diff --git a/var/spack/repos/builtin/packages/py-macs3/package.py b/var/spack/repos/builtin/packages/py-macs3/package.py
index be94b9c290c..1a218e44a6e 100644
--- a/var/spack/repos/builtin/packages/py-macs3/package.py
+++ b/var/spack/repos/builtin/packages/py-macs3/package.py
@@ -24,3 +24,5 @@ class PyMacs3(PythonPackage):
     depends_on("py-numpy@1.19:", type=("build", "run"))
     depends_on("py-cykhash@2", type=("build", "run"))
     depends_on("py-hmmlearn@0.3:", type=("build", "run"))
+
+    depends_on("zlib-api")