diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 9b020f0cb7..621c291319 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -40,6 +40,7 @@ jobs:
       - name: Install Poetry
         uses: snok/install-poetry@v1
         with:
+          version: 1.8.5
           virtualenvs-create: true
           virtualenvs-in-project: true
           virtualenvs-path: .venv
@@ -165,6 +166,7 @@ jobs:
       - name: Install Poetry
         uses: snok/install-poetry@v1
         with:
+          version: 1.8.5
           virtualenvs-create: true
           virtualenvs-in-project: true
           virtualenvs-path: .venv
diff --git a/docs/developing-locust.rst b/docs/developing-locust.rst
index dcd553cb5c..59c26faca4 100644
--- a/docs/developing-locust.rst
+++ b/docs/developing-locust.rst
@@ -16,7 +16,7 @@ Fork Locust on `GitHub <https://github.com/locustio/locust/>`_ and then
     # clone the repo:
     $ git clone git://github.com/<YourName>/locust.git
 
-    # install the poetry build system, see https://python-poetry.org/docs/#installation
+    # install the poetry build system, version 1.8.5, see https://python-poetry.org/docs/#installation
 
     # install the required poetry plugins:
     $ poetry self add "poethepoet[poetry_plugin]"