diff --git a/tripod-id/build.rs b/tripod-id/build.rs
index e596d5e..05f3424 100644
--- a/tripod-id/build.rs
+++ b/tripod-id/build.rs
@@ -1,7 +1,11 @@
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     #[cfg(feature="prost")]
     prost_build::compile_protos(
-        &["proto/tripod_id.proto"],
+        &[
+            "proto/tripod_id/single.proto",
+            "proto/tripod_id/double.proto",
+            "proto/tripod_id/triple.proto"
+        ],
         &["proto/"]
     )?;
     Ok(())
diff --git a/tripod-id/proto/tripod_id.proto b/tripod-id/proto/tripod_id.proto
deleted file mode 100644
index e05c272..0000000
--- a/tripod-id/proto/tripod_id.proto
+++ /dev/null
@@ -1,17 +0,0 @@
-syntax = "proto3";
-package tripod_id;
-
-// Single size tripod id message
-message Single {
-    uint32 id = 1;
-}
-
-// Double size tripod id message
-message Double {
-    uint32 id = 1;
-}
-
-// Triple size tripod id message
-message Triple {
-    uint64 id = 1;
-}
diff --git a/tripod-id/proto/tripod_id/double.proto b/tripod-id/proto/tripod_id/double.proto
new file mode 100644
index 0000000..de43ee6
--- /dev/null
+++ b/tripod-id/proto/tripod_id/double.proto
@@ -0,0 +1,7 @@
+syntax = "proto3";
+package tripod_id;
+
+// Double size tripod id message
+message Double {
+    uint32 id = 1;
+}
diff --git a/tripod-id/proto/tripod_id/single.proto b/tripod-id/proto/tripod_id/single.proto
new file mode 100644
index 0000000..fa1943f
--- /dev/null
+++ b/tripod-id/proto/tripod_id/single.proto
@@ -0,0 +1,7 @@
+syntax = "proto3";
+package tripod_id;
+
+// Single size tripod id message
+message Single {
+    uint32 id = 1;
+}
diff --git a/tripod-id/proto/tripod_id/triple.proto b/tripod-id/proto/tripod_id/triple.proto
new file mode 100644
index 0000000..c26e2cd
--- /dev/null
+++ b/tripod-id/proto/tripod_id/triple.proto
@@ -0,0 +1,7 @@
+syntax = "proto3";
+package tripod_id;
+
+// Triple size tripod id message
+message Triple {
+    uint64 id = 1;
+}
diff --git a/tripod-id/src/prost/double.rs b/tripod-id/src/prost/double.rs
index 8e34f0b..f1e6c44 100644
--- a/tripod-id/src/prost/double.rs
+++ b/tripod-id/src/prost/double.rs
@@ -1,6 +1,6 @@
 use prost::Name;
 
-use crate::{prost::{Double, TripodIdMessage}, Error, TripodId};
+use crate::{prost::{Double, TripodIdMessage}, Error};
 
 impl Name for Double {
     const NAME: &'static str = "Double";
@@ -26,4 +26,28 @@ impl TryFrom<Double> for crate::Double {
             value.id
         )
     }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{Double, DoubleMessage, TripodId};
+
+    #[test]
+    fn nil() {
+        let nil = DoubleMessage{id: 0};
+        assert_eq!(Double::NIL, Double::try_from(nil).unwrap());
+    }
+
+    #[test]
+    fn max() {
+        let max = DoubleMessage{id: u32::from(Double::CAPACITY)-1};
+        assert_eq!(Double::MAX, Double::try_from(max).unwrap());
+    }
+
+    #[test]
+    #[should_panic]
+    fn oversized () {
+        let oversized = DoubleMessage{id: u32::from(Double::CAPACITY)};
+        let _ = Double::try_from(oversized).unwrap();
+    }
 }
\ No newline at end of file
diff --git a/tripod-id/src/prost/mod.rs b/tripod-id/src/prost/mod.rs
index 455b4a3..8774b84 100644
--- a/tripod-id/src/prost/mod.rs
+++ b/tripod-id/src/prost/mod.rs
@@ -1,17 +1,20 @@
-pub mod generated {
-    include!(concat!(env!("OUT_DIR"), "/tripod_id.rs"));
-}
-
 mod single;
 mod double;
 mod triple;
 
-pub use generated::*;
-
 use crate::TripodId;
+
 const PACKAGE_NAME: &'static str = "tripod_id";
+
+include!(concat!(env!("OUT_DIR"), "/tripod_id.rs"));
+
+/// Alias of single tripod-id message
 pub type SingleMessage = Single;
+
+/// Alias of double tripod-id message
 pub type DoubleMessage = Double;
+
+/// Alias of triple tripod-id message
 pub type TripleMessage = Triple;
 
 pub trait TripodIdMessage: From<Self::TripodId> {
diff --git a/tripod-id/src/prost/triple.rs b/tripod-id/src/prost/triple.rs
index 9da6fc6..e4de831 100644
--- a/tripod-id/src/prost/triple.rs
+++ b/tripod-id/src/prost/triple.rs
@@ -1,6 +1,6 @@
 use prost::Name;
 
-use crate::{prost::{Triple, TripodIdMessage}, Error, TripodId};
+use crate::{prost::{Triple, TripodIdMessage}, Error};
 
 impl Name for Triple {
     const NAME: &'static str = "Triple";
@@ -26,4 +26,28 @@ impl TryFrom<Triple> for crate::Triple {
             value.id
         )
     }
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::{Triple, TripleMessage, TripodId};
+
+    #[test]
+    fn nil() {
+        let nil = TripleMessage{id: 0};
+        assert_eq!(Triple::NIL, Triple::try_from(nil).unwrap());
+    }
+
+    #[test]
+    fn max() {
+        let max = TripleMessage{id: u64::from(Triple::CAPACITY)-1};
+        assert_eq!(Triple::MAX, Triple::try_from(max).unwrap());
+    }
+
+    #[test]
+    #[should_panic]
+    fn oversized () {
+        let oversized = TripleMessage{id: u64::from(Triple::CAPACITY)};
+        let _ = Triple::try_from(oversized).unwrap();
+    }
 }
\ No newline at end of file
diff --git a/tripod-id/src/utils.rs b/tripod-id/src/utils.rs
index 99a0800..45fe5e8 100644
--- a/tripod-id/src/utils.rs
+++ b/tripod-id/src/utils.rs
@@ -1,7 +1,3 @@
-use std::str::FromStr;
-
-use crate::Single;
-
 /// Test if the character is valid delimiter.
 pub fn is_delimiter(c: char) -> bool {
     match c {