diff --git a/.github/workflows/build_macos.yml b/.github/workflows/build_macos.yml
index e4e03dac..703d6562 100644
--- a/.github/workflows/build_macos.yml
+++ b/.github/workflows/build_macos.yml
@@ -46,7 +46,7 @@ jobs:
           CIBW_BUILD: "cp*-${{ matrix.cibw-arch }}"
           CIBW_ARCHS_MACOS: x86_64 arm64 universal2
           CIBW_BEFORE_ALL: pip install --upgrade pip
-          CIBW_BEFORE_BUILD_MACOS: conda activate && brew install eigen
+          CIBW_BEFORE_BUILD_MACOS: conda init zsh && conda activate && brew install eigen
           CIBW_BUILD_VERBOSITY: 3
           CIBW_SKIP: "cp310-*"
           CIBW_ENVIRONMENT: CMAKE_BUILD_PARALLEL_LEVEL=2