diff --git a/CHANGES.md b/CHANGES.md
index 040d0f55..bd0af461 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -22,8 +22,6 @@ It is recommended to upgrade in stages, checking your application still works af
    Calls to functions in the `Capnp_rpc_unix` and `Capnp_rpc_net` modules will need minor updates.
    They were previously called from Lwt context, so you'll need to wrap them with `Lwt_eio.run_eio`
    (or remove a `Lwt_eio.run_lwt` if you already updated the surrounding code).
-   You should also use `mirage-crypto-rng-eio` to ensure randomness is available
-   (`capnp-rpc-unix` no longer does this, although some other library might).
 
 4. Upgrade code and libraries using `Capnp_rpc_lwt`:
 
diff --git a/README.md b/README.md
index 4946bdaa..04754b47 100644
--- a/README.md
+++ b/README.md
@@ -462,7 +462,6 @@ let start_server ~sw ~delay net =
 
 let () =
   Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Switch.run @@ fun sw ->
   let delay = Eio.Time.Timeout.seconds env#mono_clock delay in
   let uri = start_server ~sw ~delay env#net in
@@ -476,12 +475,11 @@ let () =
   <img src="./diagrams/vats.svg"/>
 </p>
 
-You'll need to edit your `dune` file to add dependencies
-on `capnp-rpc-unix` and `mirage-crypto-rng-eio` in the `(libraries ...` line and also:
+You'll need to edit your `dune` file to add a dependency on `capnp-rpc-unix` in the `(libraries ...)` line and also:
 
 <!-- $MDX skip -->
 ```sh
-$ opam install capnp-rpc-unix mirage-crypto-rng-eio
+$ opam install capnp-rpc-unix
 ```
 
 Running this will give something like:
@@ -569,7 +567,7 @@ Edit the `dune` file to build a client and server:
 ```
 (executables
  (names client server)
- (libraries eio_main capnp-rpc logs.fmt capnp-rpc-unix mirage-crypto-rng-eio))
+ (libraries eio_main capnp-rpc logs.fmt capnp-rpc-unix))
 
 (rule
  (targets echo_api.ml echo_api.mli)
@@ -615,7 +613,6 @@ let serve_cmd env =
 
 let () =
   exit @@ Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Cmd.eval (serve_cmd env)
 ```
 
@@ -661,7 +658,6 @@ let connect_cmd env =
 
 let () =
   exit @@ Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Cmd.eval (connect_cmd env)
 ```
 
@@ -866,7 +862,6 @@ let run_client ~net cap_file msg =
 
 let () =
   Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Switch.run @@ fun sw ->
   let net = env#net in
   start_server ~sw net;
@@ -910,7 +905,6 @@ We can use the new API like this:
 ```ocaml
 let () =
   Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Switch.run @@ fun sw ->
   let net = env#net in
   let root_uri = start_server ~sw net in
diff --git a/capnp-rpc-net.opam b/capnp-rpc-net.opam
index 4c5e47b6..a960c2c2 100644
--- a/capnp-rpc-net.opam
+++ b/capnp-rpc-net.opam
@@ -27,8 +27,8 @@ depends: [
   "asn1-combinators" {>= "0.2.0"}
   "x509" {>= "1.0.3"}
   "dune" {>= "3.16"}
-  "mirage-crypto" {>= "1.1.0"}
-  "mirage-crypto-rng" {>= "1.1.0"}
+  "mirage-crypto" {>= "1.2.0"}
+  "mirage-crypto-rng" {>= "1.2.0"}
 ]
 build: [
   ["dune" "build" "-p" name "-j" jobs]
diff --git a/capnp-rpc-unix.opam b/capnp-rpc-unix.opam
index 862fd9dc..4d524bd8 100644
--- a/capnp-rpc-unix.opam
+++ b/capnp-rpc-unix.opam
@@ -22,7 +22,7 @@ depends: [
   "dune" {>= "3.16"}
   "ipaddr" {>= "5.3.0" }
   "alcotest" {>= "1.6.0" & with-test}
-  "mirage-crypto-rng-eio" {>= "1.1.0" & with-test}
+  "mirage-crypto-rng" {>= "1.2.0"}
   "mdx" {>= "2.4.1" & with-test}
   "eio_main" {with-test}
   "eio" {>= "1.2"}
diff --git a/examples/pipelining/dune b/examples/pipelining/dune
index c3b83a62..a442e64c 100644
--- a/examples/pipelining/dune
+++ b/examples/pipelining/dune
@@ -1,6 +1,6 @@
 (executable
  (name main)
- (libraries eio_main capnp-rpc-unix mirage-crypto-rng-eio logs.fmt))
+ (libraries eio_main capnp-rpc-unix logs.fmt))
 
 (rule
  (targets echo_api.ml echo_api.mli)
diff --git a/examples/pipelining/main.ml b/examples/pipelining/main.ml
index f7591db3..5b759b73 100644
--- a/examples/pipelining/main.ml
+++ b/examples/pipelining/main.ml
@@ -33,7 +33,6 @@ let start_server ~sw ~delay net =
 
 let () =
   Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Switch.run @@ fun sw ->
   let delay = Eio.Time.Timeout.seconds env#mono_clock delay in
   let uri = start_server ~sw ~delay env#net in
diff --git a/examples/sturdy-refs-2/dune b/examples/sturdy-refs-2/dune
index cfebddc5..2f422404 100644
--- a/examples/sturdy-refs-2/dune
+++ b/examples/sturdy-refs-2/dune
@@ -1,6 +1,6 @@
 (executable
  (name main)
- (libraries eio_main capnp-rpc-unix mirage-crypto-rng-eio logs.fmt))
+ (libraries eio_main capnp-rpc-unix logs.fmt))
 
 (rule
  (targets api.ml api.mli)
diff --git a/examples/sturdy-refs-2/main.ml b/examples/sturdy-refs-2/main.ml
index 792e0ca1..59ceb8bf 100644
--- a/examples/sturdy-refs-2/main.ml
+++ b/examples/sturdy-refs-2/main.ml
@@ -28,7 +28,6 @@ let start_server ~sw net =
 (* $MDX part-begin=main *)
 let () =
   Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Switch.run @@ fun sw ->
   let net = env#net in
   let root_uri = start_server ~sw net in
diff --git a/examples/sturdy-refs-3/dune b/examples/sturdy-refs-3/dune
index cfebddc5..2f422404 100644
--- a/examples/sturdy-refs-3/dune
+++ b/examples/sturdy-refs-3/dune
@@ -1,6 +1,6 @@
 (executable
  (name main)
- (libraries eio_main capnp-rpc-unix mirage-crypto-rng-eio logs.fmt))
+ (libraries eio_main capnp-rpc-unix logs.fmt))
 
 (rule
  (targets api.ml api.mli)
diff --git a/examples/sturdy-refs-3/main.ml b/examples/sturdy-refs-3/main.ml
index 8b05ee30..dd80d619 100644
--- a/examples/sturdy-refs-3/main.ml
+++ b/examples/sturdy-refs-3/main.ml
@@ -39,7 +39,6 @@ let run_client ~net cap_file =
 
 let () =
   Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Switch.run @@ fun sw ->
   let net = env#net in
   let root_uri = start_server ~sw net in
diff --git a/examples/sturdy-refs-4/dune b/examples/sturdy-refs-4/dune
index 364c6ebb..d10029b5 100644
--- a/examples/sturdy-refs-4/dune
+++ b/examples/sturdy-refs-4/dune
@@ -1,6 +1,6 @@
 (executable
  (name main)
- (libraries eio_main capnp-rpc-unix mirage-crypto-rng-eio logs.fmt cmdliner))
+ (libraries eio_main capnp-rpc-unix logs.fmt cmdliner))
 
 (rule
  (targets api.ml api.mli)
diff --git a/examples/sturdy-refs-4/main.ml b/examples/sturdy-refs-4/main.ml
index 58aab194..e0270f38 100644
--- a/examples/sturdy-refs-4/main.ml
+++ b/examples/sturdy-refs-4/main.ml
@@ -100,5 +100,4 @@ let () =
   let doc = "a command-line interface for logger service" in
   let info = Cmd.info ~doc "logger-client" in
   exit @@ Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Cmd.eval @@ Cmd.group info (cmds env)
diff --git a/examples/sturdy-refs/dune b/examples/sturdy-refs/dune
index cfebddc5..2f422404 100644
--- a/examples/sturdy-refs/dune
+++ b/examples/sturdy-refs/dune
@@ -1,6 +1,6 @@
 (executable
  (name main)
- (libraries eio_main capnp-rpc-unix mirage-crypto-rng-eio logs.fmt))
+ (libraries eio_main capnp-rpc-unix logs.fmt))
 
 (rule
  (targets api.ml api.mli)
diff --git a/examples/sturdy-refs/main.ml b/examples/sturdy-refs/main.ml
index 1ed819a5..261efd39 100644
--- a/examples/sturdy-refs/main.ml
+++ b/examples/sturdy-refs/main.ml
@@ -44,7 +44,6 @@ let run_client ~net cap_file msg =
 
 let () =
   Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Switch.run @@ fun sw ->
   let net = env#net in
   start_server ~sw net;
diff --git a/examples/v3/dune b/examples/v3/dune
index c3b83a62..a442e64c 100644
--- a/examples/v3/dune
+++ b/examples/v3/dune
@@ -1,6 +1,6 @@
 (executable
  (name main)
- (libraries eio_main capnp-rpc-unix mirage-crypto-rng-eio logs.fmt))
+ (libraries eio_main capnp-rpc-unix logs.fmt))
 
 (rule
  (targets echo_api.ml echo_api.mli)
diff --git a/examples/v3/main.ml b/examples/v3/main.ml
index 23a9cb86..1dbb29eb 100644
--- a/examples/v3/main.ml
+++ b/examples/v3/main.ml
@@ -26,7 +26,6 @@ let start_server ~sw ~delay net =
 
 let () =
   Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Switch.run @@ fun sw ->
   let delay = Eio.Time.Timeout.seconds env#mono_clock delay in
   let uri = start_server ~sw ~delay env#net in
diff --git a/examples/v4/client.ml b/examples/v4/client.ml
index 4bc666af..748a1978 100644
--- a/examples/v4/client.ml
+++ b/examples/v4/client.ml
@@ -33,5 +33,4 @@ let connect_cmd env =
 
 let () =
   exit @@ Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Cmd.eval (connect_cmd env)
diff --git a/examples/v4/dune b/examples/v4/dune
index 64753b86..84bc067b 100644
--- a/examples/v4/dune
+++ b/examples/v4/dune
@@ -1,6 +1,6 @@
 (executables
  (names client server)
- (libraries eio_main capnp-rpc logs.fmt capnp-rpc-unix mirage-crypto-rng-eio))
+ (libraries eio_main capnp-rpc logs.fmt capnp-rpc-unix))
 
 (rule
  (targets echo_api.ml echo_api.mli)
diff --git a/examples/v4/server.ml b/examples/v4/server.ml
index 00e108b0..1fa26398 100644
--- a/examples/v4/server.ml
+++ b/examples/v4/server.ml
@@ -32,5 +32,4 @@ let serve_cmd env =
 
 let () =
   exit @@ Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Cmd.eval (serve_cmd env)
diff --git a/test-bin/calc.ml b/test-bin/calc.ml
index a8b7e83e..fed49b82 100644
--- a/test-bin/calc.ml
+++ b/test-bin/calc.ml
@@ -76,7 +76,6 @@ let cmds env = [serve_cmd env; connect_cmd env]
 
 let () =
   Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Fmt_tty.setup_std_outputs ();
   Logs.set_reporter reporter;
   Logs.set_level ~all:true (Some Logs.Info);
diff --git a/test-bin/dune b/test-bin/dune
index f51935d1..8220e654 100644
--- a/test-bin/dune
+++ b/test-bin/dune
@@ -1,4 +1,3 @@
 (executables
  (names calc calc_direct)
- (libraries testlib cmdliner astring logs.fmt fmt.tty capnp-rpc-unix eio_main
-            mirage-crypto-rng-eio))
+ (libraries testlib cmdliner astring logs.fmt fmt.tty capnp-rpc-unix eio_main))
diff --git a/test-bin/echo/dune b/test-bin/echo/dune
index 3cc3789b..29b59afb 100644
--- a/test-bin/echo/dune
+++ b/test-bin/echo/dune
@@ -1,6 +1,6 @@
 (executable
  (name echo_bench)
- (libraries eio_main capnp-rpc capnp-rpc-net capnp-rpc-unix mirage-crypto-rng-eio logs.fmt))
+ (libraries eio_main capnp-rpc capnp-rpc-net capnp-rpc-unix logs.fmt))
 
 (rule
  (targets echo_api.ml echo_api.mli)
diff --git a/test-bin/echo/echo_bench.ml b/test-bin/echo/echo_bench.ml
index d4a76452..6a06a55d 100755
--- a/test-bin/echo/echo_bench.ml
+++ b/test-bin/echo/echo_bench.ml
@@ -33,7 +33,6 @@ let start_server ~sw net =
 
 let () =
   Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   Switch.run ~name:"main" @@ fun sw ->
   let uri = start_server ~sw env#net in
   Fmt.pr "Connecting to echo service at: %a@." Uri.pp_hum uri;
diff --git a/test/dune b/test/dune
index b5824baa..67ba4905 100644
--- a/test/dune
+++ b/test/dune
@@ -2,4 +2,4 @@
  (package capnp-rpc-unix)
  (name test)
  (libraries capnp-rpc capnp-rpc-unix testlib logs.fmt
-   mirage-crypto-rng-eio testbed eio_main eio.mock))
+   testbed eio_main eio.mock))
diff --git a/test/test.ml b/test/test.ml
index 4aaae1a7..5a349ded 100644
--- a/test/test.ml
+++ b/test/test.ml
@@ -806,7 +806,6 @@ let rpc_tests ~net ~dir =
 
 let () =
   Eio_main.run @@ fun env ->
-  Mirage_crypto_rng_eio.run (module Mirage_crypto_rng.Fortuna) env @@ fun () ->
   (* Eio_unix.Ctf.with_tracing "/tmp/trace.ctf" @@ fun () -> *)
   Alcotest.run ~and_exit:false "capnp-rpc" [
     "eio", rpc_tests ~net:env#net ~dir:env#cwd;
diff --git a/unix/capnp_rpc_unix.ml b/unix/capnp_rpc_unix.ml
index 2124a291..74798a22 100644
--- a/unix/capnp_rpc_unix.ml
+++ b/unix/capnp_rpc_unix.ml
@@ -2,6 +2,8 @@ open Eio.Std
 
 module Log = Capnp_rpc.Debug.Log
 
+let () = Mirage_crypto_rng_unix.use_default ()
+
 module CapTP = Vat_network.CapTP
 module Vat = Vat_network.Vat
 module Network = Network
diff --git a/unix/dune b/unix/dune
index 57ef2fbc..5ac3d4de 100644
--- a/unix/dune
+++ b/unix/dune
@@ -1,4 +1,4 @@
 (library
  (name capnp_rpc_unix)
  (public_name capnp-rpc-unix)
- (libraries eio.unix astring capnp-rpc capnp-rpc-net fmt logs cmdliner cstruct extunix))
+ (libraries eio.unix astring capnp-rpc capnp-rpc-net fmt logs mirage-crypto-rng.unix cmdliner cstruct extunix))