diff --git a/modules/programs/zsh/history.nix b/modules/programs/zsh/history.nix
index acdc6531f..fcd880c46 100644
--- a/modules/programs/zsh/history.nix
+++ b/modules/programs/zsh/history.nix
@@ -247,28 +247,12 @@ in
           # https://github.com/zsh-users/zsh-history-substring-search#usage
           ''
             source ${pkgs.zsh-history-substring-search}/share/zsh-history-substring-search/zsh-history-substring-search.zsh
-
-            ${
-              let
-                upKeys = lib.toList cfg.historySubstringSearch.searchUpKey;
-                downKeys = lib.toList cfg.historySubstringSearch.searchDownKey;
-              in
-              ''
-                # Bind search up keys
-                ${lib.hm.zsh.define "search_up_keys" upKeys}
-                 for key in "''${search_up_keys[@]}"; do
-                   bindkey "$key" history-substring-search-up
-                 done
-                 unset key search_up_keys
-
-                # Bind search down keys
-                ${lib.hm.zsh.define "search_down_keys" downKeys}
-                 for key in "''${search_down_keys[@]}"; do
-                   bindkey "$key" history-substring-search-down
-                 done
-                 unset key search_down_keys
-              ''
-            }
+            ${lib.concatMapStringsSep "\n" (upKey: ''bindkey "${upKey}" history-substring-search-up'') (
+              lib.toList cfg.historySubstringSearch.searchUpKey
+            )}
+            ${lib.concatMapStringsSep "\n" (downKey: ''bindkey "${downKey}" history-substring-search-down'') (
+              lib.toList cfg.historySubstringSearch.searchDownKey
+            )}
           ''
       ))
     ];
diff --git a/tests/modules/programs/zsh/history-substring-search-expected.zshrc b/tests/modules/programs/zsh/history-substring-search-expected.zshrc
index a73c04322..e95c88c47 100644
--- a/tests/modules/programs/zsh/history-substring-search-expected.zshrc
+++ b/tests/modules/programs/zsh/history-substring-search-expected.zshrc
@@ -36,22 +36,6 @@ done
 unset opt disabled_opts
 
 source @zsh-history-substring-search@/share/zsh-history-substring-search/zsh-history-substring-search.zsh
-
-# Bind search up keys
-search_up_keys=(
-  '^[[A' '\eOA'
-)
- for key in "${search_up_keys[@]}"; do
-   bindkey "$key" history-substring-search-up
- done
- unset key search_up_keys
-
-# Bind search down keys
-search_down_keys=(
-  '^[[B'
-)
- for key in "${search_down_keys[@]}"; do
-   bindkey "$key" history-substring-search-down
- done
- unset key search_down_keys
-
+bindkey "^[[A" history-substring-search-up
+bindkey "\eOA" history-substring-search-up
+bindkey "^[[B" history-substring-search-down