diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8d535d5..18e1eb0 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,21 @@
 # Changelog
 
+## v0.4.0
+
+This release accomplishes a small redesign of `Stack` and `Context`  that makes the library simpler and more powerful for end users.
+
+- `Discord::Middleware` has been removed
+- `Discord.add_ctx_property` / `Discord.add_ctx_property!` has been removed
+- Middleware can now be *any* class that implements `def call(payload, context, &block)`
+- The middleware chain is advanced by `yield`-ing to the block passed to `call`
+- `Context` is reimplemented as a table of references
+- The client the middleware was registered on can be accessed as `context[Discord::Client]`
+- Each middleware in a chain is made available on `context`, i.e. `context[MyMiddleware]`
+
+Big thanks to @RX14 for the recommendations and code examples that were the foundation of these changes.
+
+See the updated `README.md` and documentation for more details.
+
 ## v0.3.1
 
 Fixes a bug where stacks were registered across event handlers incorrectly, causing events to be distributed wrongly
diff --git a/shard.yml b/shard.yml
index e92e47c..a6ac9d4 100644
--- a/shard.yml
+++ b/shard.yml
@@ -1,5 +1,5 @@
 name: discordcr-middleware
-version: 0.3.1
+version: 0.4.0
 
 authors:
   -  Zac Nowicki <zachnowicki@gmail.com>
diff --git a/src/discordcr-middleware/version.cr b/src/discordcr-middleware/version.cr
index 83142d2..1d6c9a0 100644
--- a/src/discordcr-middleware/version.cr
+++ b/src/discordcr-middleware/version.cr
@@ -1,3 +1,3 @@
 module DiscordMiddleware
-  VERSION = "0.3.1"
+  VERSION = "0.4.0"
 end