diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d9c64287..e93547bf 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -43,8 +43,8 @@ jobs:
         os:
           - ubuntu-latest
         spack_version:
-          # In README.md we claim compatibility with v0.18.0
-          - v0.18.0
+          # In README.md we claim compatibility with v0.20.0
+          - v0.20.0
           - develop
         spack_spec:
           # `example` is a package in our custom Spack repo, ensure we can build
diff --git a/docs/install.md b/docs/install.md
index a4da1a66..42bf10cd 100644
--- a/docs/install.md
+++ b/docs/install.md
@@ -81,6 +81,11 @@ Check spack is in `$PATH`, for example
 spack --version
 ```
 
+### Version
+
+We recommend using the latest spack version (develop). Stable spack releases starting from v0.20.0 
+are supported. Older versions of spack may work but are not regularly tested.
+
 ### Notes
 
 _**Note**: if you have already installed spack locally and you want to upgrade to