diff --git a/pbjson-build/src/generator/enumeration.rs b/pbjson-build/src/generator/enumeration.rs
index 0eadc39..c833484 100644
--- a/pbjson-build/src/generator/enumeration.rs
+++ b/pbjson-build/src/generator/enumeration.rs
@@ -109,10 +109,9 @@ fn write_visitor<W: Write>(
 {indent}    where
 {indent}        E: serde::de::Error,
 {indent}    {{
-{indent}        use std::convert::TryFrom;
 {indent}        i32::try_from(v)
 {indent}            .ok()
-{indent}            .and_then({rust_type}::from_i32)
+{indent}            .and_then(|x| x.try_into().ok())
 {indent}            .ok_or_else(|| {{
 {indent}                serde::de::Error::invalid_value(serde::de::Unexpected::Signed(v), &self)
 {indent}            }})
@@ -122,10 +121,9 @@ fn write_visitor<W: Write>(
 {indent}    where
 {indent}        E: serde::de::Error,
 {indent}    {{
-{indent}        use std::convert::TryFrom;
 {indent}        i32::try_from(v)
 {indent}            .ok()
-{indent}            .and_then({rust_type}::from_i32)
+{indent}            .and_then(|x| x.try_into().ok())
 {indent}            .ok_or_else(|| {{
 {indent}                serde::de::Error::invalid_value(serde::de::Unexpected::Unsigned(v), &self)
 {indent}            }})
diff --git a/pbjson-build/src/generator/message.rs b/pbjson-build/src/generator/message.rs
index 4834010..4203554 100644
--- a/pbjson-build/src/generator/message.rs
+++ b/pbjson-build/src/generator/message.rs
@@ -208,10 +208,10 @@ fn write_decode_variant<W: Write>(
     path: &TypePath,
     writer: &mut W,
 ) -> Result<()> {
-    writeln!(writer, "{}::from_i32({})", resolver.rust_type(path), value)?;
+    writeln!(writer, "{}::try_from({})", resolver.rust_type(path), value)?;
     write!(
         writer,
-        "{}.ok_or_else(|| serde::ser::Error::custom(format!(\"Invalid variant {{}}\", {})))",
+        "{}.map_err(|_| serde::ser::Error::custom(format!(\"Invalid variant {{}}\", {})))",
         Indent(indent),
         value
     )