diff --git a/src/body.rs b/src/body.rs
index 9966213..4e84305 100644
--- a/src/body.rs
+++ b/src/body.rs
@@ -1,12 +1,12 @@
+use http_1::HeaderMap;
+use http_body_1::Frame;
+use pin_project_lite::pin_project;
+use std::str::FromStr;
 use std::{
     pin::Pin,
     task::{Context, Poll},
 };
 
-use http_1::HeaderMap;
-use http_body_1::Frame;
-use pin_project_lite::pin_project;
-
 // --- http-body 0.4 to http-body 1.0 ---
 
 pin_project! {
@@ -48,7 +48,9 @@ where
         }
 
         match self.as_mut().project().body.poll_trailers(cx) {
-            Poll::Ready(Ok(Some(trailers))) => Poll::Ready(Some(Ok(Frame::trailers(http02_headermap_to_http1(trailers))))),
+            Poll::Ready(Ok(Some(trailers))) => Poll::Ready(Some(Ok(Frame::trailers(
+                http02_headermap_to_http1(trailers),
+            )))),
             Poll::Ready(Ok(None)) => Poll::Ready(None),
             Poll::Ready(Err(err)) => Poll::Ready(Some(Err(err))),
             Poll::Pending => Poll::Pending,
@@ -143,7 +145,9 @@ where
 
             match ready!(this.body.poll_frame(cx)) {
                 Some(Ok(frame)) => match frame.into_trailers() {
-                    Ok(trailers) => break Poll::Ready(Ok(Some(http1_headermap_to_http02(trailers)))),
+                    Ok(trailers) => {
+                        break Poll::Ready(Ok(Some(http1_headermap_to_http02(trailers))))
+                    }
                     // we might get a trailers frame on next poll
                     // so loop and try again
                     Err(_frame) => {}
@@ -171,41 +175,109 @@ where
 }
 
 fn http1_headermap_to_http02(h: http_1::HeaderMap) -> http_02::HeaderMap {
-    unsafe {
-        std::mem::transmute::<http_1::HeaderMap, http_02::HeaderMap>(h)
+    let mut hm = http_02::HeaderMap::new();
+    for (k, v) in h {
+        hm.insert(
+            http_02::HeaderName::from_str(k.unwrap().as_str()).unwrap(),
+            http_02::HeaderValue::from_bytes(v.as_ref()).unwrap(),
+        );
     }
+    hm
 }
 
 fn http02_headermap_to_http1(h: http_02::HeaderMap) -> http_1::HeaderMap {
-    unsafe {
-        std::mem::transmute::<http_02::HeaderMap, http_1::HeaderMap>(h)
+    let mut hm = http_1::HeaderMap::new();
+    for (k, v) in h {
+        hm.insert(
+            http_1::HeaderName::from_str(k.unwrap().as_str()).unwrap(),
+            http_1::HeaderValue::from_bytes(v.as_ref()).unwrap(),
+        );
     }
+    hm
 }
 
 pub fn http1_request_to_http02<B>(r: http_1::Request<B>) -> http_02::Request<B> {
     let (head, body) = r.into_parts();
-    unsafe {
-        http_02::Request::from_parts(std::mem::transmute::<_, http_02::request::Parts>(head), body)
+    let mut build = http_02::request::Builder::new()
+        .method(head.method.as_str())
+        .uri(format!("{}", head.uri))
+        .version(match head.version {
+            http_1::version::Version::HTTP_09 => http_02::version::Version::HTTP_09,
+            http_1::version::Version::HTTP_10 => http_02::version::Version::HTTP_10,
+            http_1::version::Version::HTTP_11 => http_02::version::Version::HTTP_11,
+            http_1::version::Version::HTTP_2 => http_02::version::Version::HTTP_2,
+            http_1::version::Version::HTTP_3 => http_02::version::Version::HTTP_3,
+            _ => panic!("unknown version"),
+        });
+    for (k, v) in head.headers {
+        build = build.header(k.unwrap().as_str(), v.as_ref())
     }
+    // for v in head.extension {
+    //     build = build.extension(v)
+    // }
+    build.body(body).unwrap()
 }
 
 pub fn http1_response_to_http02<B>(r: http_1::Response<B>) -> http_02::Response<B> {
     let (head, body) = r.into_parts();
-    unsafe {
-        http_02::Response::from_parts(std::mem::transmute::<_, http_02::response::Parts>(head), body)
+    let mut build = http_02::response::Builder::new()
+        .status(head.status.as_u16())
+        .version(match head.version {
+            http_1::version::Version::HTTP_09 => http_02::version::Version::HTTP_09,
+            http_1::version::Version::HTTP_10 => http_02::version::Version::HTTP_10,
+            http_1::version::Version::HTTP_11 => http_02::version::Version::HTTP_11,
+            http_1::version::Version::HTTP_2 => http_02::version::Version::HTTP_2,
+            http_1::version::Version::HTTP_3 => http_02::version::Version::HTTP_3,
+            _ => panic!("unknown version"),
+        });
+    for (k, v) in head.headers {
+        build = build.header(k.unwrap().as_str(), v.as_ref())
     }
+    // for v in head.extension {
+    //     build = build.extension(v)
+    // }
+    build.body(body).unwrap()
 }
 
 pub fn http02_request_to_http1<B>(r: http_02::Request<B>) -> http_1::Request<B> {
     let (head, body) = r.into_parts();
-    unsafe {
-        http_1::Request::from_parts(std::mem::transmute::<_, http_1::request::Parts>(head), body)
+    let mut build = http_1::request::Builder::new()
+        .method(head.method.as_str())
+        .uri(format!("{}", head.uri))
+        .version(match head.version {
+            http_02::version::Version::HTTP_09 => http_1::version::Version::HTTP_09,
+            http_02::version::Version::HTTP_10 => http_1::version::Version::HTTP_10,
+            http_02::version::Version::HTTP_11 => http_1::version::Version::HTTP_11,
+            http_02::version::Version::HTTP_2 => http_1::version::Version::HTTP_2,
+            http_02::version::Version::HTTP_3 => http_1::version::Version::HTTP_3,
+            _ => panic!("unknown version"),
+        });
+    for (k, v) in head.headers {
+        build = build.header(k.unwrap().as_str(), v.as_ref())
     }
+    // for v in head.extension {
+    //     build = build.extension(v)
+    // }
+    build.body(body).unwrap()
 }
 
 pub fn http02_response_to_http1<B>(r: http_02::Response<B>) -> http_1::Response<B> {
     let (head, body) = r.into_parts();
-    unsafe {
-        http_1::Response::from_parts(std::mem::transmute::<_, http_1::response::Parts>(head), body)
+    let mut build = http_1::response::Builder::new()
+        .status(head.status.as_u16())
+        .version(match head.version {
+            http_02::version::Version::HTTP_09 => http_1::version::Version::HTTP_09,
+            http_02::version::Version::HTTP_10 => http_1::version::Version::HTTP_10,
+            http_02::version::Version::HTTP_11 => http_1::version::Version::HTTP_11,
+            http_02::version::Version::HTTP_2 => http_1::version::Version::HTTP_2,
+            http_02::version::Version::HTTP_3 => http_1::version::Version::HTTP_3,
+            _ => panic!("unknown version"),
+        });
+    for (k, v) in head.headers {
+        build = build.header(k.unwrap().as_str(), v.as_ref())
     }
-}
\ No newline at end of file
+    // for v in head.extension {
+    //     build = build.extension(v)
+    // }
+    build.body(body).unwrap()
+}
diff --git a/src/lib.rs b/src/lib.rs
index 483ca3d..d3c8502 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -138,9 +138,9 @@ cfg_service! {
 
 mod body;
 
-pub use body::{HttpBody04ToHttpBody1, HttpBody1ToHttpBody04};
-pub use body::{http1_request_to_http02, http1_response_to_http02};
 pub use body::{http02_request_to_http1, http02_response_to_http1};
+pub use body::{http1_request_to_http02, http1_response_to_http02};
+pub use body::{HttpBody04ToHttpBody1, HttpBody1ToHttpBody04};
 
 #[cfg(test)]
 mod tests;