diff --git a/.gitmodules b/.gitmodules
index 6a111cdb..1554e2c4 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,6 @@
 [submodule "vendor/opentelemetry-proto"]
 	path = vendor/opentelemetry-proto
 	url = https://github.com/open-telemetry/opentelemetry-proto
+[submodule "vendor/atomic"]
+	path = vendor/atomic
+	url = https://github.com/c-cube/ocaml-atomic.git
diff --git a/dune-project b/dune-project
index d5a78af6..03b38470 100644
--- a/dune-project
+++ b/dune-project
@@ -38,6 +38,8 @@
   (depends
    (ocaml (>= "4.08"))
    (dune (>= "2.3"))
+   mtime
+   atomic
    (opentelemetry (= :version))
    (ocaml-protoc (>= 2.1))
    (odoc :with-doc)
diff --git a/opentelemetry-client-ocurl.opam b/opentelemetry-client-ocurl.opam
index 7c4924a1..52aca892 100644
--- a/opentelemetry-client-ocurl.opam
+++ b/opentelemetry-client-ocurl.opam
@@ -10,6 +10,8 @@ bug-reports:
 depends: [
   "ocaml" {>= "4.08"}
   "dune" {>= "2.3"}
+  "mtime"
+  "atomic"
   "opentelemetry" {= version}
   "ocaml-protoc" {>= "2.1"}
   "odoc" {with-doc}
diff --git a/vendor/atomic b/vendor/atomic
new file mode 160000
index 00000000..7802992a
--- /dev/null
+++ b/vendor/atomic
@@ -0,0 +1 @@
+Subproject commit 7802992a568bf86c940e1c08a208e85102a0df6b
diff --git a/vendor/dune b/vendor/dune
new file mode 100644
index 00000000..b4ba0b2b
--- /dev/null
+++ b/vendor/dune
@@ -0,0 +1 @@
+(vendored_dirs atomic)