diff --git a/crates/proc-macro-api/src/transport/codec.rs b/crates/proc-macro-api/src/transport/codec.rs
deleted file mode 100644
index c9afad260a..0000000000
--- a/crates/proc-macro-api/src/transport/codec.rs
+++ /dev/null
@@ -1,15 +0,0 @@
-//! Protocol codec
-
-use std::io;
-
-use serde::de::DeserializeOwned;
-
-use crate::transport::framing::Framing;
-
-pub mod json;
-pub mod postcard;
-
-pub trait Codec: Framing {
-    fn encode<T: serde::Serialize>(msg: &T) -> io::Result<Self::Buf>;
-    fn decode<T: DeserializeOwned>(buf: &mut Self::Buf) -> io::Result<T>;
-}
diff --git a/crates/proc-macro-api/src/transport/framing.rs b/crates/proc-macro-api/src/transport/framing.rs
deleted file mode 100644
index 56c3b68e8c..0000000000
--- a/crates/proc-macro-api/src/transport/framing.rs
+++ /dev/null
@@ -1,14 +0,0 @@
-//! Protocol framing
-
-use std::io::{self, BufRead, Write};
-
-pub trait Framing {
-    type Buf: Default + Send + Sync;
-
-    fn read<'a, R: BufRead + ?Sized>(
-        inp: &mut R,
-        buf: &'a mut Self::Buf,
-    ) -> io::Result<Option<&'a mut Self::Buf>>;
-
-    fn write<W: Write + ?Sized>(out: &mut W, buf: &Self::Buf) -> io::Result<()>;
-}