diff --git a/cfg/ruby.cfg b/cfg/ruby.cfg
new file mode 100644
index 000000000..6c9ead349
--- /dev/null
+++ b/cfg/ruby.cfg
@@ -0,0 +1,53 @@
+<?xml version="1.0"?>
+<def format="2">
+  <!-- Ruby C API. see https://docs.ruby-lang.org/en/2.5.0/extension_rdoc.html -->
+  <!-- void rb_define_const(VALUE klass, const char *name, VALUE val)  -->
+  <function name="rb_define_const">
+    <leak-ignore/>
+    <noreturn>false</noreturn>
+    <returnValue type="void"/>
+    <arg nr="1">
+      <not-uninit/>
+    </arg>
+    <arg nr="2">
+      <not-null/>
+      <strz/>
+    </arg>
+    <arg nr="3">
+      <not-uninit/>
+    </arg>
+  </function>
+  <!-- void rb_define_method(VALUE klass, const char *name, VALUE (*func)(ANYARGS), int argc) -->
+  <function name="rb_define_method">
+    <leak-ignore/>
+    <noreturn>false</noreturn>
+    <returnValue type="void"/>
+    <arg nr="1">
+      <not-uninit/>
+    </arg>
+    <arg nr="2">
+      <not-null/>
+      <strz/>
+    </arg>
+    <arg nr="4">
+      <not-bool/>
+      <not-uninit/>
+    </arg>
+  </function>
+  <!-- void rb_raise(rb_eRuntimeError, const char *fmt, …)  -->
+  <function name="rb_raise">
+    <leak-ignore/>
+    <noreturn>false</noreturn>
+    <returnValue type="void"/>
+    <arg nr="1">
+      <not-uninit/>
+    </arg>
+    <arg nr="2">
+      <formatstr/>
+      <not-null/>
+    </arg>
+    <arg nr="any">
+      <not-uninit/>
+    </arg>
+  </function>
+</def>