diff --git a/conda/build.sh b/conda/build.sh
index 27ee015269..83a32439f6 100644
--- a/conda/build.sh
+++ b/conda/build.sh
@@ -7,6 +7,9 @@ fi
 
 if [ `uname` == Darwin ]; then
     PY_LIB="libpython${MY_PY_VER}.dylib"
+    export   CFLAGS="$CFLAGS   -Wl,-flat_namespace,-undefined,suppress"
+    export CXXFLAGS="$CXXFLAGS -Wl,-flat_namespace,-undefined,suppress"
+    export  LDFLAGS="$LDFLAGS  -Wl,-flat_namespace,-undefined,suppress"
 else
     PY_LIB="libpython${MY_PY_VER}.so"
 fi
diff --git a/conda/meta.yaml b/conda/meta.yaml
index c81fdcec4c..88248f7f4e 100644
--- a/conda/meta.yaml
+++ b/conda/meta.yaml
@@ -25,6 +25,7 @@ requirements:
     - libboost
     - icu
   run:
+    - libgcc  # [osx]
     - python
     - oce ==0.17.3
     - libboost