diff --git a/krebs/5pkgs/simple/git-preview/default.nix b/krebs/5pkgs/simple/git-preview/default.nix
index 77826f34b..da1525072 100644
--- a/krebs/5pkgs/simple/git-preview/default.nix
+++ b/krebs/5pkgs/simple/git-preview/default.nix
@@ -9,7 +9,11 @@ writeDashBin "git-preview" ''
   preview_name=$(${coreutils}/bin/basename "$preview_dir")
   ${git}/bin/git worktree add --detach -f "$preview_dir" 2>/dev/null
   ${git}/bin/git -C "$preview_dir" checkout -q "$head_commit"
-  ${git}/bin/git -C "$preview_dir" merge -qm "$merge_message" "$merge_commit"
+  ${git}/bin/git -C "$preview_dir" merge \
+      ''${GIT_PREVIEW_MERGE_STRATEGY+-s "$GIT_PREVIEW_MERGE_STRATEGY"} \
+      -m "$merge_message" \
+      -q \
+      "$merge_commit"
   ${git}/bin/git -C "$preview_dir" diff "$head_commit.." "$@"
   ${coreutils}/bin/rm -fR "$preview_dir"
   ${coreutils}/bin/rm -R .git/worktrees/"$preview_name"