diff --git a/.github/workflows/build-and-deploy.yml b/.github/workflows/build-and-deploy.yml
index 7c5ca664..297c8405 100644
--- a/.github/workflows/build-and-deploy.yml
+++ b/.github/workflows/build-and-deploy.yml
@@ -67,4 +67,4 @@ jobs:
         env:
           KUBE_CONFIG_FILE: ${{ secrets.KUBE_CONFIG_FILE }}
         with:
-          namespace: workadventure-${{GITHUB_REF_SLUG}}
+          namespace: workadventure-${{ env.GITHUB_REF_SLUG }}
diff --git a/deeployer.libsonnet b/deeployer.libsonnet
index 599012c4..4e44db34 100644
--- a/deeployer.libsonnet
+++ b/deeployer.libsonnet
@@ -1,6 +1,5 @@
 {
   local env = std.extVar("env"),
-  # FIXME: namespace does not work if the branch contains a "/"
   local namespace = env.GITHUB_REF_SLUG,
   local tag = if namespace == "master" then "latest" else namespace,
   "$schema": "https://raw.githubusercontent.com/thecodingmachine/deeployer/master/deeployer.schema.json",