diff --git a/action.yml b/action.yml
index d7f5d24..3db623f 100644
--- a/action.yml
+++ b/action.yml
@@ -12,7 +12,7 @@ runs:
     - shell: bash
       run: |
         set -euxo pipefail
-        tempdir = $(mktemp -d)
+        tempdir=$(mktemp -d)
         pushd $tempdir
         curl -o nim.tar.xz https://nim-lang.org/download/nim-${{ inputs.version }}-linux_x64.tar.xz
         tar -xf nim.tar.xz