diff --git a/pyproject.toml b/pyproject.toml
index 7ed7dc2..e3bec71 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -49,7 +49,7 @@ Tracker = "https://github.com/QCoDeS/Qcodes_loop/issues"
 
 [project.optional-dependencies]
 qtplot = ["pyqtgraph>=0.11.0"]
-slack = ["slack-sdk>=3.4.2"]
+slack = ["slack-sdk>=3.4.2", "requests"]
 test = [
     "coverage[toml]>=6.0.0",
     "hypothesis>=5.49.0",
@@ -59,6 +59,7 @@ test = [
     "pyqtgraph>=0.11.0", # pyqtgraph tests
     "PyQt5>=5.15.0", # pyqtgraph tests
     "slack-sdk>=3.4.2", # needed to typecheck slack extension
+    "requests", # types in slack tests
 ]
 docs = [
     "nbsphinx>=0.8.9",