diff --git a/CHANGES.md b/CHANGES.md
index 2150432..f188ec1 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,8 @@
+# 0.5.1 (2021-07-01)
+
+- Fix for transitive dependency in cuz
+- Improved lower bounds on the opam file
+
 # 0.5.0 (2021-07-01)
 
 - Use cuz for the get calls with compression
diff --git a/doi2bib.opam b/doi2bib.opam
index f473984..b4760f5 100644
--- a/doi2bib.opam
+++ b/doi2bib.opam
@@ -15,6 +15,8 @@ depends: [
   "cmdliner" {>= "1.0.0"}
   "decompress" {>= "1.3.0"}
   "ezxmlm" {>= "1.1.0"}
+  "lwt" {>= "5.2.0"}
+  "bigstringaf" {>= "0.2.0"}
   "tls" {>= "0.12.0"}
   "re" {>= "1.0.0"}
   "odoc" {with-doc}
diff --git a/dune-project b/dune-project
index e456a36..b6fb766 100644
--- a/dune-project
+++ b/dune-project
@@ -32,6 +32,10 @@
    (>= 1.3.0))
   (ezxmlm
    (>= 1.1.0))
+  (lwt
+   (>= 5.2.0))
+  (bigstringaf
+   (>= 0.2.0))
   (tls
    (>= 0.12.0))
   (re
diff --git a/lib/dune b/lib/dune
index f88e69a..a65e92b 100644
--- a/lib/dune
+++ b/lib/dune
@@ -1,4 +1,4 @@
 (library
  (name doi2bib)
- (libraries astring cohttp-lwt-unix cuz.cohttp ezxmlm re unix)
+ (libraries astring cohttp-lwt-unix cuz.cohttp ezxmlm lwt re unix)
  (preprocess future_syntax))
diff --git a/vendor/cuz/dune-project b/vendor/cuz/dune-project
index 75f0c34..82b4049 100644
--- a/vendor/cuz/dune-project
+++ b/vendor/cuz/dune-project
@@ -20,6 +20,8 @@
  (depends
   (ocaml
    (>= 4.08))
+  (bigstringaf
+   (>= 0.5.0))
   (cohttp-lwt
    (>= 2.5.0))
   (decompress
diff --git a/vendor/cuz/src/dune b/vendor/cuz/src/dune
index 9951e4e..d6a35fd 100644
--- a/vendor/cuz/src/dune
+++ b/vendor/cuz/src/dune
@@ -2,7 +2,7 @@
  (public_name cuz)
  (name cuz)
  (modules :standard \ cuz_unix cuz_cohttp)
- (libraries cohttp-lwt decompress.gz decompress.de)
+ (libraries bigstringaf cohttp-lwt decompress.gz decompress.de)
  (preprocess future_syntax))
 
 (library