diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 255ce63308..a5e7da47c8 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -255,6 +255,7 @@ jobs:
           cd ../bsdd && make test || ERROR=1
           pip install deepdiff
           cd ../ifcdiff && make test || ERROR=1
+          pip install toposort igraph
           cd ../ifcpatch && make test || ERROR=1
           pip install -e ../ifc5d --no-deps
           pip install odfpy xlsxwriter