diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 24ccfeff..72086f20 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -19,7 +19,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.11", "3.12", "3.13", "3.14"]
+        python-version: ["3.11", "3.12", "3.13", "3.14", "3.15"]
 
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
diff --git a/changelog.md b/changelog.md
index 33dab534..d129d754 100644
--- a/changelog.md
+++ b/changelog.md
@@ -18,6 +18,7 @@ Internal
 * Fix typo in class name `LimitedQuotePreservingConfigObj`.
 * Update `polars` to v2.0.0.
 * Update `altair` to v6.3.0.
+* Add Python 3.15 to CI.
 
 
 v2.28.2 (2026/10/07)
diff --git a/pyproject.toml b/pyproject.toml
index 5e4159df..9ba78a1f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -104,6 +104,7 @@ exclude-newer = '1 week'
 cli_helpers = false
 polars = false                              # temporary to get Polars 2.x, remove 1 week after 2026-10-06T11:44:04.327Z
 polars-runtime-32 = false                   # temporary to get Polars 2.x, remove 1 week after 2026-10-06T11:44:04.327Z
+pydantic_core = false                       # temporary to allow v2.50.0, remove 1 week after 2026-10-08
 
 [tool.ruff]
 target-version = 'py311'