diff --git a/examples/mixed-test/BUILD.bazel b/examples/mixed-test/BUILD.bazel
new file mode 100644
index 00000000..5bdeaa20
--- /dev/null
+++ b/examples/mixed-test/BUILD.bazel
@@ -0,0 +1,15 @@
+load("@build_bazel_rules_ios//rules:app.bzl", "ios_application")
+
+ios_application(
+    name = "mixed-test",
+    srcs = glob([
+        "*.swift",
+        "*.m",
+        "*.h",
+    ]),
+    bundle_id = "com.example.mixed-app",
+    families = [
+        "iphone",
+    ],
+    minimum_os_version = "12.0",
+)
diff --git a/examples/mixed-test/ObjcFile.h b/examples/mixed-test/ObjcFile.h
new file mode 100644
index 00000000..8cb17abd
--- /dev/null
+++ b/examples/mixed-test/ObjcFile.h
@@ -0,0 +1,22 @@
+//
+//  objcHeader.h
+//  mixed-test
+//
+//  Created by Oscar Bonilla on 7/23/18.
+//  Copyright © 2018 Oscar Bonilla. All rights reserved.
+//
+
+#ifndef objcHeader_h
+#define objcHeader_h
+
+#import <Foundation/Foundation.h>
+
+@interface ObjcObject : NSObject
+
+@property (strong, nonatomic) id someProperty;
+
+- (void) someMethod;
+
+@end
+
+#endif /* objcHeader_h */
diff --git a/examples/mixed-test/ObjcFile.m b/examples/mixed-test/ObjcFile.m
new file mode 100644
index 00000000..758d627a
--- /dev/null
+++ b/examples/mixed-test/ObjcFile.m
@@ -0,0 +1,30 @@
+//
+//  objcFile.m
+//  mixed-test
+//
+//  Created by Oscar Bonilla on 7/23/18.
+//  Copyright © 2018 Oscar Bonilla. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+
+#import "ObjcFile.h"
+#import "mixed_test-Swift.h"
+
+@implementation ObjcObject
+
+- (void) someMethod {
+    NSLog(@"SomeMethod Ran");
+}
+
+- (void) someOtherMethod {
+    SwiftObj *myOb = [SwiftObj new];
+    NSLog(@"myOb.someProperty: %@", myOb.someProperty);
+    myOb.someProperty = @"Hello World";
+    NSLog(@"MyOb.someProperty: %@", myOb.someProperty);
+    NSString * retString = [myOb someFunctionWithSomeArg:@"Arg"];
+    NSLog(@"RetString: %@", retString);
+}
+
+@end
+
diff --git a/examples/mixed-test/SwiftObj.swift b/examples/mixed-test/SwiftObj.swift
new file mode 100644
index 00000000..06bf15a8
--- /dev/null
+++ b/examples/mixed-test/SwiftObj.swift
@@ -0,0 +1,27 @@
+//
+//  mixed_test.swift
+//  mixed-test
+//
+//  Created by Oscar Bonilla on 7/23/18.
+//  Copyright © 2018 Oscar Bonilla. All rights reserved.
+//
+
+public class SwiftObj : NSObject {
+
+    @objc public var someProperty: NSString = "Some Initializer Val"
+
+    override init() {}
+
+    @objc public func someFunction(someArg:AnyObject) -> String {
+        let returnVal = "You sent me \(someArg)"
+        return returnVal
+    }
+
+    func someOtherFunction() {
+        let objcObject: ObjcObject = ObjcObject()
+        objcObject.someProperty = "Hello World"
+        print(objcObject.someProperty!)
+        objcObject.someMethod()
+    }
+
+}
diff --git a/examples/mixed-test/mixed-test-Bridging-Header.h b/examples/mixed-test/mixed-test-Bridging-Header.h
new file mode 100644
index 00000000..32223ed5
--- /dev/null
+++ b/examples/mixed-test/mixed-test-Bridging-Header.h
@@ -0,0 +1,5 @@
+//
+//  Use this file to import your target's public headers that you would like to expose to Swift.
+//
+
+#import "ObjcFile.h"
diff --git a/rules/library.bzl b/rules/library.bzl
index 1ac9d73a..382dcc3c 100644
--- a/rules/library.bzl
+++ b/rules/library.bzl
@@ -47,6 +47,9 @@ write_file = rule(
     doc = "Writes out a file verbatim",
 )
 
+def _normalize_module_name(name):
+    return name.replace("-", "_")
+
 def _extend_modulemap_impl(ctx):
     args = ctx.actions.args()
     args.add("""
@@ -90,7 +93,7 @@ def write_modulemap(name, library_tools, umbrella_header = None, public_headers
     basename = "{}.modulemap".format(name)
     destination = paths.join(name + "-modulemap", basename)
     if not module_name:
-        module_name = name
+        fail("module_name not set, this is a bug, please file an issue at https://github.com/ob/rules_ios/issues")
     content = """\
 module {module_name} {{
     umbrella header "{umbrella_header}"
@@ -117,7 +120,7 @@ def write_umbrella_header(name, library_tools, public_headers = [], private_head
     basename = "{name}-umbrella.h".format(name = name)
     destination = paths.join(name + "-modulemap", basename)
     if not module_name:
-        module_name = name
+        fail("module_name not set, this is a bug, please file an issue at https://github.com/ob/rules_ios/issues")
     content = """\
 #ifdef __OBJC__
 #    import <Foundation/Foundation.h>
@@ -243,7 +246,7 @@ def apple_library(name, library_tools = {}, export_private_headers = True, names
         else:
             fail("Unable to compile %s in apple_framework %s" % (f, name))
 
-    module_name = kwargs.pop("module_name", name)
+    module_name = _normalize_module_name(kwargs.pop("module_name", name))
     namespace = module_name if namespace_is_module_name else name
     module_map = kwargs.pop("module_map", None)
     cc_copts = kwargs.pop("cc_copts", [])