diff --git a/Cargo.toml b/Cargo.toml
index 4c6ca8575..74905488f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -55,7 +55,6 @@ debug = false
 lto = true
 debug-assertions = false
 
-
 [features]
 default = ["mmap"]
 streamdict = []
diff --git a/src/indexer/index_writer.rs b/src/indexer/index_writer.rs
index 17e66f4c4..e882facf1 100644
--- a/src/indexer/index_writer.rs
+++ b/src/indexer/index_writer.rs
@@ -81,10 +81,6 @@ pub struct IndexWriter {
     committed_opstamp: u64,
 }
 
-// IndexWriter cannot be sent to another thread.
-impl !Send for IndexWriter {}
-impl !Sync for IndexWriter {}
-
 /// Open a new index writer. Attempts to acquire a lockfile.
 ///
 /// The lockfile should be deleted on drop, but it is possible
diff --git a/src/indexer/stamper.rs b/src/indexer/stamper.rs
index 63b91f4a4..f9eee3136 100644
--- a/src/indexer/stamper.rs
+++ b/src/indexer/stamper.rs
@@ -1,15 +1,70 @@
-use std::sync::atomic::{AtomicU64, Ordering};
-use std::sync::Arc;
+// AtomicU64 have not landed in stable.
+// For the moment let's just use AtomicUsize on
+// x86/64 bit platform, and a mutex on other platform.
 
-#[derive(Clone, Default)]
-pub struct Stamper(Arc<AtomicU64>);
+#[cfg(target="x86_64")]
+mod archicture_impl {
 
-impl Stamper {
-    pub fn new(first_opstamp: u64) -> Stamper {
-        Stamper(Arc::new(AtomicU64::new(first_opstamp)))
-    }
+    use std::sync::Arc;
+    use std::sync::atomic::{AtomicUsize, Ordering};
 
-    pub fn stamp(&self) -> u64 {
-        self.0.fetch_add(1u64, Ordering::SeqCst)
+    #[derive(Clone, Default)]
+    pub struct Stamper(Arc<AtomicU64>);
+
+    impl Stamper {
+        pub fn new(first_opstamp: u64) -> Stamper {
+            Stamper(Arc::new(AtomicU64::new(first_opstamp)))
+        }
+
+        pub fn stamp(&self) -> u64 {
+            self.0.fetch_add(1u64, Ordering::SeqCst) as u64
+        }
     }
 }
+
+
+
+
+#[cfg(not(target="x86_64"))]
+mod archicture_impl {
+
+    use std::sync::{Arc, Mutex};
+
+    #[derive(Clone, Default)]
+    pub struct Stamper(Arc<Mutex<u64>>);
+
+    impl Stamper {
+        pub fn new(first_opstamp: u64) -> Stamper {
+            Stamper(Arc::new(Mutex::new(first_opstamp)))
+        }
+
+        pub fn stamp(&self) -> u64 {
+            let mut guard = self.0.lock().expect("Failed to lock the stamper");
+            let previous_val = *guard;
+            *guard = previous_val + 1;
+            previous_val
+        }
+    }
+}
+
+pub use self::archicture_impl::Stamper;
+
+
+#[cfg(test)]
+mod test {
+
+    use super::Stamper;
+
+    #[test]
+    fn test_stamper() {
+        let stamper = Stamper::new(7u64);
+        assert_eq!(stamper.stamp(), 7u64);
+        assert_eq!(stamper.stamp(), 8u64);
+
+        let stamper_clone = stamper.clone();
+        assert_eq!(stamper.stamp(), 9u64);
+
+        assert_eq!(stamper.stamp(), 10u64);
+        assert_eq!(stamper_clone.stamp(), 11u64);
+    }
+}
\ No newline at end of file
diff --git a/src/lib.rs b/src/lib.rs
index 4a39cdd4f..eec646886 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -2,9 +2,8 @@
 #![cfg_attr(feature = "cargo-clippy", allow(module_inception))]
 #![cfg_attr(feature = "cargo-clippy", allow(inline_always))]
 
-#![feature(optin_builtin_traits)]
 #![feature(collections_range)]
-#![feature(integer_atomics)]
+
 #![feature(drain_filter)]
 #![cfg_attr(test, feature(test))]
 #![cfg_attr(test, feature(iterator_step_by))]