diff --git a/crates/lune-std-ffi/src/data/box_data/mod.rs b/crates/lune-std-ffi/src/data/box_data/mod.rs
index 88ab7bae..70ce3b38 100644
--- a/crates/lune-std-ffi/src/data/box_data/mod.rs
+++ b/crates/lune-std-ffi/src/data/box_data/mod.rs
@@ -50,7 +50,8 @@ impl BoxData {
         if self.size() > FFI_BOX_PRINT_MAX_LENGTH * 2 {
             return String::from("length limit exceed");
         }
-        let mut buff: String = String::with_capacity(self.size() * 2);
+        let mut buff: String = String::with_capacity(self.size() * 2 + 2);
+        buff.push_str("0x");
         for value in self.data.iter() {
             buff.push_str(format!("{:x}", value.to_be()).as_str());
         }
diff --git a/crates/lune-std-ffi/src/data/callable_data.rs b/crates/lune-std-ffi/src/data/callable_data.rs
index 2e95a27b..47f47953 100644
--- a/crates/lune-std-ffi/src/data/callable_data.rs
+++ b/crates/lune-std-ffi/src/data/callable_data.rs
@@ -124,6 +124,11 @@ impl CallableData {
         }
     }
 
+    // Stringify for pretty-print, with hex format address
+    pub fn stringify(&self) -> String {
+        format!("0x{:x}", self.code.as_ptr() as usize)
+    }
+
     pub unsafe fn call(&self, result: LuaValue, args: LuaMultiValue) -> LuaResult<()> {
         let arg_len = self.arg_info_list.len();
         // Optimization: use sized caller when possible
@@ -178,5 +183,8 @@ impl LuaUserData for CallableData {
                 unsafe { this.call(result, args) }
             },
         );
+        methods.add_meta_method(LuaMetaMethod::ToString, |_lua, this, ()| {
+            Ok(this.stringify())
+        });
     }
 }
diff --git a/crates/lune-std-ffi/src/data/closure_data.rs b/crates/lune-std-ffi/src/data/closure_data.rs
index 1a5dfca6..26595d1c 100644
--- a/crates/lune-std-ffi/src/data/closure_data.rs
+++ b/crates/lune-std-ffi/src/data/closure_data.rs
@@ -118,6 +118,11 @@ impl ClosureData {
 
         Ok(closure_data)
     }
+
+    // Stringify for pretty-print, with hex format address
+    pub fn stringify(&self) -> String {
+        format!("0x{:x}", unsafe { self.get_inner_pointer() } as usize)
+    }
 }
 
 impl FfiData for ClosureData {
@@ -148,5 +153,8 @@ impl LuaUserData for ClosureData {
             association::set(lua, REF_INNER, &ref_data, &this)?;
             Ok(ref_data)
         });
+        methods.add_meta_method(LuaMetaMethod::ToString, |_lua, this, ()| {
+            Ok(this.stringify())
+        });
     }
 }
diff --git a/crates/lune-std-ffi/src/data/lib_data.rs b/crates/lune-std-ffi/src/data/lib_data.rs
index 9c92ce59..b8819f9b 100644
--- a/crates/lune-std-ffi/src/data/lib_data.rs
+++ b/crates/lune-std-ffi/src/data/lib_data.rs
@@ -13,13 +13,19 @@ const LIB_REF_FLAGS: u8 = RefFlag::Offsetable.value()
     | RefFlag::Function.value();
 
 // Runtime dynamic loaded libraries
-pub struct LibData(Library);
+pub struct LibData {
+    name: String,
+    lib: Library,
+}
 
 impl LibData {
     // Open library then return library handle
     pub fn new(libname: String) -> LuaResult<Self> {
-        match Library::open(libname) {
-            Ok(t) => Ok(Self(t)),
+        match Library::open(&libname) {
+            Ok(t) => Ok(Self {
+                lib: t,
+                name: libname.clone(),
+            }),
             Err(err) => Err(err.into_lua_err()),
         }
     }
@@ -32,7 +38,7 @@ impl LibData {
     ) -> LuaResult<LuaAnyUserData<'lua>> {
         let lib = this.borrow::<LibData>()?;
         let sym = unsafe {
-            lib.0
+            lib.lib
                 .symbol::<*const ()>(name.as_str())
                 .map_err(LuaError::external)?
         };
@@ -44,6 +50,10 @@ impl LibData {
 
         Ok(ffi_ref)
     }
+
+    pub fn stringify(&self) -> String {
+        self.name.clone()
+    }
 }
 
 impl LuaUserData for LibData {
@@ -51,5 +61,8 @@ impl LuaUserData for LibData {
         methods.add_function("find", |lua, (this, name): (LuaAnyUserData, String)| {
             LibData::find_symbol(lua, this, name)
         });
+        methods.add_meta_method(LuaMetaMethod::ToString, |_lua, this, ()| {
+            Ok(this.stringify())
+        });
     }
 }
diff --git a/crates/lune-std-ffi/src/data/ref_data/mod.rs b/crates/lune-std-ffi/src/data/ref_data/mod.rs
index 2c15d5ec..3de26137 100644
--- a/crates/lune-std-ffi/src/data/ref_data/mod.rs
+++ b/crates/lune-std-ffi/src/data/ref_data/mod.rs
@@ -117,7 +117,7 @@ impl RefData {
 
     // Stringify for pretty-print, with hex format address
     pub fn stringify(&self) -> String {
-        format!("{:x}", **self.ptr as usize)
+        format!("0x{:x}", **self.ptr as usize)
     }
 }
 
diff --git a/tests/ffi/README.md b/tests/ffi/README.md
index f42576b6..47d2779f 100644
--- a/tests/ffi/README.md
+++ b/tests/ffi/README.md
@@ -1,4 +1,6 @@
-# tests/ffi
+<!-- markdownlint-disable MD036 -->
+
+# `tests/ffi`
 
 ## Requirements
 
@@ -25,7 +27,9 @@ gcc for library compiling (for external-\*)
 **Pretty Print**
 
 - [x] [arr](./pretty_print/arr.luau)
-- [ ] [box](./pretty_print/box.luau)
+- [ ] [box](./pretty_print/box.luau) Need assertion
+- [ ] [ref](./pretty_print/ref.luau) Need assertion
+- [ ] [lib](./pretty_print/lib.luau) Need assertion
 - [x] [fn](./pretty_print/fn.luau)
 - [x] [ptr](./pretty_print/ptr.luau)
 - [x] [struct](./pretty_print/struct.luau)