diff --git a/source/vibe/core/concurrency.d b/source/vibe/core/concurrency.d
index 70be177..f6402c5 100644
--- a/source/vibe/core/concurrency.d
+++ b/source/vibe/core/concurrency.d
@@ -769,7 +769,7 @@ private mixin template isolatedArrayMethods(T, bool mutableRef = true)
 		@property void length(size_t value) pure { m_array.length = value; }
 
 
-		void opCatAssign(T item) pure
+		void opOpAssign(string op = "~")(T item) pure
 		{
 			static if( isCopyable!T ) m_array ~= item;
 			else {
@@ -778,7 +778,7 @@ private mixin template isolatedArrayMethods(T, bool mutableRef = true)
 			}
 		}
 
-		void opCatAssign(IsolatedArray!T array) pure
+		void opOpAssign(string op = "~")(IsolatedArray!T array) pure
 		{
 			static if( isCopyable!T ) m_array ~= array.m_array;
 			else {
diff --git a/source/vibe/core/core.d b/source/vibe/core/core.d
index ee507a2..543ed2b 100644
--- a/source/vibe/core/core.d
+++ b/source/vibe/core/core.d
@@ -1145,7 +1145,7 @@ struct Timer {
 	/** Resets the timer to the specified timeout
 	*/
 	void rearm(Duration dur, bool periodic = false) nothrow
-		in { assert(dur > 0.seconds, "Negative timer duration specified."); }
+		in { assert(dur >= 0.seconds, "Negative timer duration specified."); }
 		body { m_driver.timers.set(m_id, dur, periodic ? dur : 0.seconds); }
 
 	/** Resets the timer and avoids any firing.
diff --git a/source/vibe/core/stream.d b/source/vibe/core/stream.d
index 6a68f87..ab34f6a 100644
--- a/source/vibe/core/stream.d
+++ b/source/vibe/core/stream.d
@@ -27,12 +27,12 @@ public import eventcore.driver : IOMode;
 
 /** Pipes an InputStream directly into this OutputStream.
 
-	The number of bytes written is either the whole input stream when `nbytes == 0`, or exactly
-	`nbytes` for `nbytes > 0`. If the input stream contains less than `nbytes` of data, an
-	exception is thrown.
+	The number of bytes written is either the whole input stream when
+	`nbytes == ulong.max`, or exactly `nbytes` for `nbytes < ulong.max`. If the
+	input stream contains less than `nbytes` of data, an exception is thrown.
 
 	Returns:
-		The actual number of bytes written is returned. If `nbytes` is  given
+		The actual number of bytes written is returned. If `nbytes` is given
 		and not equal to `ulong.max`, íts value will be returned.
 */
 ulong pipe(InputStream, OutputStream)(InputStream source, OutputStream sink, ulong nbytes)