diff --git a/Changelog.md b/Changelog.md
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,3 +1,10 @@
+## 1.2.22 -- 2018-09-30
+
+### Other Changes
+
+* Increased the upper-bound of `base` to < 4.13.
+* Increased the upper-bound of `stm` to < 2.6.
+
 ## 1.2.21 -- 2018-08-12
 
 ### Other Changes
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: 1.2.21
+version: 1.2.22
 synopsis: A Haskell implementation of Engine.IO
 homepage: http://github.com/ocharles/engine.io
 license: BSD3
@@ -30,14 +30,14 @@
     aeson >=0.7 && <1.5,
     async >=2.0 && <2.3,
     attoparsec >=0.11 && <0.14,
-    base >=4.6 && <4.12,
+    base >=4.6 && <4.13,
     base64-bytestring >=1.0 && <1.1,
     bytestring >=0.10.2.0 && <0.11,
     errors >= 2.0.0 && <2.4,
     free >= 4.9 && <5.2,
     monad-loops >=0.4 && <0.5,
     mwc-random >=0.13 && <0.15,
-    stm >=2.4 && <2.5,
+    stm >=2.4 && <2.6,
     stm-delay >= 0.1.1 && <0.2,
     text >=0.11 && <1.3,
     transformers >=0.2 && <0.6,