diff --git a/.github/workflows/benchmark-linux.yml b/.github/workflows/benchmark-linux.yml
index 56ba9d5..a8ed5f4 100644
--- a/.github/workflows/benchmark-linux.yml
+++ b/.github/workflows/benchmark-linux.yml
@@ -55,15 +55,23 @@ jobs:
       - name: Synchronize frozen Python environment
         run: nix develop --command uv sync --frozen
 
+      - name: Install isolated TsFile claim dependencies
+        if: inputs.profile == 'claims'
+        run: |
+          nix develop --command uv pip install --python .venv/bin/python \
+            pytz==2026.2 tzdata==2026.3
+          nix develop --command uv pip install --python .venv/bin/python --no-deps \
+            pandas==2.2.3 tsfile==2.3.1
+
       - name: Run selected benchmark lane
         id: benchmark
         run: |
-          result=$(nix develop --command uv run --frozen format-bench run \
+          result=$(nix develop --command .venv/bin/format-bench run \
             --profile "${{ inputs.profile }}" \
             --dataset github-stars-2026-07-03)
           run_dir=$(dirname "$result")
-          nix develop --command uv run --frozen format-bench report --run-dir "$run_dir"
-          archive=$(nix develop --command uv run --frozen format-bench package \
+          nix develop --command .venv/bin/format-bench report --run-dir "$run_dir"
+          archive=$(nix develop --command .venv/bin/format-bench package \
             --run-dir "$run_dir" \
             --platform linux-x86_64)
           echo "archive=$archive" >> "$GITHUB_OUTPUT"
diff --git a/src/format_bench/runner.py b/src/format_bench/runner.py
index b5c8299..d50c449 100644
--- a/src/format_bench/runner.py
+++ b/src/format_bench/runner.py
@@ -145,7 +145,17 @@ def _sha256(path: Path) -> str:
 
 def environment_info(root: Path) -> dict:
     packages = {}
-    for name in ("pyarrow", "pylance", "tiktoken", "vortex-data", "zstandard"):
+    for name in (
+        "pandas",
+        "pyarrow",
+        "pylance",
+        "pytz",
+        "tiktoken",
+        "tsfile",
+        "tzdata",
+        "vortex-data",
+        "zstandard",
+    ):
         try:
             packages[name] = version(name)
         except PackageNotFoundError:
diff --git a/tests/test_runner.py b/tests/test_runner.py
index aa1f12a..40653d2 100644
--- a/tests/test_runner.py
+++ b/tests/test_runner.py
@@ -7,6 +7,7 @@
 from format_bench.runner import (
     Job,
     MeasurementConfig,
+    environment_info,
     measure_callable,
     run_job,
     stats_ms,
@@ -47,3 +48,8 @@ def test_run_job_aggregates_fresh_process_output(tmp_path: Path) -> None:
     assert result["fresh_process"]["samples"] == 2
     assert result["warm"]["samples"] == 4
     assert result["max_rss_bytes_p50"] == 100
+
+
+def test_environment_records_isolated_claim_dependencies() -> None:
+    packages = environment_info(Path(__file__).parents[1])["packages"]
+    assert {"pandas", "pytz", "tsfile", "tzdata"} <= packages.keys()