # Python < 3.11. So, since we don't want to rely on an external library yet, we
-        # have to resort to regexes. Note that the regex we choose uses Shiboken6,
-        # mainly because the PySide6 package and its version are in different lines.
-        with open(git_root() / "poetry.lock") as f:
-            toml = f.read()
-            match = re.search(r'^shiboken6 = "([\d.]+)"$', toml, re.MULTILINE)
-            return match.groups()[0]
+        """The version of the PySide6 RPM."""
+        return PYSIDE6_VERSION
 
     @property
     def rpm_name(self):