diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index e6a839f..8bf4a26 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -15,7 +15,8 @@ jobs:
           - windows-latest
         ocaml-compiler:
           - "ocaml.5.0.0,ocaml-option-mingw"
-          - "ocaml.5.1.0,ocaml-option-mingw"
+          - "ocaml.5.1.1,ocaml-option-mingw"
+          - "ocaml.5.2.0,ocaml-option-mingw"
 
     runs-on: ${{ matrix.os }}
 
diff --git a/CHANGES.md b/CHANGES.md
index 873bd40..de15035 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,5 +1,6 @@
 ## Unreleased
 - Fix bug in Grpc-lwt-client to fetch status code from response header ([#58](https://github.com/dialohq/ocaml-grpc/pull/58)) ([acerone85](https://github.com/acerone85)) review by ([@quernd](https://github.com/quernd))
+- Update Async dependency to v0.17.0 ([#62](https://github.com/dialohq/ocaml-grpc/pull/62) ([@tmcgilchrist](https://github.com/tmcgilchrist))
 
 ## 0.2.0 2023-10-23
 
diff --git a/dune-project b/dune-project
index 32c4d3a..9225673 100644
--- a/dune-project
+++ b/dune-project
@@ -69,7 +69,7 @@
   (ocaml
    (>= 4.11))
   (async
-   (>= v0.16))
+   (>= v0.17))
   (grpc
    (= :version))
   (h2
@@ -100,7 +100,7 @@
   (network rpc serialisation))
  (depends
   (async
-   (>= v0.16.0))
+   (>= v0.17.0))
   cohttp
   cohttp-lwt
   cohttp-lwt-unix
diff --git a/grpc-async.opam b/grpc-async.opam
index fd4a3b4..8c3c8e7 100644
--- a/grpc-async.opam
+++ b/grpc-async.opam
@@ -21,7 +21,7 @@ bug-reports: "https://github.com/dialohq/ocaml-grpc/issues"
 depends: [
   "dune" {>= "3.7"}
   "ocaml" {>= "4.11"}
-  "async" {>= "v0.16"}
+  "async" {>= "v0.17"}
   "grpc" {= version}
   "h2" {>= "0.9.0"}
   "ppx_jane" {>= "v0.16.0"}
diff --git a/grpc-examples.opam b/grpc-examples.opam
index 0091766..dcd6f62 100644
--- a/grpc-examples.opam
+++ b/grpc-examples.opam
@@ -19,7 +19,7 @@ doc: "https://dialohq.github.io/ocaml-grpc"
 bug-reports: "https://github.com/dialohq/ocaml-grpc/issues"
 depends: [
   "dune" {>= "3.7"}
-  "async" {>= "v0.16.0"}
+  "async" {>= "v0.17.0"}
   "cohttp"
   "cohttp-lwt"
   "cohttp-lwt-unix"
diff --git a/lib/grpc-async/client.ml b/lib/grpc-async/client.ml
index 7331767..aa4ff42 100644
--- a/lib/grpc-async/client.ml
+++ b/lib/grpc-async/client.ml
@@ -21,12 +21,12 @@ let default_headers =
     [ ("te", "trailers"); ("content-type", "application/grpc+proto") ]
 
 let trailers_handler trailers_status_ivar headers =
-  Ivar.fill trailers_status_ivar (Grpc.Status.extract_status headers)
+  Async.Ivar.fill_exn trailers_status_ivar (Grpc.Status.extract_status headers)
 
 let response_handler read_body_ivar out_ivar (response : H2.Response.t)
     (body : H2.Body.Reader.t) =
-  Ivar.fill read_body_ivar body;
-  Ivar.fill out_ivar response
+  Async.Ivar.fill_exn read_body_ivar body;
+  Async.Ivar.fill_exn out_ivar response
 
 let call ~service ~rpc ?(scheme = "https") ~handler ~do_request
     ?(headers = default_headers) () =