diff --git a/configs/common/packages.yaml b/configs/common/packages.yaml
index 1deb17e35..7f08bdf9b 100644
--- a/configs/common/packages.yaml
+++ b/configs/common/packages.yaml
@@ -75,8 +75,9 @@ packages:
     # Pin version to avoid duplicates
     require: '@2.6.4'
   fms:
-    require: '@2024.02'
-    variants: 'precision=32,64 +quad_precision +gfs_phys +openmp +pic constants=GFS build_type=Release +deprecated_io'
+    require:
+    - '@2024.02'
+    - 'precision=32,64 +quad_precision +gfs_phys +openmp +pic constants=GFS build_type=Release +deprecated_io'
   fontconfig:
     require: '+pic'
   freetype:
@@ -274,7 +275,8 @@ packages:
   w3nco:
     require: '@2.4.1'
   wgrib2:
-    require: '@3.1.1'
+    require:
+    - '@3.1.1'
   wrf-io:
     require: '@1.2.0'
   zstd:
diff --git a/configs/sites/tier2/macos.default/packages.yaml b/configs/sites/tier2/macos.default/packages.yaml
index f08498c65..ddb2d126f 100644
--- a/configs/sites/tier2/macos.default/packages.yaml
+++ b/configs/sites/tier2/macos.default/packages.yaml
@@ -1,9 +1,14 @@
 packages:
   cairo:
     variants: ~png ~svg
+  # https://github.com/JCSDA/spack-stack/issues/1211
+  fms:
+    require:
+    - '+shared'
   git:
     buildable: false
   libiconv:
     buildable: false
   wgrib2:
-    variants: ~openmp
+    require:
+    - '~openmp'
diff --git a/doc/source/NewSiteConfigs.rst b/doc/source/NewSiteConfigs.rst
index b4116538c..afd5305b0 100644
--- a/doc/source/NewSiteConfigs.rst
+++ b/doc/source/NewSiteConfigs.rst
@@ -152,6 +152,9 @@ These instructions are meant to be a reference that users can follow to set up t
    brew install libiconv
    # Note - need to pin to version 5
    brew install qt@5
+   # Note - For Sonoma only, install m4 and pkg-config
+   brew install m4
+   brew install pkg-config
 
    # Note - only needed for running JCSDA's
    # JEDI-Skylab system (using R2D2 localhost)
@@ -248,6 +251,9 @@ Remember to activate the ``lua`` module environment and have MacTeX in your sear
    PATH="$HOMEBREW_ROOT/opt/qt@5/bin:$PATH" \
         spack external find --scope system qt
 
+   PATH="$HOMEBREW_ROOT/opt/m4/bin:$PATH" \
+        spack external find --scope system m4
+
    # Optional, only if planning to build jedi-tools environment with LaTeX support
    # The texlive bin directory must have been added to PATH (see above)
    spack external find --scope system texlive
diff --git a/spack b/spack
index 78e0c1d5b..1b3e3e525 160000
--- a/spack
+++ b/spack
@@ -1 +1 @@
-Subproject commit 78e0c1d5b83ff2874ec803ce25d08b014b5c8cc3
+Subproject commit 1b3e3e5252e5b0e4cb28f9e4255e84ea1a06ff5f