diff --git a/src/arbitrary.rs b/src/arbitrary.rs
index 86d2e4e..eaa1d94 100644
--- a/src/arbitrary.rs
+++ b/src/arbitrary.rs
@@ -7,7 +7,7 @@ use std::iter;
 
 use ::arbitrary::{size_hint, Arbitrary, Result, Unstructured};
 
-use crate::{HashMap, HashSet, OrdMap, OrdSet, Vector};
+use crate::{hashmap::HashMap, hashset::HashSet, OrdMap, OrdSet, Vector};
 
 fn empty<T: 'static>() -> Box<dyn Iterator<Item = T>> {
     Box::new(iter::empty())
diff --git a/src/hash/map.rs b/src/hash/map.rs
index 02b84ba..6d34f96 100644
--- a/src/hash/map.rs
+++ b/src/hash/map.rs
@@ -57,10 +57,10 @@ use crate::util::{Pool, PoolRef, Ref};
 /// ```
 #[macro_export]
 macro_rules! hashmap {
-    () => { $crate::hashmap::HashMap::new() };
+    () => { $crate::HashMap::new() };
 
     ( $( $key:expr => $value:expr ),* ) => {{
-        let mut map = $crate::hashmap::HashMap::new();
+        let mut map = $crate::HashMap::new();
         $({
             map.insert($key, $value);
         })*;
@@ -68,7 +68,7 @@ macro_rules! hashmap {
     }};
 
     ( $( $key:expr => $value:expr ,)* ) => {{
-        let mut map = $crate::hashmap::HashMap::new();
+        let mut map = $crate::HashMap::new();
         $({
             map.insert($key, $value);
         })*;
@@ -119,7 +119,10 @@ where
     }
 }
 
-impl<K, V> HashMap<K, V, RandomState> {
+impl<K, V, S> HashMap<K, V, S>
+where
+    S: BuildHasher + Default,
+{
     /// Construct an empty hash map.
     #[inline]
     #[must_use]
@@ -141,10 +144,11 @@ impl<K, V> HashMap<K, V, RandomState> {
     }
 }
 
-impl<K, V> HashMap<K, V, RandomState>
+impl<K, V, S> HashMap<K, V, S>
 where
     K: Hash + Eq + Clone,
     V: Clone,
+    S: BuildHasher + Default,
 {
     /// Construct a hash map with a single mapping.
     ///
@@ -152,7 +156,7 @@ where
     ///
     /// ```
     /// # #[macro_use] extern crate im;
-    /// # use im::hashmap::HashMap;
+    /// # use im::HashMap;
     /// let map = HashMap::unit(123, "onetwothree");
     /// assert_eq!(
     ///   map.get(&123),
@@ -161,8 +165,8 @@ where
     /// ```
     #[inline]
     #[must_use]
-    pub fn unit(k: K, v: V) -> HashMap<K, V> {
-        HashMap::new().update(k, v)
+    pub fn unit(k: K, v: V) -> HashMap<K, V, S> {
+        HashMap::default().update(k, v)
     }
 }
 
@@ -175,7 +179,7 @@ impl<K, V, S> HashMap<K, V, S> {
     ///
     /// ```
     /// # #[macro_use] extern crate im;
-    /// # use im::hashmap::HashMap;
+    /// # use im::HashMap;
     /// assert!(
     ///   !hashmap!{1 => 2}.is_empty()
     /// );
@@ -2219,7 +2223,7 @@ mod test {
 
     #[test]
     fn large_map() {
-        let mut map = HashMap::new();
+        let mut map = crate::HashMap::new();
         let size = 32769;
         for i in 0..size {
             map.insert(i, i);
diff --git a/src/hash/set.rs b/src/hash/set.rs
index 4f1dfee..8435416 100644
--- a/src/hash/set.rs
+++ b/src/hash/set.rs
@@ -33,8 +33,8 @@ use std::ops::{Add, Deref, Mul};
 
 use crate::nodes::hamt::{hash_key, Drain as NodeDrain, HashValue, Iter as NodeIter, Node};
 use crate::ordset::OrdSet;
-use crate::Vector;
 use crate::util::{Pool, PoolRef, Ref};
+use crate::Vector;
 
 /// Construct a set from a sequence of values.
 ///
@@ -52,10 +52,10 @@ use crate::util::{Pool, PoolRef, Ref};
 /// ```
 #[macro_export]
 macro_rules! hashset {
-    () => { $crate::hashset::HashSet::new() };
+    () => { $crate::HashSet::new() };
 
     ( $($x:expr),* ) => {{
-        let mut l = $crate::hashset::HashSet::new();
+        let mut l = $crate::HashSet::new();
         $(
             l.insert($x);
         )*
@@ -63,7 +63,7 @@ macro_rules! hashset {
     }};
 
     ( $($x:expr ,)* ) => {{
-        let mut l = $crate::hashset::HashSet::new();
+        let mut l = $crate::HashSet::new();
         $(
             l.insert($x);
         )*
@@ -125,7 +125,10 @@ where
     }
 }
 
-impl<A> HashSet<A, RandomState> {
+impl<A, S> HashSet<A, S>
+where
+    S: BuildHasher + Default,
+{
     /// Construct an empty set.
     #[must_use]
     pub fn new() -> Self {
@@ -145,9 +148,10 @@ impl<A> HashSet<A, RandomState> {
     }
 }
 
-impl<A> HashSet<A, RandomState>
+impl<A, S> HashSet<A, S>
 where
     A: Hash + Eq + Clone,
+    S: BuildHasher + Default,
 {
     /// Construct a set with a single value.
     ///
@@ -155,7 +159,7 @@ where
     ///
     /// ```
     /// # #[macro_use] extern crate im;
-    /// # use im::hashset::HashSet;
+    /// # use im::HashSet;
     /// # use std::sync::Arc;
     /// let set = HashSet::unit(123);
     /// assert!(set.contains(&123));
diff --git a/src/lib.rs b/src/lib.rs
index 0444dbd..5bf9a3d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -390,8 +390,10 @@ compile_error!(
     "The `pool` feature is not threadsafe but you've enabled it on a threadsafe version of `im`."
 );
 
-pub use crate::hashmap::HashMap;
-pub use crate::hashset::HashSet;
+/// HashMap with random state hasher
+pub type HashMap<K, V> = crate::hashmap::HashMap<K, V, std::collections::hash_map::RandomState>;
+/// HashSet with random state hasher
+pub type HashSet<A> = crate::hashset::HashSet<A, std::collections::hash_map::RandomState>;
 pub use crate::ordmap::OrdMap;
 pub use crate::ordset::OrdSet;
 #[doc(inline)]
diff --git a/src/quickcheck.rs b/src/quickcheck.rs
index 9005815..4264f78 100644
--- a/src/quickcheck.rs
+++ b/src/quickcheck.rs
@@ -1,4 +1,4 @@
-use crate::{HashMap, HashSet, OrdMap, OrdSet, Vector};
+use crate::{hashmap::HashMap, hashset::HashSet, OrdMap, OrdSet, Vector};
 use ::quickcheck::{Arbitrary, Gen};
 use std::hash::{BuildHasher, Hash};
 use std::iter::FromIterator;