diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 66d81e3..5c55588 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -45,6 +45,10 @@ jobs:
         run: |
           opam exec -- dune runtest
 
+      - name: Integration tests
+        run: |
+          opam exec -- dune build @integration
+
       - name: Format
         run: |
           opam exec -- dune build @fmt
diff --git a/README.md b/README.md
index a2e0048..832f8f5 100644
--- a/README.md
+++ b/README.md
@@ -30,6 +30,19 @@ $ opam install object
 
 And add `object` to your project's `dune-project` or `*.opam` files.
 
+## Tests
+
+The tests for `object` are split between:
+ * Unit tests in `test/unit` that build in-memory representations of binaries
+   and test they can be parsed correctly. They can be run using
+   `dune build @runtest`.
+ * Integration tests in `test/integration` that use the system toolchain to
+   build binaries and check they can be parsed correctly. These tests rely more
+   on specific versions of the toolchain that match GitHub CI runners. They can
+   be run using `dune build @integration`.
+
+Both suites can be run together with `dune build @run-all-tests`.
+
 ## Documentation
 
  * Documentation on [ocaml.org](https://ocaml.org/p/object)
diff --git a/dune b/dune
new file mode 100644
index 0000000..ab9402a
--- /dev/null
+++ b/dune
@@ -0,0 +1,8 @@
+; dune build @run-all-tests: alias that runs the unit tests (@runtest)
+; and the integration tests (@integration) together.
+
+(alias
+ (name run-all-tests)
+ (deps
+  (alias_rec runtest)
+  (alias_rec integration)))
diff --git a/dune-project b/dune-project
index 171f24f..fffbf5c 100644
--- a/dune-project
+++ b/dune-project
@@ -1,4 +1,4 @@
-(lang dune 3.9)
+(lang dune 3.23)
 (name object)
 (generate_opam_files true)
 (cram enable)
@@ -14,8 +14,8 @@
  (synopsis "A unified interface for reading and writing object file formats")
  (description "A unified interface for reading and writing object file formats")
  (depends
-    (ocaml (>= 4.08))
-    (integers (>= 0.8.0))
-    (cmdliner :with-test)
+    (ocaml (>= 4.14))
+    (integers (>= 0.8))
+    (cmdliner (and :with-test (>= 2.1)))
     (alcotest :with-test)
     (ocamlformat (and :with-dev-setup (= 0.29.0)))))
diff --git a/example/dune b/example/dune
index 510c280..836a509 100644
--- a/example/dune
+++ b/example/dune
@@ -1,4 +1,3 @@
 (executables
- (public_names oc_objdump generic_objdump ocnm octool oclipo ocfile)
  (names oc_objdump generic_objdump ocnm octool oclipo ocfile)
  (libraries integers object unix cmdliner))
diff --git a/object.opam b/object.opam
index 7eecf05..abbd9aa 100644
--- a/object.opam
+++ b/object.opam
@@ -10,10 +10,10 @@ tags: ["elf" "object" "mach-o" "pe" "coff"]
 homepage: "https://github.com/tmcgilchrist/object"
 bug-reports: "https://github.com/tmcgilchrist/object/issues"
 depends: [
-  "dune" {>= "3.9"}
-  "ocaml" {>= "4.08"}
-  "integers" {>= "0.8.0"}
-  "cmdliner" {with-test}
+  "dune" {>= "3.23"}
+  "ocaml" {>= "4.14"}
+  "integers" {>= "0.8"}
+  "cmdliner" {with-test & >= "2.1"}
   "alcotest" {with-test}
   "ocamlformat" {with-dev-setup & = "0.29.0"}
   "odoc" {with-doc}
@@ -33,3 +33,5 @@ build: [
   ]
 ]
 dev-repo: "git+https://github.com/tmcgilchrist/object.git"
+x-maintenance-intent: ["(latest)"]
+available: arch != "ppc64"
diff --git a/object.opam.template b/object.opam.template
new file mode 100644
index 0000000..f8be4f0
--- /dev/null
+++ b/object.opam.template
@@ -0,0 +1 @@
+available: arch != "ppc64"
diff --git a/test/dune b/test/integration/dune
similarity index 74%
rename from test/dune
rename to test/integration/dune
index 7e93ef7..438d7ba 100644
--- a/test/dune
+++ b/test/integration/dune
@@ -1,109 +1,94 @@
-(test
- (name test_object)
- (libraries object integers alcotest))
+; Integration tests: build real object files and executables with the system
+; toolchain, then verify the object library can read the details back. They
+; also compare the example tools against the platform's native tools.
+;
+
+(executables
+ (names
+  test_pe_real
+  test_fat
+  test_macho_arm64
+  test_macho_amd64
+  test_elf_arm64)
+ (libraries object integers alcotest cmdliner))
+
+; Fixtures produced by the local toolchain.
 
-(test
- (name test_leb128)
- (libraries object integers alcotest))
+(rule
+ (deps hello_world.c)
+ (target hello_world)
+ (enabled_if
+  (or
+   (= %{system} "linux")
+   (= %{system} "macosx")))
+ (action
+  (run cc %{deps} -o %{target})))
 
-(test
- (name test_pe)
- (libraries object integers alcotest))
+; A Windows PE/COFF object built by cross-compiling a header-free C source.
 
-; Exercise the reader against a real toolchain-produced COFF object, when a
-; cross-compiler that targets Windows PE/COFF is available.
+(rule
+ (deps hello_pe.c)
+ (target hello_pe.obj)
+ (enabled_if
+  (or
+   (= %{bin-available:clang} true)
+   (= %{bin-available:x86_64-w64-mingw32-gcc} true)))
+ (action
+  (system
+   "clang --target=x86_64-pc-windows-msvc -c %{deps} -o %{target} || x86_64-w64-mingw32-gcc -c %{deps} -o %{target}")))
+
+; Reader acceptance tests against the real binaries above.
 
-(test
- (name test_pe_real)
- (build_if
+(rule
+ (alias integration)
+ (enabled_if
   (or
    (= %{bin-available:clang} true)
    (= %{bin-available:x86_64-w64-mingw32-gcc} true)))
- (libraries object integers alcotest cmdliner)
- (deps hello_pe.obj)
  (action
   (run %{exe:test_pe_real.exe} --binary %{dep:hello_pe.obj})))
 
-(test
- (name test_fat)
- (build_if
+(rule
+ (alias integration)
+ (enabled_if
   (and
    (= %{system} "macosx")
    (= %{architecture} "arm64")))
- (libraries object integers alcotest)
  (action
   (run %{exe:test_fat.exe})))
 
-(test
- (name test_macho_arm64)
+(rule
+ (alias integration)
  (deps hello_world)
- (build_if
+ (enabled_if
   (and
    (= %{system} "macosx")
    (= %{architecture} "arm64")))
- (libraries object integers alcotest cmdliner)
  (action
   (run %{exe:test_macho_arm64.exe} --binary %{dep:hello_world})))
 
-(test
- (name test_macho_amd64)
+(rule
+ (alias integration)
  (deps hello_world)
- (build_if
+ (enabled_if
   (and
    (= %{system} "macosx")
    (= %{architecture} "amd64")))
- (libraries object integers alcotest cmdliner)
  (action
   (run %{exe:test_macho_amd64.exe} --binary %{dep:hello_world})))
 
-(test
- (name test_elf_arm64)
- (libraries object integers alcotest cmdliner)
- (build_if
+(rule
+ (alias integration)
+ (deps hello_world)
+ (enabled_if
   (and
    (= %{system} "linux")
    (= %{architecture} "arm64")))
  (action
   (run %{exe:test_elf_arm64.exe} --binary %{dep:hello_world})))
 
-; Provide a plain C program to inspect
-
-(rule
- (deps hello_world.c)
- (target hello_world)
- (enabled_if
-  (or
-   (= %{system} "linux")
-   (= %{system} "macosx")))
- (action
-  (run cc %{deps} -o %{target})))
-
-; Provide a C program with DWARF 5 debug information to inspect.
-
-(rule
- (deps hello_world.c)
- (target hello_world_dwarf_5)
- (enabled_if
-  (or
-   (= %{system} "linux")
-   (= %{system} "macosx")))
- (action
-  (run cc -gdwarf-5 %{deps} -o %{target})))
-
-; A Windows PE/COFF object built by cross-compiling a header-free C source.
-
-(rule
- (deps hello_pe.c)
- (target hello_pe.obj)
- (enabled_if
-  (or
-   (= %{bin-available:clang} true)
-   (= %{bin-available:x86_64-w64-mingw32-gcc} true)))
- (action
-  (system
-   "clang --target=x86_64-pc-windows-msvc -c %{deps} -o %{target} || x86_64-w64-mingw32-gcc -c %{deps} -o %{target}")))
-
-; FAT binary testing - compare our tools with system tools
+; FAT binary testing - compare our example tools with the system tools on a
+; known multi-arch system binary.
 
 (rule
  (target xcrun.otool-f.expected)
@@ -118,7 +103,7 @@
 
 (rule
  (target xcrun.otool-f.output)
- (deps %{bin:octool})
+ (deps %{exe:../../example/octool.exe})
  (enabled_if
   (and
    (= %{system} "macosx")
@@ -126,10 +111,10 @@
  (action
   (with-stdout-to
    %{target}
-   (run %{bin:octool} -f /usr/bin/xcrun))))
+   (run %{exe:../../example/octool.exe} -f /usr/bin/xcrun))))
 
 (rule
- (alias runtest)
+ (alias integration)
  (enabled_if
   (and
    (= %{system} "macosx")
@@ -150,7 +135,7 @@
 
 (rule
  (target xcrun.lipo-info.output)
- (deps %{bin:oclipo})
+ (deps %{exe:../../example/oclipo.exe})
  (enabled_if
   (and
    (= %{system} "macosx")
@@ -158,10 +143,10 @@
  (action
   (with-stdout-to
    %{target}
-   (run %{bin:oclipo} --info /usr/bin/xcrun))))
+   (run %{exe:../../example/oclipo.exe} --info /usr/bin/xcrun))))
 
 (rule
- (alias runtest)
+ (alias integration)
  (enabled_if
   (and
    (= %{system} "macosx")
@@ -182,7 +167,7 @@
 
 (rule
  (target xcrun.lipo-archs.output)
- (deps %{bin:oclipo})
+ (deps %{exe:../../example/oclipo.exe})
  (enabled_if
   (and
    (= %{system} "macosx")
@@ -190,10 +175,10 @@
  (action
   (with-stdout-to
    %{target}
-   (run %{bin:oclipo} --archs /usr/bin/xcrun))))
+   (run %{exe:../../example/oclipo.exe} --archs /usr/bin/xcrun))))
 
 (rule
- (alias runtest)
+ (alias integration)
  (enabled_if
   (and
    (= %{system} "macosx")
@@ -214,7 +199,7 @@
 
 (rule
  (target xcrun.lipo-verify_arch.output)
- (deps %{bin:oclipo})
+ (deps %{exe:../../example/oclipo.exe})
  (enabled_if
   (and
    (= %{system} "macosx")
@@ -223,7 +208,7 @@
   (with-stdout-to
    %{target}
    (run
-    %{bin:oclipo}
+    %{exe:../../example/oclipo.exe}
     --verify_arch
     x86_64
     --verify_arch
@@ -231,7 +216,7 @@
     /usr/bin/xcrun))))
 
 (rule
- (alias runtest)
+ (alias integration)
  (enabled_if
   (and
    (= %{system} "macosx")
@@ -263,7 +248,7 @@
    (run %{bin:file} /usr/bin/xcrun))))
 
 (rule
- (alias runtest)
+ (alias integration)
  (enabled_if
   (and
    (= %{system} "macosx")
@@ -284,7 +269,7 @@
 
 (rule
  (target xcrun.otool-l.output)
- (deps %{bin:octool})
+ (deps %{exe:../../example/octool.exe})
  (enabled_if
   (and
    (= %{system} "macosx")
@@ -292,10 +277,10 @@
  (action
   (with-stdout-to
    %{target}
-   (run %{bin:octool} -l /usr/bin/xcrun))))
+   (run %{exe:../../example/octool.exe} -l /usr/bin/xcrun))))
 
 (rule
- (alias runtest)
+ (alias integration)
  (enabled_if
   (and
    (= %{system} "macosx")
diff --git a/test/hello_pe.c b/test/integration/hello_pe.c
similarity index 100%
rename from test/hello_pe.c
rename to test/integration/hello_pe.c
diff --git a/test/hello_world.c b/test/integration/hello_world.c
similarity index 100%
rename from test/hello_world.c
rename to test/integration/hello_world.c
diff --git a/test/test_elf_arm64.ml b/test/integration/test_elf_arm64.ml
similarity index 100%
rename from test/test_elf_arm64.ml
rename to test/integration/test_elf_arm64.ml
diff --git a/test/test_fat.ml b/test/integration/test_fat.ml
similarity index 100%
rename from test/test_fat.ml
rename to test/integration/test_fat.ml
diff --git a/test/test_macho_amd64.ml b/test/integration/test_macho_amd64.ml
similarity index 100%
rename from test/test_macho_amd64.ml
rename to test/integration/test_macho_amd64.ml
diff --git a/test/test_macho_arm64.ml b/test/integration/test_macho_arm64.ml
similarity index 100%
rename from test/test_macho_arm64.ml
rename to test/integration/test_macho_arm64.ml
diff --git a/test/test_pe_real.ml b/test/integration/test_pe_real.ml
similarity index 100%
rename from test/test_pe_real.ml
rename to test/integration/test_pe_real.ml
diff --git a/test/unit/dune b/test/unit/dune
new file mode 100644
index 0000000..6d541b6
--- /dev/null
+++ b/test/unit/dune
@@ -0,0 +1,5 @@
+; Unit tests: exercise the library against in-memory and embedded data.
+
+(tests
+ (names test_object test_leb128 test_pe)
+ (libraries object integers alcotest))
diff --git a/test/test_leb128.ml b/test/unit/test_leb128.ml
similarity index 100%
rename from test/test_leb128.ml
rename to test/unit/test_leb128.ml
diff --git a/test/test_object.ml b/test/unit/test_object.ml
similarity index 100%
rename from test/test_object.ml
rename to test/unit/test_object.ml
diff --git a/test/test_pe.ml b/test/unit/test_pe.ml
similarity index 100%
rename from test/test_pe.ml
rename to test/unit/test_pe.ml