diff --git a/.reuse/dep5 b/.reuse/dep5
index 88b440270c..2818f1d821 100644
--- a/.reuse/dep5
+++ b/.reuse/dep5
@@ -10,6 +10,7 @@ Source: https://docs.sel4.systems
 # License: ...
 
 Files: Gemfile.lock
+       .ruby-version
        .bundle/config
        Hardware/HiKey/*.patch
        Hardware/CEI_TK1_SOM/CANBoard/Tegra_CANboard_tofab_v1.zip
diff --git a/.ruby-version b/.ruby-version
new file mode 100644
index 0000000000..6a81b4c837
--- /dev/null
+++ b/.ruby-version
@@ -0,0 +1 @@
+2.7.8