diff --git a/src/definition.zig b/src/definition.zig
index c78dcdc..211402c 100644
--- a/src/definition.zig
+++ b/src/definition.zig
@@ -284,13 +284,13 @@ pub const Limits = struct {
     // 0x06 n:u64        ⇒ i64, {min n, max ?}, 1  ;; from threads proposal
     // 0x07 n:u64 m:u64  ⇒ i64, {min n, max m}, 1  ;; from threads proposal
 
-    const k_max_bytes_i32 = k_max_pages_i32 * MemoryDefinition.k_page_size;
-    const k_max_pages_i32 = std.math.powi(usize, 2, 16) catch unreachable;
+    pub const k_max_bytes_i32 = k_max_pages_i32 * MemoryDefinition.k_page_size;
+    pub const k_max_pages_i32 = std.math.powi(usize, 2, 16) catch unreachable;
 
     // Technically the max bytes should be maxInt(u64), but that is wayyy more memory than PCs have available and
     // is just a waste of virtual address space in the implementation. Instead we'll set the upper limit to 128GB.
-    const k_max_bytes_i64 = (1024 * 1024 * 1024 * 128);
-    const k_max_pages_i64 = k_max_bytes_i64 / MemoryDefinition.k_page_size;
+    pub const k_max_bytes_i64 = (1024 * 1024 * 1024 * 128);
+    pub const k_max_pages_i64 = k_max_bytes_i64 / MemoryDefinition.k_page_size;
 
     fn decode(reader: anytype) !Limits {
         const limit_type: u8 = try reader.readByte();
diff --git a/src/tests.zig b/src/tests.zig
index 5fd8b71..1901663 100644
--- a/src/tests.zig
+++ b/src/tests.zig
@@ -32,12 +32,26 @@ test "MemoryInstance.init" {
         const limits = Limits{
             .min = 0,
             .max = null,
-            .limit_type = 0,
+            .limit_type = 0, // i32 index type
+        };
+        var memory = MemoryInstance.init(limits, null);
+        defer memory.deinit();
+        try expectEqual(memory.limits.min, 0);
+        try expectEqual(memory.limits.max, Limits.k_max_pages_i32);
+        try expectEqual(memory.size(), 0);
+        try expectEqual(memory.mem.Internal.items.len, 0);
+    }
+
+    {
+        const limits = Limits{
+            .min = 0,
+            .max = null,
+            .limit_type = 4, // i64 index type
         };
         var memory = MemoryInstance.init(limits, null);
         defer memory.deinit();
         try expectEqual(memory.limits.min, 0);
-        try expectEqual(memory.limits.max, MemoryInstance.k_max_pages);
+        try expectEqual(memory.limits.max, Limits.k_max_pages_i64);
         try expectEqual(memory.size(), 0);
         try expectEqual(memory.mem.Internal.items.len, 0);
     }
@@ -70,8 +84,8 @@ test "MemoryInstance.Internal.grow" {
         try expectEqual(memory.size(), 1);
         try expectEqual(memory.grow(1), true);
         try expectEqual(memory.size(), 2);
-        try expectEqual(memory.grow(MemoryInstance.k_max_pages - memory.size()), true);
-        try expectEqual(memory.size(), MemoryInstance.k_max_pages);
+        try expectEqual(memory.grow(Limits.k_max_pages_i32 - memory.size()), true);
+        try expectEqual(memory.size(), Limits.k_max_pages_i32);
     }
 
     {
@@ -104,8 +118,8 @@ test "MemoryInstance.Internal.growAbsolute" {
         try expectEqual(memory.size(), 1);
         try expectEqual(memory.growAbsolute(5), true);
         try expectEqual(memory.size(), 5);
-        try expectEqual(memory.growAbsolute(MemoryInstance.k_max_pages), true);
-        try expectEqual(memory.size(), MemoryInstance.k_max_pages);
+        try expectEqual(memory.growAbsolute(Limits.k_max_pages_i32), true);
+        try expectEqual(memory.size(), Limits.k_max_pages_i32);
     }
 
     {