diff --git a/parse-resolver-runtime/assoc.cc b/parse-resolver-runtime/assoc.cc
index 8486b58..b1ed9f0 100644
--- a/parse-resolver-runtime/assoc.cc
+++ b/parse-resolver-runtime/assoc.cc
@@ -317,6 +317,10 @@ void ecsact_meta_system_assoc_capabilities(
 		return;
 	}
 
+	if(out_capabilities_count) {
+		*out_capabilities_count = static_cast<int32_t>(info->caps.size());
+	}
+
 	for(int32_t i = 0; max_capabilities_count > i; ++i) {
 		if(i >= info->caps.size()) {
 			break;
diff --git a/test/BUILD.bazel b/test/BUILD.bazel
index 5c1dda9..e0575fc 100644
--- a/test/BUILD.bazel
+++ b/test/BUILD.bazel
@@ -59,6 +59,22 @@ cc_test(
     ],
 )
 
+cc_test(
+    name = "assoc_capabilities",
+    srcs = ["assoc_capabilities.cc"],
+    copts = copts,
+    data = [
+        "assoc_capabilities.ecsact",
+    ],
+    deps = [
+        ":test_lib",
+        "@ecsact_interpret",
+        "@bazel_sundry//bazel_sundry:runfiles",
+        "@googletest//:gtest",
+        "@googletest//:gtest_main",
+    ],
+)
+
 cc_test(
     name = "field_indexing",
     srcs = ["field_indexing.cc"],
diff --git a/test/MODULE.bazel b/test/MODULE.bazel
index 326782c..0dd0e95 100644
--- a/test/MODULE.bazel
+++ b/test/MODULE.bazel
@@ -14,6 +14,11 @@ git_override(
     remote = "https://github.com/hedronvision/bazel-compile-commands-extractor.git",
 )
 
+local_path_override(
+    module_name = "ecsact_runtime",
+    path = "../../ecsact_runtime",
+)
+
 llvm = use_extension("@toolchains_llvm//toolchain/extensions:llvm.bzl", "llvm", dev_dependency = True)
 llvm.toolchain(llvm_version = "17.0.6")
 use_repo(llvm, "llvm_toolchain")
diff --git a/test/assoc_capabilities.cc b/test/assoc_capabilities.cc
new file mode 100644
index 0000000..731ae32
--- /dev/null
+++ b/test/assoc_capabilities.cc
@@ -0,0 +1,76 @@
+
+#include "gtest/gtest.h"
+
+#include "ecsact/runtime/meta.hh"
+#include "ecsact/runtime/dynamic.h"
+#include "test_lib.hh"
+
+using ecsact::meta::get_field_type;
+
+class AssocCapabilities : public testing::Test {
+public:
+	ecsact_package_id pkg_id;
+
+protected:
+	void SetUp() override {
+		auto errs = ecsact_interpret_test_files({"assoc_capabilities.ecsact"});
+		ASSERT_EQ(errs.size(), 0) //
+			<< "Expected no errors. Instead got: " << errs[0].error_message << "\n";
+		pkg_id = ecsact::meta::get_package_ids().at(0);
+	}
+
+	void TearDown() override {
+		// ecsact_destroy_package(pkg_id);
+	}
+};
+
+TEST_F(AssocCapabilities, GeneralReads) {
+	auto example_comp = get_component_by_name(pkg_id, "Example");
+	ASSERT_TRUE(example_comp);
+
+	auto comp = get_component_by_name(pkg_id, "AssocComp");
+	ASSERT_TRUE(comp);
+
+	auto sys = get_system_by_name(pkg_id, "ReadwriteSystem");
+	auto assoc_ids = ecsact::meta::system_assoc_ids(*sys);
+	ASSERT_EQ(assoc_ids.size(), 1);
+
+	auto caps = ecsact::meta::system_assoc_capabilities(*sys, assoc_ids.at(0));
+	ASSERT_EQ(caps.size(), 1);
+
+	ASSERT_EQ(
+		caps.at(0).first,
+		ecsact_id_cast<ecsact_component_like_id>(*example_comp)
+	);
+	ASSERT_EQ(caps.at(0).second, ECSACT_SYS_CAP_READWRITE);
+}
+
+TEST_F(AssocCapabilities, RemovesExists) {
+	auto example_comp = get_component_by_name(pkg_id, "Example");
+	ASSERT_TRUE(example_comp);
+
+	auto tag_comp = get_component_by_name(pkg_id, "MyTag");
+	ASSERT_TRUE(tag_comp);
+
+	auto comp = get_component_by_name(pkg_id, "AssocComp");
+	ASSERT_TRUE(comp);
+
+	auto sys = get_system_by_name(pkg_id, "RemovesSystem");
+	auto assoc_ids = ecsact::meta::system_assoc_ids(*sys);
+	ASSERT_EQ(assoc_ids.size(), 1);
+
+	auto assoc_caps =
+		ecsact::meta::system_assoc_capabilities(*sys, assoc_ids.at(0));
+
+	// order isn't guaranteed
+	for(auto&& [comp_id, caps] : assoc_caps) {
+		if(comp_id == ecsact_id_cast<ecsact_component_like_id>(*tag_comp)) {
+			ASSERT_EQ(caps, ECSACT_SYS_CAP_INCLUDE);
+		} else if(comp_id ==
+							ecsact_id_cast<ecsact_component_like_id>(*example_comp)) {
+			ASSERT_EQ(caps, ECSACT_SYS_CAP_REMOVES);
+		} else {
+			ASSERT_TRUE(false) << "unknown comp id";
+		}
+	}
+}
diff --git a/test/assoc_capabilities.ecsact b/test/assoc_capabilities.ecsact
new file mode 100644
index 0000000..ce8438f
--- /dev/null
+++ b/test/assoc_capabilities.ecsact
@@ -0,0 +1,19 @@
+package eval.assoc_capabilities;
+
+component MyTag;
+component Example { i32 num; }
+component AssocComp { Example.num hello; }
+
+system ReadwriteSystem {
+  readwrite AssocComp with hello {
+    readwrite Example;
+  }
+}
+
+system RemovesSystem {
+  readwrite AssocComp with hello {
+    include MyTag;
+    removes Example;
+  }
+}
+