diff --git a/bytestring-strict-builder.cabal b/bytestring-strict-builder.cabal
--- a/bytestring-strict-builder.cabal
+++ b/bytestring-strict-builder.cabal
@@ -1,7 +1,7 @@
 name:
   bytestring-strict-builder
 version:
-  0.4.5
+  0.4.5.1
 category:
   Text, ByteString, Builders, Serialization
 synopsis:
@@ -74,11 +74,11 @@
   build-depends:
     bytestring-strict-builder,
     -- testing:
-    tasty == 0.11.*,
-    tasty-quickcheck == 0.8.*,
-    tasty-smallcheck == 0.8.*,
-    tasty-hunit == 0.9.*,
+    tasty >= 0.12 && < 2,
+    tasty-quickcheck >= 0.9 && < 0.11,
+    tasty-hunit >= 0.9 && < 0.11,
     quickcheck-instances >= 0.3.11 && < 0.4,
+    QuickCheck >= 2.8.1 && < 3,
     -- general:
     rerebase == 1.*
 
@@ -100,5 +100,5 @@
     Haskell2010
   build-depends:
     bytestring-strict-builder,
-    criterion == 1.1.*,
+    criterion >= 1.1 && < 1.5,
     rerebase == 1.*
diff --git a/library/ByteString/StrictBuilder.hs b/library/ByteString/StrictBuilder.hs
--- a/library/ByteString/StrictBuilder.hs
+++ b/library/ByteString/StrictBuilder.hs
@@ -50,7 +50,8 @@
       population =
         foldMap (\(Builder _ x) -> x) builders
 
-instance Semigroup Builder
+instance Semigroup Builder where
+  (<>) = mappend
 
 instance IsString Builder where
   fromString =
diff --git a/library/ByteString/StrictBuilder/Population.hs b/library/ByteString/StrictBuilder/Population.hs
--- a/library/ByteString/StrictBuilder/Population.hs
+++ b/library/ByteString/StrictBuilder/Population.hs
@@ -20,7 +20,8 @@
   mappend (Population leftPtrUpdate) (Population rightPtrUpdate) =
     Population (leftPtrUpdate >=> rightPtrUpdate)
 
-instance Semigroup Population
+instance Semigroup Population where
+  (<>) = mappend
 
 
 {-|