Try develop

action.yml

@@ -47,14 +47,14 @@ runs:
       uses: actions/cache@v3
       with:
         path: ~/.mix
-        key: ${{ runner.arch }}-alpine-${{ inputs.alpine }}-pakman-8.1.6
+        key: ${{ runner.arch }}-alpine-${{ inputs.alpine }}-pakman-develop
 
     - name: Install Pakman
       if: steps.cache-pakman.outputs.cache-hit != 'true'
       run: |
         mix local.rebar --force
         mix local.hex --force
-        mix escript.install hex pakman 8.1.6 --force
+        mix escript.install github upmaru/pakman branch develop --force
       shell: alpine.sh {0}
       env:
         MIX_ENV: prod

mix.exs

@@ -60,7 +60,7 @@ defmodule Pakman.MixProject do
   def package do
     [
       description: "Build tool for opsmaru.com",
-      files: ["lib", "mix.exs", "README.md"],
+      files: ["lib", "config", "mix.exs", "README.md"],
       maintainers: ["Zack Siri"],
       licenses: ["MIT"],
       links: %{github: "https://github.com/upmaru/pakman"}