diff --git a/src/lib.rs b/src/lib.rs
index 7e649a10..2cf85ff0 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -10,6 +10,7 @@ extern crate serde;
 #[macro_use]
 extern crate serde_derive;
 extern crate serde_json;
+#[macro_use]
 extern crate serde_plain;
 extern crate url;
 extern crate url_serde;
diff --git a/src/protocol/v7.rs b/src/protocol/v7.rs
index 79a5eb4d..1eb655a8 100644
--- a/src/protocol/v7.rs
+++ b/src/protocol/v7.rs
@@ -146,6 +146,7 @@ pub struct Stacktrace {
 
 /// Represents a thread id.
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq, Ord, PartialOrd, Hash)]
+#[serde(untagged)]
 pub enum ThreadId {
     /// Integer representation for the thread id
     Int(i64),
@@ -168,6 +169,16 @@ impl fmt::Display for ThreadId {
     }
 }
 
+/// Represents an address.
+#[derive(Default, Debug, Clone, PartialEq, Eq, Ord, PartialOrd, Hash)]
+pub struct Addr(pub u64);
+
+impl fmt::Display for Addr {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "0x{:x}", self.0)
+    }
+}
+
 /// Represents a single thread.
 #[derive(Serialize, Deserialize, Debug, Default, Clone, PartialEq)]
 #[serde(default)]
@@ -908,3 +919,37 @@ impl Serialize for DebugImage {
         c.serialize(serializer)
     }
 }
+
+impl<'de> Deserialize<'de> for Addr {
+    fn deserialize<D>(deserializer: D) -> Result<Addr, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        #[derive(Deserialize)]
+        #[serde(untagged)]
+        enum Repr {
+            Str(String),
+            Uint(u64),
+        }
+
+        Ok(Addr(match Repr::deserialize(deserializer).map_err(D::Error::custom)? {
+            Repr::Str(s) => {
+                if s.len() > 2 && (&s[..2] == "0x" || &s[..2] == "0X") {
+                    u64::from_str_radix(&s[2..], 16).map_err(D::Error::custom)?
+                } else {
+                    u64::from_str_radix(&s, 10).map_err(D::Error::custom)?
+                }
+            }
+            Repr::Uint(val) => val
+        }))
+    }
+}
+
+impl Serialize for Addr {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        serializer.serialize_str(&format!("0x{:0x}", self.0))
+    }
+}
diff --git a/tests/test_protocol_v7.rs b/tests/test_protocol_v7.rs
index 80c6796e..0b129018 100644
--- a/tests/test_protocol_v7.rs
+++ b/tests/test_protocol_v7.rs
@@ -485,3 +485,25 @@ fn test_full_exception_stacktrace() {
          \"symbol_addr\":0}],\"frames_omitted\":[1,2]}}]}}"
     );
 }
+
+#[test]
+fn test_addr_format() {
+    assert_eq!(serde_json::to_string(&v7::Addr(0)).unwrap(), "\"0x0\"");
+    assert_eq!(serde_json::to_string(&v7::Addr(42)).unwrap(), "\"0x2a\"");
+    assert_eq!(serde_json::from_str::<v7::Addr>("0").unwrap(), v7::Addr(0));
+    assert_eq!(serde_json::from_str::<v7::Addr>("\"0\"").unwrap(), v7::Addr(0));
+    assert_eq!(serde_json::from_str::<v7::Addr>("\"0x0\"").unwrap(), v7::Addr(0));
+    assert_eq!(serde_json::from_str::<v7::Addr>("42").unwrap(), v7::Addr(42));
+    assert_eq!(serde_json::from_str::<v7::Addr>("\"42\"").unwrap(), v7::Addr(42));
+    assert_eq!(serde_json::from_str::<v7::Addr>("\"0x2a\"").unwrap(), v7::Addr(42));
+    assert_eq!(serde_json::from_str::<v7::Addr>("\"0X2A\"").unwrap(), v7::Addr(42));
+}
+
+#[test]
+fn test_thread_id_format() {
+    assert_eq!(serde_json::to_string(&v7::ThreadId::Int(0)).unwrap(), "0");
+    assert_eq!(serde_json::to_string(&v7::ThreadId::Int(42)).unwrap(), "42");
+    assert_eq!(serde_json::to_string(&v7::ThreadId::String("x".into())).unwrap(), "\"x\"");
+    assert_eq!(serde_json::from_str::<v7::ThreadId>("0").unwrap(), v7::ThreadId::Int(0));
+    assert_eq!(serde_json::from_str::<v7::ThreadId>("\"0\"").unwrap(), v7::ThreadId::String("0".into()));
+}