diff --git a/src/global/import.ml b/src/global/import.ml
index ffc78d11b3..55fd1a21f5 100644
--- a/src/global/import.ml
+++ b/src/global/import.ml
@@ -11,6 +11,9 @@ module String = struct
       false
     with Exit -> true
 
+  let is_sub_ignore_case pattern text =
+    contains_s (lowercase_ascii text) (lowercase_ascii pattern)
+
   (* ripped off stringext, itself ripping it off from one of dbuenzli's libs *)
   let cut s ~on =
     let sep_max = length on - 1 in
diff --git a/src/ocamlorg_web/lib/handler.ml b/src/ocamlorg_web/lib/handler.ml
index 10e15b8ecc..44e81d2171 100644
--- a/src/ocamlorg_web/lib/handler.ml
+++ b/src/ocamlorg_web/lib/handler.ml
@@ -172,9 +172,7 @@ let academic_users req =
     let open Data.Academic_institution in
     let pattern = String.lowercase_ascii pattern in
     let name_is_s { name; _ } = String.lowercase_ascii name = pattern in
-    let name_contains_s { name; _ } =
-      String.contains_s (String.lowercase_ascii name) pattern
-    in
+    let name_contains_s { name; _ } = String.is_sub_ignore_case pattern name in
     let score user =
       if name_is_s user then -1
       else if name_contains_s user then 0
@@ -233,18 +231,17 @@ let books req =
 let releases req =
   let search_release pattern t =
     let open Data.Release in
-    let pattern = String.lowercase_ascii pattern in
-    let version_is_s { version; _ } =
-      String.lowercase_ascii version = pattern
+    let is_version { version; _ } =
+      String.(lowercase_ascii version = lowercase_ascii pattern)
     in
     let version_contains_s { version; _ } =
-      String.contains_s (String.lowercase_ascii version) pattern
+      String.is_sub_ignore_case pattern version
     in
     let body_contains_s { body_md; _ } =
-      String.contains_s (String.lowercase_ascii body_md) pattern
+      String.is_sub_ignore_case pattern body_md
     in
     let score release =
-      if version_is_s release then -1
+      if is_version release then -1
       else if version_contains_s release then 0
       else if body_contains_s release then 2
       else failwith "impossible release score"
@@ -400,18 +397,17 @@ let governance_team req =
 let papers req =
   let search_paper pattern t =
     let open Data.Paper in
-    let pattern = String.lowercase_ascii pattern in
-    let title_is_s { title; _ } = String.lowercase_ascii title = pattern in
+    let title_is_s { title; _ } =
+      String.(lowercase_ascii title = lowercase_ascii pattern)
+    in
     let title_contains_s { title; _ } =
-      String.contains_s (String.lowercase_ascii title) pattern
+      String.is_sub_ignore_case pattern title
     in
     let abstract_contains_s { abstract; _ } =
-      String.contains_s (String.lowercase_ascii abstract) pattern
+      String.is_sub_ignore_case pattern abstract
     in
     let has_tag_s { tags; _ } =
-      List.exists
-        (fun tag -> String.contains_s (String.lowercase_ascii tag) pattern)
-        tags
+      List.exists (fun tag -> String.is_sub_ignore_case pattern tag) tags
     in
     let score paper =
       if title_is_s paper then -1