Emulated builds (e.g. via binfmt) also struggle with the problem.

Access to clocks and timings interferes with reproducibility, but they are very difficult system calls to take away.

In reply to @rosscomputerguy:matrix.org
Rip, openexr failed tests due to 1 test timing out

In reply to @rosscomputerguy:matrix.org
But I'm past that now

error: builder for '/nix/store/sq3vjc0dn0rsfhjvdgphgbyb2yipc77h-python3.12-hypothesis-6.112.2.drv' failed with exit code 1;
       last 25 log lines:
       > You can add @seed(166370714267267105264357939584607094565) to this test or run pytest with --hypothesis-seed=166370714267267105264357939584607094565 to reproduce thi.
       > ============================= slowest 20 durations =============================
       > 300.00s call     hypothesis-python/tests/cover/test_slices.py::test_start_will_equal_0
       > 215.85s call     hypothesis-python/tests/cover/test_stateful.py::TestLotsOfEntropyPerStepMachine::runTest
       > 138.40s call     hypothesis-python/tests/cover/test_stateful.py::test_removes_needless_steps
       > 125.83s call     hypothesis-python/tests/cover/test_stateful.py::test_saves_failing_example_in_database
       > 121.27s call     hypothesis-python/tests/cover/test_flakiness.py::test_failure_sequence_inducing
       > 110.93s call     hypothesis-python/tests/cover/test_database_backend.py::TestGADReads::runTest
       > 105.06s call     hypothesis-python/tests/cover/test_slices.py::test_step_will_be_negative
       > 91.98s call     hypothesis-python/tests/cover/test_statistical_events.py::test_stateful_with_one_of_bundles_states_are_deduped
       > 88.29s call     hypothesis-python/tests/cover/test_observability.py::test_observability
       > 81.35s call     hypothesis-python/tests/cover/test_stateful.py::TestMachineUsingMultiple::runTest
       > 67.26s call     hypothesis-python/tests/cover/test_statistical_events.py::test_stateful_states_are_deduped
       > 66.79s call     hypothesis-python/tests/cover/test_sampled_from.py::test_efficient_lists_of_tuples_first_element_sampled_from
       > 65.39s call     hypothesis-python/tests/cover/test_regex.py::test_fullmatch_generates_example[[ab]*-aBb]
       > 55.93s call     hypothesis-python/tests/cover/test_testdecorators.py::test_float_addition_is_associative
       > 54.70s call     hypothesis-python/tests/cover/test_type_lookup.py::test_can_generate_from_all_registered_types[BaseExceptionGroup]
       > 53.84s call     hypothesis-python/tests/cover/test_composite.py::test_can_shrink_matrices_with_length_param
       > 51.04s call     hypothesis-python/tests/cover/test_regex.py::test_matching[True-True-\\s-None]
       > 48.16s call     hypothesis-python/tests/cover/test_lookup.py::test_specialised_mapping_types[typing.OrderedDict[tests.cover.test_lookup.Elem, tests.cover.test_lookup]
       > 47.87s call     hypothesis-python/tests/cover/test_regex.py::test_matching[True-True-\\w-is_word]
       > 47.57s call     hypothesis-python/tests/cover/test_lookup.py::test_resolves_forwardrefs_to_builtin_types[object]
       > =========================== short test summary info ============================
       > FAILED tests/cover/test_stateful.py::test_can_run_with_no_db - hypothesis.errors.FailedHealthCheck: Data generation is extremely slow: Onl...
       > ====== 1 failed, 3211 passed, 5 skipped, 1 xfailed in 2774.21s (0:46:14) =======
       For full logs, run 'nix log /nix/store/sq3vjc0dn0rsfhjvdgphgbyb2yipc77h-python3.12-hypothesis-6.112.2.drv'.

Fun