diff --git a/CHANGELOG.md b/CHANGELOG.md
index 210287c..d53b524 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,12 @@
 This document contains details of the various releases and their release dates.
 Dates are in the format `yyyy-mm-dd`.
 
+## 3.1 - 2020-01-08
+
+This release fixes a bug in the XML lexer that prevented the parsing of doctypes
+using "public" or "system" instead of "PUBLIC"/"SYSTEM". See issue
+<https://gitlab.com/yorickpeterse/oga/issues/199> for more information.
+
 ## 3.0 - 2019-12-03
 
 This release bumps the Ruby version requirement to Ruby 2.3.0, as we haven't
diff --git a/checksum/oga-3.1-java.gem.sha512 b/checksum/oga-3.1-java.gem.sha512
new file mode 100644
index 0000000..be3a231
--- /dev/null
+++ b/checksum/oga-3.1-java.gem.sha512
@@ -0,0 +1 @@
+a2246547f87d1901e280d9df915bf41a6b78ac14805c5c0f471f5dd1cf617f1e5b3e4aa05e58ae5aa816e188456ccd3638e44a7aba41ed2dfb942f509b2093af
\ No newline at end of file
diff --git a/checksum/oga-3.1.gem.sha512 b/checksum/oga-3.1.gem.sha512
new file mode 100644
index 0000000..48a2bfe
--- /dev/null
+++ b/checksum/oga-3.1.gem.sha512
@@ -0,0 +1 @@
+deb03862d5263b2cb47169267aa37c41be82fcb01d048d840506d2c8924fb0bba6a4407401052e8a5f42d053c2bb3410701316fe21570b35a2981850dc05a481
\ No newline at end of file
diff --git a/lib/oga/version.rb b/lib/oga/version.rb
index 9e38ec0..0a1dd7d 100644
--- a/lib/oga/version.rb
+++ b/lib/oga/version.rb
@@ -1,3 +1,3 @@
 module Oga
-  VERSION = '3.0'
+  VERSION = '3.1'
 end # Oga