diff --git a/FastRng/IRandom.cs b/FastRng/IRandom.cs
index e8f672b..f75699b 100644
--- a/FastRng/IRandom.cs
+++ b/FastRng/IRandom.cs
@@ -1,15 +1,19 @@
+using System;
 using System.Threading;
 using System.Threading.Tasks;
+using FastRng.Distributions;
 
 namespace FastRng
 {
     public interface IRandom
     {
-        public Task<uint> NextNumber(uint rangeStart, uint rangeEnd, CancellationToken cancel = default(CancellationToken));
+        public Task<double> GetUniformDouble(CancellationToken cancel = default);
         
-        public Task<ulong> NextNumber(ulong rangeStart, ulong rangeEnd, CancellationToken cancel = default(CancellationToken));
+        public Task<uint> NextNumber(uint rangeStart, uint rangeEnd, IDistribution distribution, CancellationToken cancel = default);
         
-        public Task<float> NextNumber(float rangeStart, float rangeEnd, CancellationToken cancel = default(CancellationToken));
+        public Task<ulong> NextNumber(ulong rangeStart, ulong rangeEnd, IDistribution distribution, CancellationToken cancel = default);
+        
+        public Task<float> NextNumber(float rangeStart, float rangeEnd, IDistribution distribution, CancellationToken cancel = default);
 
         public void StopProducer();
     }