diff --git a/Makefile b/Makefile
index ab8cf2ee..a9485498 100644
--- a/Makefile
+++ b/Makefile
@@ -15,16 +15,23 @@ include extension-ci-tools/makefiles/duckdb_extension.Makefile
 # LoadInternal also calls ExtensionHelper::AutoLoadExtension(db, "icu") so
 # the timezone option is honoured. Autoload looks for the extension on disk
 # at $HOME/.duckdb/extensions/<duckdb_version>/<platform>/icu.duckdb_extension
-# and falls back to a hub download. Inside the linux_amd64 test docker
-# container that path is empty and there is no network egress, so the
-# autoload fails. We copy the icu.duckdb_extension that was built locally
-# as part of this extension's build (declared in extension_config.cmake)
-# into the expected path before running the unittester.
+# and falls back to a hub download. That fails both inside the linux_amd64
+# test docker container (empty path, no network egress) and on the macOS
+# osx_arm64 test runner (hub icu not reliably resolvable). We copy the
+# icu.duckdb_extension that was built locally as part of this extension's
+# build (declared in extension_config.cmake) into the expected path,
+# matched to the DuckDB platform string, before running the unittester.
 DUCKDB_VERSION_TAG := v1.4.4
 
 define stage_icu
 	@if [ -f ./build/$(1)/extension/icu/icu.duckdb_extension ]; then \
-	  platform=$$(uname -m | sed 's/x86_64/linux_amd64/;s/aarch64/linux_arm64/'); \
+	  case "$$(uname -s)-$$(uname -m)" in \
+	    Linux-x86_64)  platform=linux_amd64 ;; \
+	    Linux-aarch64) platform=linux_arm64 ;; \
+	    Darwin-arm64)  platform=osx_arm64 ;; \
+	    Darwin-x86_64) platform=osx_amd64 ;; \
+	    *)             platform=$$(uname -m) ;; \
+	  esac; \
 	  target=$$HOME/.duckdb/extensions/$(DUCKDB_VERSION_TAG)/$$platform; \
 	  mkdir -p "$$target" && cp -f ./build/$(1)/extension/icu/icu.duckdb_extension "$$target/" && \
 	  echo "Staged icu.duckdb_extension at $$target/"; \
diff --git a/src/include/tydef.hpp b/src/include/tydef.hpp
index b7b28109..b9860ca0 100644
--- a/src/include/tydef.hpp
+++ b/src/include/tydef.hpp
@@ -11,11 +11,27 @@ extern "C" {
     #include <meos_internal.h>
 }
 
-// Forward-compat alias for the meosType → MeosType rename (MobilityDB
-// pr785-sync-script).  Vcpkg's MEOS exposes `MeosType`; existing
-// MobilityDuck code still uses `meosType`.  This alias bridges the two
-// without touching every reference site.
-using meosType = MeosType;
+// MEOS naming history: `meosType` is the **pre-consolidation** spelling
+// and `MeosType` is the **post-consolidation** target (the rename is
+// part of the upstream consolidation sweep, not yet reached by the
+// vcpkg pin).  The current pin
+// (`vcpkg_ports/meos/portfile.cmake` REF f11b7443ee98…) is still
+// pre-consolidation and exposes `meosType` — see
+// meos/include/temporal/meos_catalog.h, where line 121 declares
+// `} meosType;`.  MobilityDuck's source consistently uses
+// `meosType` (verified via `grep -rn '\bmeosType\b' src/`), which
+// matches the pin, so no alias is needed today.
+//
+// An earlier version of this file added `using meosType = MeosType;`
+// as a forward-looking bridge for the eventual consolidation bump.
+// That alias references `MeosType`, which the current pin does NOT
+// yet expose, so it broke the build:
+//   "'MeosType' does not name a type; did you mean 'meosType'?".
+//
+// When the MEOS pin is bumped past the consolidation point, restore
+// a bridge here (`using meosType = MeosType;` becomes valid then) or
+// sweep the source `meosType → MeosType` in one PR — whichever the
+// project prefers at that time.
 
 namespace duckdb {
 
diff --git a/src/temporal/set.cpp b/src/temporal/set.cpp
index f1c26bd3..d63aee7c 100644
--- a/src/temporal/set.cpp
+++ b/src/temporal/set.cpp
@@ -945,6 +945,14 @@ static inline Set *date_to_set_duckdb(DateADT d) {
     return date_to_set(ToMeosDate(duckdb::date_t(d)));
 }
 
+// macOS LP64: int64 (long) and int64_t (long long) are the same width but
+// distinct types, so clang rejects passing bigint_to_set where a
+// Set *(*)(int64_t) is expected as a non-type template arg. The cast is a
+// no-op on Linux. See SetUnionScalarFunction<int64_t, ...> below.
+static inline Set *bigint_to_set_duckdb(int64_t i) {
+    return bigint_to_set(static_cast<int64>(i));
+}
+
 struct SetPtrState {
     Set *accumulated;
 };
@@ -1069,7 +1077,7 @@ void SetTypes::RegisterSetUnionAgg(ExtensionLoader &loader) {
             LogicalType::INTEGER, SetTypes::intset()));
     set_union_set.AddFunction(
         AggregateFunction::UnaryAggregateDestructor<SetPtrState, int64_t, string_t,
-            SetUnionScalarFunction<int64_t, bigint_to_set>>(
+            SetUnionScalarFunction<int64_t, bigint_to_set_duckdb>>(
             LogicalType::BIGINT, SetTypes::bigintset()));
     set_union_set.AddFunction(
         AggregateFunction::UnaryAggregateDestructor<SetPtrState, double, string_t,