diff --git a/Changelog.md b/Changelog.md
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,3 +1,7 @@
+## 1.2.6
+
+* Increased upper-bounds of aeson to < 0.10 and of attoparsec to < 0.14.
+
 ## 1.2.5
 
 * Increased the upper-bound of base to allow < 4.9. Now builds on
diff --git a/engine-io.cabal b/engine-io.cabal
--- a/engine-io.cabal
+++ b/engine-io.cabal
@@ -1,5 +1,5 @@
 name: engine-io
-version: 1.2.5
+version: 1.2.6
 synopsis: A Haskell implementation of Engine.IO
 homepage: http://github.com/ocharles/engine.io
 license: BSD3
@@ -27,9 +27,9 @@
    RankNTypes, OverloadedStrings, RecordWildCards
 
   build-depends:
-    aeson >=0.7 && <0.9,
+    aeson >=0.7 && <0.10,
     async >=2.0 && <2.1,
-    attoparsec >=0.11 && <0.13,
+    attoparsec >=0.11 && <0.14,
     base >=4.6 && <4.9,
     base64-bytestring >=1.0 && <1.1,
     bytestring >=0.10.2.0 && <0.11,