diff --git a/cli/Cargo.toml b/cli/Cargo.toml
index 7cc9111..f4ca128 100644
--- a/cli/Cargo.toml
+++ b/cli/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "wikit"
-version = "0.3.0"
+version = "0.3.1"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
diff --git a/core/src/lib.rs b/core/src/lib.rs
index 784d3f8..a7cae83 100644
--- a/core/src/lib.rs
+++ b/core/src/lib.rs
@@ -9,3 +9,7 @@ pub mod index;
 pub mod wikit;
 pub mod cache;
 pub mod crypto;
+
+#[test]
+fn test_core_debug() {
+}
diff --git a/core/src/wikit.rs b/core/src/wikit.rs
index 9d50d08..fbb5f07 100644
--- a/core/src/wikit.rs
+++ b/core/src/wikit.rs
@@ -121,14 +121,16 @@ impl WikitHead {
             namesz: be_u16 >>
             name: map_res!(take!(namesz),
                 |x: &[u8]| -> AnyResult<String> {
-                    let name = String::from_utf8(x.to_vec()).context(elog!("cannot get name"))?;
+                    let name = String::from_utf8(x.to_vec())
+                        .context(elog!("failed to get wikti dictionary name"))?;
                     Ok(name)
                 }
             ) >>
             descsz: be_u16 >>
             desc: map_res!(take!(descsz),
                 |x: &[u8]| -> AnyResult<String> {
-                    let desc = String::from_utf8(x.to_vec()).context(elog!("cannot get desc"))?;
+                    let desc = String::from_utf8(x.to_vec())
+                        .context(elog!("failed to get dictionary description"))?;
                     Ok(desc)
                 }
             ) >>
@@ -169,7 +171,13 @@ impl WikitHead {
                 }
             )
         );
-        Ok(r.unwrap().1)
+
+        match r {
+            Ok(r) => Ok(r.1),
+            Err(e) => {
+                Err(WikitError::new(format!("failed to parse WikitHead: {:?}", e)))
+            }
+        }
     }
 }
 
@@ -232,7 +240,7 @@ impl RemoteDictionary {
 ///
 /// if version is 0x01, then the follwoing layout is
 ///
-///      hdrsz:2
+///      hdrsz:4
 ///      namesz:2
 ///      name:namesz
 ///      descsz:2
@@ -324,7 +332,7 @@ impl LocalDictionary {
         writer.write(&LATEST_WIKIT_FMT_VERSION.to_be_bytes()[..])?;
         // hdrsz
         let hdrsz_pos = writer.seek(SeekFrom::Current(0))?;
-        writer.seek(SeekFrom::Current(2))?;
+        writer.seek(SeekFrom::Current(4))?;
         // namesz and name
         let namesz = conf.name.len() as u16;
         writer.write(&namesz.to_be_bytes()[..])?;
@@ -357,7 +365,7 @@ impl LocalDictionary {
         writer.write(&style.as_bytes()[..])?;
 
         // save header size
-        let hdrsz = writer.seek(SeekFrom::Current(0))? as u16;
+        let hdrsz = writer.seek(SeekFrom::Current(0))? as u32;
         writer.seek(SeekFrom::Start(hdrsz_pos))?;
         writer.write(&hdrsz.to_be_bytes()[..])?;
         writer.seek(SeekFrom::Start(hdrsz as u64))?;
@@ -425,9 +433,9 @@ impl LocalDictionary {
             return Err(WikitError::new("Wrong wikit version"));
         }
 
-        let mut hdrsz = [0u8; 2];
+        let mut hdrsz = [0u8; 4];
         file.read_exact(&mut hdrsz)?;
-        let hdrsz = u16::from_be_bytes(hdrsz) as usize;
+        let hdrsz = u32::from_be_bytes(hdrsz) as usize;
 
         let hdrbuf = file.bytes().take(hdrsz).filter_map(Result::ok).collect::<Vec<u8>>();
         if hdrbuf.len() != hdrsz {
diff --git a/desktop/src-tauri/Cargo.toml b/desktop/src-tauri/Cargo.toml
index 8b1be62..f7b97bc 100644
--- a/desktop/src-tauri/Cargo.toml
+++ b/desktop/src-tauri/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "wikit-desktop"
-version = "0.1.0-beta.1"
+version = "0.1.0-beta.2"
 description = "Wikit Desktop - A universal dictionary for human"
 authors = ["ikey4u <pwnkeeper@gmail.com>"]
 license = "MIT"
diff --git a/makefile b/makefile
index e81a6e3..1b8bb29 100644
--- a/makefile
+++ b/makefile
@@ -8,3 +8,6 @@ release:
 
 cli:
 	@cargo install --path cli
+
+dbgcore:
+	@cargo test test_core_debug -- --nocapture