diff --git a/builder-web.opam b/builder-web.opam
index 18ceb87..4341386 100644
--- a/builder-web.opam
+++ b/builder-web.opam
@@ -46,8 +46,8 @@ depends: [
   "cmarkit" {>= "0.3.0"}
   "tar" {>= "3.0.0"}
   "tar-unix" {>= "3.0.0"}
-  "owee"
-  "solo5-elftool" {>= "0.3.0" & < "0.4.0"}
+  "cachet"
+  "solo5-elftool" {>= "0.4.0"}
   "decompress" {>= "1.5.0"}
   "digestif" {>= "1.2.0"}
   "uuidm" {>= "0.9.9"}
diff --git a/lib/model.ml b/lib/model.ml
index 3b3aa66..9380054 100644
--- a/lib/model.ml
+++ b/lib/model.ml
@@ -59,17 +59,22 @@ let build_artifacts build (module Db : CONN) =
   List.map snd
 
 let solo5_manifest datadir file =
-  (* inlined from Owee_buf.map_binary *)
-  let path = Fpath.(to_string (datadir // artifact_path file)) in
-  let fd = Unix.openfile path [Unix.O_RDONLY] 0 in
-  let len = Unix.lseek fd 0 Unix.SEEK_END in
-  let buf =
-    Bigarray.array1_of_genarray
-      (Unix.map_file fd Bigarray.int8_unsigned
-         Bigarray.c_layout false [|len|]) in
-  Unix.close fd;
-  (* end of inlined code *)
-  Solo5_elftool.query_manifest buf |> Result.to_option
+  let cachet =
+    let path = Fpath.(to_string (datadir // artifact_path file)) in
+    let fd = Unix.openfile path [Unix.O_RDONLY] 0 in
+    let len = Unix.lseek fd 0 Unix.SEEK_END in
+    let buf =
+      Bigarray.array1_of_genarray
+        (Unix.map_file fd Bigarray.char
+           Bigarray.c_layout false [|len|]) in
+    Unix.close fd;
+    let map () ~pos len =
+      let len = min len (max 0 (Bigarray.Array1.dim buf - pos)) in
+      Bigarray.Array1.sub buf pos len
+    in
+    Cachet.make ~pagesize:8 ~map ()
+  in
+  Solo5_elftool.query_manifest cachet |> Result.to_option
 
 let platforms_of_job id (module Db : CONN) =
   Db.collect_list Builder_db.Build.get_platforms_for_job id