diff --git a/.github/scripts/smoke_install.sh b/.github/scripts/smoke_install.sh
index f37e1df..ab7693d 100755
--- a/.github/scripts/smoke_install.sh
+++ b/.github/scripts/smoke_install.sh
@@ -13,4 +13,8 @@ else
   pip install ./PyAutoNerves ./PyAutoFit ./PyAutoArray ./PyAutoGalaxy ./PyAutoLens
   pip install numba
 fi
-pip install tensorflow-probability==0.25.0
+# NOTE: do NOT `pip install tensorflow-probability==0.25.0` here. The stable
+# release crashes at import under the resolved modern JAX
+# (`jax.interpreters.xla.pytype_aval_mappings` was removed), which broke the
+# JAX Matern-kernel (delaunay_mge) likelihood path. The working modified-Bessel
+# dependency is `tfp-nightly`, pinned by `PyAutoArray[optional]` above.