diff --git a/env/merlin/HiQsimulator/packages/py-projectq/package.py b/env/merlin/HiQsimulator/packages/py-projectq/package.py
index d71fb21..8a40abd 100644
--- a/env/merlin/HiQsimulator/packages/py-projectq/package.py
+++ b/env/merlin/HiQsimulator/packages/py-projectq/package.py
@@ -35,3 +35,4 @@ class PyProjectq(PythonPackage):
     depends_on("py-requests", type=("build", "run"))
     # conflict with pybind11@2.2.0 -> see requirements.txt
     depends_on("py-pybind11@1.7:2.1,2.2.1:", type=("build", "run"))
+    depends_on("py-networkx", type=("run"))