diff --git a/.github/workflows/tox.yml b/.github/workflows/tox.yml
index f7d4cbb..520cd47 100644
--- a/.github/workflows/tox.yml
+++ b/.github/workflows/tox.yml
@@ -66,7 +66,6 @@ jobs:
       postgres:
         image: postgres
         env:
-          POSTGRES_PASSWORD: postgres
           POSTGRES_USER: postgres
           POSTGRES_PASSWORD: postgres
           POSTGRES_DB: django_anonymiser
@@ -89,7 +88,7 @@ jobs:
       - name: Install and run tox
         env:
           TOXENV: pg-only
-          DATABASE_URL: postgres://postgres:postgres@{env:POSTGRES_HOST:localhost}:{env.POSTGRES_PORT:5432}/{env.POSTGRES_DBNAME}
+          DATABASE_URL: postgres://${{env.POSTGRES_USER}}:${{env.POSTGRES_PASSWORD}}@${{env.POSTGRES_HOST}}:${{env.POSTGRES_PORT}}/${{env.POSTGRES_DBNAME}}
         run: |
           pip install tox
           tox