diff --git a/test/test.ml b/test/test.ml
index 0377c075..d26cb7ee 100644
--- a/test/test.ml
+++ b/test/test.ml
@@ -741,6 +741,22 @@ let test_late_bootstrap ~net =
      so we wait too, to ensure it's done. *)
   Fiber.yield ()
 
+let test_listen_address () =
+  let location = Alcotest.of_pp Capnp_rpc_unix.Network.Location.pp in
+  let result = Alcotest.result location Alcotest.string in
+  let test expected s =
+    let x = Capnp_rpc_unix.Network.Location.of_string s |> Result.map_error (fun (`Msg m) -> m) in
+    Alcotest.check result s expected x
+  in
+  test (Ok (`TCP ("127.0.0.1", 7000))) "tcp:127.0.0.1:7000";
+  test (Ok (`TCP ("::1", 7000))) "tcp:[::1]:7000";
+  test (Ok (`TCP ("example.org", 7000))) "tcp:example.org:7000";
+  test (Ok (`Unix "/run/socket")) "unix:/run/socket";
+  test (Error {|Missing port in IPv6 address "[::1]"|}) "tcp:[::1]";
+  test (Error {|Invalid port ":1:7000" in listen address "::1:7000"|}) "tcp:::1:7000";
+  test (Error {|Missing :PORT in listen address "127.0.0.1"|}) "tcp:127.0.0.1";
+  test (Error {|Only tcp:HOST:PORT and unix:PATH addresses are currently supported|}) "http://localhost"
+
 let run name fn = Alcotest.test_case name `Quick fn
 
 let rpc_tests ~net ~dir =
@@ -775,6 +791,7 @@ let rpc_tests ~net ~dir =
     run_eio "File store"          (test_file_store ~dir);
     run_eio "Await settled"       test_await_settled;
     run_eio "Late bootstrap"      test_late_bootstrap;
+    run     "Listen address"      test_listen_address;
   ]
 
 let () =
diff --git a/unix/network.ml b/unix/network.ml
index 777c6ce1..b148998f 100644
--- a/unix/network.ml
+++ b/unix/network.ml
@@ -4,8 +4,6 @@ module Log = Capnp_rpc.Debug.Log
 module Tls_wrapper = Capnp_rpc_net.Tls_wrapper
 
 module Location = struct
-  open Astring
-
   include Capnp_rpc_net.Capnp_address.Location
 
   let abs_path p =
@@ -21,16 +19,25 @@ module Location = struct
   let tcp ~host ~port = `TCP (host, port)
 
   let parse_tcp s =
-    match String.cut ~sep:":" s with
-    | None -> Error (`Msg "Missing :PORT in listen address")
-    | Some (host, port) ->
-      match String.to_int port with
-      | None -> Error (`Msg "PORT must be an integer")
-      | Some port ->
+    if String.starts_with ~prefix:"[" s then (
+      match Ipaddr.with_port_of_string ~default:(-1) s with
+      | Ok (_, -1) -> Fmt.error_msg "Missing port in IPv6 address %S" s
+      | Ok (host, port) ->
+        let host = Ipaddr.to_string host in
         Ok (tcp ~host ~port)
+      | Error (`Msg m) -> Fmt.error_msg "Invalid IPv6 address %S: %s" s m
+    ) else (
+      match Astring.String.cut ~sep:":" s with
+      | None -> Fmt.error_msg "Missing :PORT in listen address %S" s
+      | Some (host, port) ->
+        match int_of_string_opt port with
+        | None -> Fmt.error_msg "Invalid port %S in listen address %S" port s
+        | Some port ->
+          Ok (tcp ~host ~port)
+    )
 
   let of_string s =
-    match String.cut ~sep:":" s with
+    match Astring.String.cut ~sep:":" s with
     | Some ("unix", path) -> Ok (unix path)
     | Some ("tcp", tcp) -> parse_tcp tcp
     | None -> Error (`Msg "Missing ':'")