diff --git a/.cirrus.yml b/.cirrus.yml
index 73d23f3e..63e6a83f 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -20,7 +20,7 @@ freebsd_task:
 
   test_mirage_script: eval `opam env` && ./.test-mirage.sh
 
-freebsd_eio_task:
+freebsd_ocaml_5_task:
   pkg_install_script: pkg install -y ocaml-opam gmake pkgconf bash
 
   ocaml_script:
@@ -28,6 +28,6 @@ freebsd_eio_task:
     - opam env
 
   pin_packages_script:
-    - opam install -y --deps-only -t ./mirage-crypto.opam ./mirage-crypto-rng.opam ./mirage-crypto-rng-eio.opam
+    - opam install -y --deps-only -t ./mirage-crypto.opam ./mirage-crypto-rng.opam ./mirage-crypto-rng-eio.opam ./mirage-crypto-rng-miou.opam
 
-  test_script: opam exec -- dune runtest -p mirage-crypto,mirage-crypto-rng,mirage-crypto-rng-eio
+  test_script: opam exec -- dune runtest -p mirage-crypto,mirage-crypto-rng,mirage-crypto-rng-eio,mirage-crypto-rng-miou
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index c1a8bb0e..6535165c 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -24,6 +24,7 @@ jobs:
           opam-local-packages: |
             *.opam
             !mirage-crypto-rng-eio.opam
+            !mirage-crypto-rng-miou.opam
           ocaml-compiler: ${{ matrix.ocaml-version }}
 
       - name: Install dependencies
@@ -35,8 +36,8 @@ jobs:
       - name: Test
         run: opam exec -- dune runtest -p mirage-crypto,mirage-crypto-rng,mirage-crypto-rng-lwt,mirage-crypto-rng-mirage,mirage-crypto-pk,mirage-crypto-ec,mirage-crypto-rng-async
 
-  build-test-unix-eio:
-    name : Unix (eio)
+  build-test-ocaml-5:
+    name : Tests with OCaml 5
 
     strategy:
       fail-fast: false
@@ -57,13 +58,14 @@ jobs:
             mirage-crypto.opam
             mirage-crypto-rng.opam
             mirage-crypto-rng-eio.opam
+            mirage-crypto-rng-miou.opam
           ocaml-compiler: ${{ matrix.ocaml-version }}
 
       - name: Install dependencies
-        run: opam install --deps-only -t mirage-crypto mirage-crypto-rng mirage-crypto-rng-eio
+        run: opam install --deps-only -t mirage-crypto mirage-crypto-rng mirage-crypto-rng-eio mirage-crypto-rng-miou
 
       - name: Build
-        run: opam exec -- dune build -p mirage-crypto,mirage-crypto-rng,mirage-crypto-rng-eio
+        run: opam exec -- dune build -p mirage-crypto,mirage-crypto-rng,mirage-crypto-rng-eio,mirage-crypto-rng-miou
 
       - name: Test
-        run: opam exec -- dune runtest -p mirage-crypto,mirage-crypto-rng,mirage-crypto-rng-eio
+        run: opam exec -- dune runtest -p mirage-crypto,mirage-crypto-rng,mirage-crypto-rng-eio,mirage-crypto-rng-miou
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index 4f97944f..43b28cf3 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -28,6 +28,7 @@ jobs:
             *.opam
             !mirage-crypto-rng-async.opam
             !mirage-crypto-rng-eio.opam
+            !mirage-crypto-rng-miou.opam
           ocaml-compiler: ${{ matrix.ocaml-version }}
 
       - name: Install dependencies