diff --git a/.copier-answers.yml b/.copier-answers.yml
index 9246058..2fb7884 100644
--- a/.copier-answers.yml
+++ b/.copier-answers.yml
@@ -1,5 +1,5 @@
 # Changes here will be overwritten by Copier; NEVER EDIT MANUALLY
-_commit: v0.4.1-35-g49a4e75
+_commit: v0.4.2-2-g3f805ee
 _src_path: git+https://github.com/twsl/python-project-template
 author_email: 45483159+twsl@users.noreply.github.com
 author_username: twsl
diff --git a/.devcontainer/Dockerfile b/.devcontainer/Dockerfile
index 7efcb71..b677f4d 100755
--- a/.devcontainer/Dockerfile
+++ b/.devcontainer/Dockerfile
@@ -1,12 +1,9 @@
 # See here for image contents: https://github.com/devcontainers/images/blob/main/src/python/.devcontainer/Dockerfile
+# See here for proposed version of container: https://github.com/devcontainers/templates/blob/main/src/python/devcontainer-template.json
 
-# [Choice] Python version (use -bookworm or -bullseye variants on local arm64/Apple Silicon): 3, 3.12, 3.11, 3.10, 3.9, 3.8, 3-bookworm, 3.12-bookworm, 3.11-bookworm, 3.10-bookworm, 3.9-bookworm, 3.8-bookworm, 3-bullseye, 3.12-bullseye, 3.11-bullseye, 3.10-bullseye, 3.9-bullseye, 3.8-bullseye, 3-buster, 3.12-buster, 3.11-buster, 3.10-buster, 3.9-buster, 3.8-buster
-ARG VARIANT=3-bookworm
-FROM mcr.microsoft.com/devcontainers/python:1-${VARIANT}
-
-# Temporary: Upgrade python packages due to https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2022-40897
-# They are installed by the base image (python) which does not have the patch.
-RUN python3 -m pip install --upgrade setuptools
+# [Choice] Python version (use -bookworm or -bullseye variants on local arm64/Apple Silicon): 3, 3.13, 3.12, 3.11, 3.10, 3.9, 3-bookworm, 3.13-bookworm, 3.12-bookworm, 3.11-bookworm, 3.10-bookworm, 3.9-bookworm, 3-bullseye, 3.13-bullseye, 3.12-bullseye, 3.11-bullseye, 3.10-bullseye, 3.9-bullseye, 3-buster, 3.12-buster, 3.11-buster, 3.10-buster, 3.9-buster
+ARG VARIANT=3-trixie
+FROM mcr.microsoft.com/devcontainers/python:3-${VARIANT}
 
 RUN pip install --upgrade pip
 
diff --git a/.devcontainer/devcontainer.json b/.devcontainer/devcontainer.json
index aac91be..651d395 100755
--- a/.devcontainer/devcontainer.json
+++ b/.devcontainer/devcontainer.json
@@ -7,7 +7,7 @@
         "dockerfile": "Dockerfile",
         "context": "..",
         "args": {
-            "VARIANT": "3.11-bookworm"
+            "VARIANT": "3.11-trixie"
         }
     },
     "remoteEnv": {
diff --git a/pyproject.toml b/pyproject.toml
index fa3e9aa..27fb98e 100755
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -52,7 +52,7 @@ dev = [
     "copier>=9.14.1",
 ]
 test = [
-    "pytest>=9.0.2",
+    "pytest>=9.0.3",
     "pytest-cov>=7.1.0",
     "pytest-mock>=3.15.1",
     "pytest-cases>=3.10.1",
diff --git a/uv.lock b/uv.lock
index 9fa7133..874bd8c 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1878,7 +1878,7 @@ wheels = [
 
 [[package]]
 name = "pytest"
-version = "9.0.2"
+version = "9.0.3"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "colorama", marker = "sys_platform == 'win32'" },
@@ -1887,9 +1887,9 @@ dependencies = [
     { name = "pluggy" },
     { name = "pygments" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/d1/db/7ef3487e0fb0049ddb5ce41d3a49c235bf9ad299b6a25d5780a89f19230f/pytest-9.0.2.tar.gz", hash = "sha256:75186651a92bd89611d1d9fc20f0b4345fd827c41ccd5c299a868a05d70edf11", size = 1568901, upload-time = "2025-12-06T21:30:51.014Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/7d/0d/549bd94f1a0a402dc8cf64563a117c0f3765662e2e668477624baeec44d5/pytest-9.0.3.tar.gz", hash = "sha256:b86ada508af81d19edeb213c681b1d48246c1a91d304c6c81a427674c17eb91c", size = 1572165, upload-time = "2026-04-07T17:16:18.027Z" }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/3b/ab/b3226f0bd7cdcf710fbede2b3548584366da3b19b5021e74f5bde2a8fa3f/pytest-9.0.2-py3-none-any.whl", hash = "sha256:711ffd45bf766d5264d487b917733b453d917afd2b0ad65223959f59089f875b", size = 374801, upload-time = "2025-12-06T21:30:49.154Z" },
+    { url = "https://files.pythonhosted.org/packages/d4/24/a372aaf5c9b7208e7112038812994107bc65a84cd00e0354a88c2c77a617/pytest-9.0.3-py3-none-any.whl", hash = "sha256:2c5efc453d45394fdd706ade797c0a81091eccd1d6e4bccfcd476e2b8e0ab5d9", size = 375249, upload-time = "2026-04-07T17:16:16.13Z" },
 ]
 
 [[package]]
@@ -2045,7 +2045,7 @@ docs = [
     { name = "pymdown-extensions", specifier = ">=10.21" },
 ]
 test = [
-    { name = "pytest", specifier = ">=9.0.2" },
+    { name = "pytest", specifier = ">=9.0.3" },
     { name = "pytest-benchmark", extras = ["aspect", "histogram"], specifier = ">=5.2.3" },
     { name = "pytest-cases", specifier = ">=3.10.1" },
     { name = "pytest-cov", specifier = ">=7.1.0" },