diff --git a/crates/arroyo-rpc/src/api_types/connections.rs b/crates/arroyo-rpc/src/api_types/connections.rs
index 9c6750dbf..2dd05b671 100644
--- a/crates/arroyo-rpc/src/api_types/connections.rs
+++ b/crates/arroyo-rpc/src/api_types/connections.rs
@@ -8,6 +8,7 @@ use std::fmt::{Display, Formatter};
 use std::sync::Arc;
 
 use crate::df::{ArroyoSchema, ArroyoSchemaRef};
+use arroyo_types::ArroyoExtensionType;
 use utoipa::{IntoParams, ToSchema};
 
 #[derive(Serialize, Deserialize, Clone, Debug, ToSchema)]
@@ -124,33 +125,40 @@ pub struct SourceField {
 
 impl From<SourceField> for Field {
     fn from(f: SourceField) -> Self {
-        let t = match f.field_type.r#type {
+        let (t, ext) = match f.field_type.r#type {
             FieldType::Primitive(pt) => match pt {
-                PrimitiveType::Int32 => DataType::Int32,
-                PrimitiveType::Int64 => DataType::Int64,
-                PrimitiveType::UInt32 => DataType::UInt32,
-                PrimitiveType::UInt64 => DataType::UInt64,
-                PrimitiveType::F32 => DataType::Float32,
-                PrimitiveType::F64 => DataType::Float64,
-                PrimitiveType::Bool => DataType::Boolean,
-                PrimitiveType::String => DataType::Utf8,
-                PrimitiveType::Bytes => DataType::Binary,
-                PrimitiveType::UnixMillis => DataType::Timestamp(TimeUnit::Millisecond, None),
-                PrimitiveType::UnixMicros => DataType::Timestamp(TimeUnit::Microsecond, None),
-                PrimitiveType::UnixNanos => DataType::Timestamp(TimeUnit::Nanosecond, None),
-                PrimitiveType::DateTime => DataType::Timestamp(TimeUnit::Microsecond, None),
-                PrimitiveType::Json => DataType::Utf8,
+                PrimitiveType::Int32 => (DataType::Int32, None),
+                PrimitiveType::Int64 => (DataType::Int64, None),
+                PrimitiveType::UInt32 => (DataType::UInt32, None),
+                PrimitiveType::UInt64 => (DataType::UInt64, None),
+                PrimitiveType::F32 => (DataType::Float32, None),
+                PrimitiveType::F64 => (DataType::Float64, None),
+                PrimitiveType::Bool => (DataType::Boolean, None),
+                PrimitiveType::String => (DataType::Utf8, None),
+                PrimitiveType::Bytes => (DataType::Binary, None),
+                PrimitiveType::UnixMillis => {
+                    (DataType::Timestamp(TimeUnit::Millisecond, None), None)
+                }
+                PrimitiveType::UnixMicros => {
+                    (DataType::Timestamp(TimeUnit::Microsecond, None), None)
+                }
+                PrimitiveType::UnixNanos => (DataType::Timestamp(TimeUnit::Nanosecond, None), None),
+                PrimitiveType::DateTime => (DataType::Timestamp(TimeUnit::Microsecond, None), None),
+                PrimitiveType::Json => (DataType::Utf8, Some(ArroyoExtensionType::JSON)),
             },
-            FieldType::Struct(s) => DataType::Struct(Fields::from(
-                s.fields
-                    .into_iter()
-                    .map(|t| t.into())
-                    .collect::<Vec<Field>>(),
-            )),
-            FieldType::List(t) => DataType::List(Arc::new((*t).into())),
+            FieldType::Struct(s) => (
+                DataType::Struct(Fields::from(
+                    s.fields
+                        .into_iter()
+                        .map(|t| t.into())
+                        .collect::<Vec<Field>>(),
+                )),
+                None,
+            ),
+            FieldType::List(t) => (DataType::List(Arc::new((*t).into())), None),
         };
 
-        Field::new(f.field_name, t, f.nullable)
+        ArroyoExtensionType::add_metadata(ext, Field::new(f.field_name, t, f.nullable))
     }
 }
 
@@ -158,26 +166,31 @@ impl TryFrom<Field> for SourceField {
     type Error = String;
 
     fn try_from(f: Field) -> Result<Self, Self::Error> {
-        let field_type = match f.data_type() {
-            DataType::Boolean => FieldType::Primitive(PrimitiveType::Bool),
-            DataType::Int32 => FieldType::Primitive(PrimitiveType::Int32),
-            DataType::Int64 => FieldType::Primitive(PrimitiveType::Int64),
-            DataType::UInt32 => FieldType::Primitive(PrimitiveType::UInt32),
-            DataType::UInt64 => FieldType::Primitive(PrimitiveType::UInt64),
-            DataType::Float32 => FieldType::Primitive(PrimitiveType::F32),
-            DataType::Float64 => FieldType::Primitive(PrimitiveType::F64),
-            DataType::Binary | DataType::LargeBinary => FieldType::Primitive(PrimitiveType::Bytes),
-            DataType::Timestamp(TimeUnit::Millisecond, _) => {
+        let field_type = match (f.data_type(), ArroyoExtensionType::from_map(f.metadata())) {
+            (DataType::Boolean, None) => FieldType::Primitive(PrimitiveType::Bool),
+            (DataType::Int32, None) => FieldType::Primitive(PrimitiveType::Int32),
+            (DataType::Int64, None) => FieldType::Primitive(PrimitiveType::Int64),
+            (DataType::UInt32, None) => FieldType::Primitive(PrimitiveType::UInt32),
+            (DataType::UInt64, None) => FieldType::Primitive(PrimitiveType::UInt64),
+            (DataType::Float32, None) => FieldType::Primitive(PrimitiveType::F32),
+            (DataType::Float64, None) => FieldType::Primitive(PrimitiveType::F64),
+            (DataType::Binary, None) | (DataType::LargeBinary, None) => {
+                FieldType::Primitive(PrimitiveType::Bytes)
+            }
+            (DataType::Timestamp(TimeUnit::Millisecond, _), None) => {
                 FieldType::Primitive(PrimitiveType::UnixMillis)
             }
-            DataType::Timestamp(TimeUnit::Microsecond, _) => {
+            (DataType::Timestamp(TimeUnit::Microsecond, _), None) => {
                 FieldType::Primitive(PrimitiveType::UnixMicros)
             }
-            DataType::Timestamp(TimeUnit::Nanosecond, _) => {
+            (DataType::Timestamp(TimeUnit::Nanosecond, _), None) => {
                 FieldType::Primitive(PrimitiveType::UnixNanos)
             }
-            DataType::Utf8 => FieldType::Primitive(PrimitiveType::String),
-            DataType::Struct(fields) => {
+            (DataType::Utf8, None) => FieldType::Primitive(PrimitiveType::String),
+            (DataType::Utf8, Some(ArroyoExtensionType::JSON)) => {
+                FieldType::Primitive(PrimitiveType::Json)
+            }
+            (DataType::Struct(fields), None) => {
                 let fields: Result<_, String> = fields
                     .into_iter()
                     .map(|f| (**f).clone().try_into())
@@ -190,7 +203,7 @@ impl TryFrom<Field> for SourceField {
 
                 FieldType::Struct(st)
             }
-            DataType::List(item) => FieldType::List(Box::new((**item).clone().try_into()?)),
+            (DataType::List(item), None) => FieldType::List(Box::new((**item).clone().try_into()?)),
             dt => {
                 return Err(format!("Unsupported data type {:?}", dt));
             }
diff --git a/crates/arroyo-rpc/src/lib.rs b/crates/arroyo-rpc/src/lib.rs
index 65abbf1f7..126c5492b 100644
--- a/crates/arroyo-rpc/src/lib.rs
+++ b/crates/arroyo-rpc/src/lib.rs
@@ -156,7 +156,7 @@ pub fn primitive_to_sql(primitive_type: PrimitiveType) -> &'static str {
         | PrimitiveType::UnixMicros
         | PrimitiveType::UnixNanos
         | PrimitiveType::DateTime => "TIMESTAMP",
-        PrimitiveType::Json => "JSONB",
+        PrimitiveType::Json => "JSON",
     }
 }
 
diff --git a/crates/arroyo-types/src/lib.rs b/crates/arroyo-types/src/lib.rs
index 062c97fe7..d872e2f04 100644
--- a/crates/arroyo-types/src/lib.rs
+++ b/crates/arroyo-types/src/lib.rs
@@ -629,7 +629,10 @@ pub struct RawJson {
 }
 
 pub fn raw_schema() -> Schema {
-    Schema::new(vec![Field::new("value", DataType::Utf8, false)])
+    Schema::new(vec![ArroyoExtensionType::add_metadata(
+        Some(ArroyoExtensionType::JSON),
+        Field::new("value", DataType::Utf8, false),
+    )])
 }
 
 pub static MESSAGES_RECV: &str = "arroyo_worker_messages_recv";