diff --git a/README.md b/README.md
index e486180..909b88d 100644
--- a/README.md
+++ b/README.md
@@ -33,3 +33,13 @@ jobs:
       - uses: julia-actions/julia-buildpkg@v1
       - uses: julia-actions/julia-runtest@v1
 ```
+
+
+### Registry flavor preference
+
+This actions defines (and exports for subsequent steps of the workflow) the
+environmental variable `JULIA_PKG_SERVER_REGISTRY_PREFERENCE=eager` unless it
+is already set. If you want another registry flavor (i.e. `conservative`) this
+should be defined in the `env:` section of the relevant workflow or step. See
+[Registry flavors](https://pkgdocs.julialang.org/dev/registries/#Registry-flavors)
+for more information.
diff --git a/action.yml b/action.yml
index 0f2e7f2..9ca9427 100644
--- a/action.yml
+++ b/action.yml
@@ -17,11 +17,13 @@ inputs:
 runs:
   using: 'composite'
   steps:
+  - name: Set and export registry flavor preference
+    run: echo "JULIA_PKG_SERVER_REGISTRY_PREFERENCE=${JULIA_PKG_SERVER_REGISTRY_PREFERENCE:-eager}" >> ${GITHUB_ENV}
+    shell: bash
   - run: |
       import Pkg
       VERSION >= v"1.5-" && Pkg.Registry.add("General")
       VERSION >= v"1.1.0-rc1" ? Pkg.build(verbose=true) : Pkg.build()
     shell: julia --color=yes --project=${{ inputs.project }} {0}
     env:
-      JULIA_PKG_SERVER_REGISTRY_PREFERENCE: "${{ env.JULIA_PKG_SERVER_REGISTRY_PREFERENCE == '' && 'eager' || env.JULIA_PKG_SERVER_REGISTRY_PREFERENCE }}"
       JULIA_PKG_PRECOMPILE_AUTO: "${{ inputs.precompile }}"