diff --git a/pkg/macos/foundation.zig b/pkg/macos/foundation.zig
index ca0536b8c..8b29ccfb3 100644
--- a/pkg/macos/foundation.zig
+++ b/pkg/macos/foundation.zig
@@ -2,6 +2,7 @@ pub const c = @import("foundation/c.zig");
 pub usingnamespace @import("foundation/array.zig");
 pub usingnamespace @import("foundation/base.zig");
 pub usingnamespace @import("foundation/dictionary.zig");
+pub usingnamespace @import("foundation/number.zig");
 pub usingnamespace @import("foundation/string.zig");
 pub usingnamespace @import("foundation/type.zig");
 pub usingnamespace @import("foundation/url.zig");
diff --git a/pkg/macos/foundation/c.zig b/pkg/macos/foundation/c.zig
new file mode 100644
index 000000000..9bd571adb
--- /dev/null
+++ b/pkg/macos/foundation/c.zig
@@ -0,0 +1,3 @@
+pub usingnamespace @cImport({
+    @cInclude("CoreFoundation/CoreFoundation.h");
+});
diff --git a/pkg/macos/foundation/dictionary.zig b/pkg/macos/foundation/dictionary.zig
index 6d9c6bd9e..8d74a90f1 100644
--- a/pkg/macos/foundation/dictionary.zig
+++ b/pkg/macos/foundation/dictionary.zig
@@ -2,11 +2,12 @@ const std = @import("std");
 const assert = std.debug.assert;
 const Allocator = std.mem.Allocator;
 const foundation = @import("../foundation.zig");
+const c = @import("c.zig");
 
 pub const Dictionary = opaque {
     pub fn create(
-        keys: ?[]*const anyopaque,
-        values: ?[]*const anyopaque,
+        keys: ?[]?*const anyopaque,
+        values: ?[]?*const anyopaque,
     ) Allocator.Error!*Dictionary {
         if (keys != null or values != null) {
             assert(keys != null);
@@ -14,14 +15,14 @@ pub const Dictionary = opaque {
             assert(keys.?.len == values.?.len);
         }
 
-        return CFDictionaryCreate(
+        return @intToPtr(?*Dictionary, @ptrToInt(c.CFDictionaryCreate(
             null,
-            if (keys) |slice| slice.ptr else null,
-            if (values) |slice| slice.ptr else null,
-            if (keys) |slice| slice.len else 0,
-            &kCFTypeDictionaryKeyCallBacks,
-            &kCFTypeDictionaryValueCallBacks,
-        ) orelse Allocator.Error.OutOfMemory;
+            @ptrCast([*c]?*const anyopaque, if (keys) |slice| slice.ptr else null),
+            @ptrCast([*c]?*const anyopaque, if (values) |slice| slice.ptr else null),
+            @intCast(c.CFIndex, if (keys) |slice| slice.len else 0),
+            &c.kCFTypeDictionaryKeyCallBacks,
+            &c.kCFTypeDictionaryValueCallBacks,
+        ))) orelse Allocator.Error.OutOfMemory;
     }
 
     pub fn release(self: *Dictionary) void {
@@ -29,36 +30,29 @@ pub const Dictionary = opaque {
     }
 
     pub fn getCount(self: *Dictionary) usize {
-        return CFDictionaryGetCount(self);
+        return @intCast(usize, c.CFDictionaryGetCount(@ptrCast(c.CFDictionaryRef, self)));
     }
 
-    pub extern "c" fn CFDictionaryCreate(
-        allocator: ?*anyopaque,
-        keys: ?[*]*const anyopaque,
-        values: ?[*]*const anyopaque,
-        num_values: usize,
-        key_callbacks: *const anyopaque,
-        value_callbacks: *const anyopaque,
-    ) ?*Dictionary;
-    pub extern "c" fn CFDictionaryGetCount(*Dictionary) usize;
-
-    extern "c" var kCFTypeDictionaryKeyCallBacks: anyopaque;
-    extern "c" var kCFTypeDictionaryValueCallBacks: anyopaque;
+    pub fn getValue(self: *Dictionary, comptime V: type, key: ?*const anyopaque) ?*V {
+        return @intToPtr(?*V, @ptrToInt(c.CFDictionaryGetValue(
+            @ptrCast(c.CFDictionaryRef, self),
+            key,
+        )));
+    }
 };
 
-// Just used for a test
-extern "c" var kCFURLIsPurgeableKey: *const anyopaque;
-
 test "dictionary" {
     const testing = std.testing;
 
     const str = try foundation.String.createWithBytes("hello", .unicode, false);
     defer str.release();
 
-    var keys = [_]*const anyopaque{kCFURLIsPurgeableKey};
-    var values = [_]*const anyopaque{str};
+    var keys = [_]?*const anyopaque{c.kCFURLIsPurgeableKey};
+    var values = [_]?*const anyopaque{str};
     const dict = try Dictionary.create(&keys, &values);
     defer dict.release();
 
     try testing.expectEqual(@as(usize, 1), dict.getCount());
+    try testing.expect(dict.getValue(foundation.String, c.kCFURLIsPurgeableKey) != null);
+    try testing.expect(dict.getValue(foundation.String, c.kCFURLIsVolumeKey) == null);
 }
diff --git a/pkg/macos/foundation/number.zig b/pkg/macos/foundation/number.zig
new file mode 100644
index 000000000..289c9e8f1
--- /dev/null
+++ b/pkg/macos/foundation/number.zig
@@ -0,0 +1,79 @@
+const std = @import("std");
+const Allocator = std.mem.Allocator;
+const foundation = @import("../foundation.zig");
+const c = @import("c.zig");
+
+pub const Number = opaque {
+    pub fn create(
+        comptime type_: NumberType,
+        value: *const type_.ValueType(),
+    ) Allocator.Error!*Number {
+        return @intToPtr(?*Number, @ptrToInt(c.CFNumberCreate(
+            null,
+            @enumToInt(type_),
+            value,
+        ))) orelse Allocator.Error.OutOfMemory;
+    }
+
+    pub fn getValue(self: *Number, comptime t: NumberType, ptr: *t.ValueType()) bool {
+        return c.CFNumberGetValue(
+            @ptrCast(c.CFNumberRef, self),
+            @enumToInt(t),
+            ptr,
+        ) == 1;
+    }
+
+    pub fn release(self: *Number) void {
+        c.CFRelease(self);
+    }
+};
+
+pub const NumberType = enum(c.CFNumberType) {
+    sint8 = c.kCFNumberSInt8Type,
+    sint16 = c.kCFNumberSInt16Type,
+    sint32 = c.kCFNumberSInt32Type,
+    sint64 = c.kCFNumberSInt64Type,
+    float32 = c.kCFNumberFloat32Type,
+    float64 = c.kCFNumberFloat64Type,
+    char = c.kCFNumberCharType,
+    short = c.kCFNumberShortType,
+    int = c.kCFNumberIntType,
+    long = c.kCFNumberLongType,
+    long_long = c.kCFNumberLongLongType,
+    float = c.kCFNumberFloatType,
+    double = c.kCFNumberDoubleType,
+    cf_index = c.kCFNumberCFIndexType,
+    ns_integer = c.kCFNumberNSIntegerType,
+    cg_float = c.kCFNumberCGFloatType,
+
+    pub fn ValueType(self: NumberType) type {
+        return switch (self) {
+            .sint8 => i8,
+            .sint16 => i16,
+            .sint32 => i32,
+            .sint64 => i64,
+            .float32 => f32,
+            .float64 => f64,
+            .char => u8,
+            .short => c_short,
+            .int => c_int,
+            .long => c_long,
+            .long_long => c_longlong,
+            .float => f32,
+            .double => f64,
+            else => unreachable, // TODO
+        };
+    }
+};
+
+test {
+    const testing = std.testing;
+
+    const inner: i8 = 42;
+    const v = try Number.create(.sint8, &inner);
+    defer v.release();
+
+    var result: i8 = undefined;
+    try testing.expect(v.getValue(.sint8, &result));
+    try testing.expectEqual(result, inner);
+}