diff --git a/CHANGELOG.md b/CHANGELOG.md
index ef6a87ebb9..51e3c419e3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,41 @@
 
 All notable changes to this project will be documented in this file.
 
+## [4.3.4] - 2025-02-27
+
+### Security
+
+- Update dependencies
+- Change HTML sanitization to remove unusable and unused `embed` tag (#34021 by @ClearlyClaire, [GHSA-mq2m-hr29-8gqf](https://github.com/mastodon/mastodon/security/advisories/GHSA-mq2m-hr29-8gqf))
+- Fix rate-limit on sign-up email verification ([GHSA-v39f-c9jj-8w7h](https://github.com/mastodon/mastodon/security/advisories/GHSA-v39f-c9jj-8w7h))
+- Fix improper disclosure of domain blocks to unverified users ([GHSA-94h4-fj37-c825](https://github.com/mastodon/mastodon/security/advisories/GHSA-94h4-fj37-c825))
+
+### Changed
+
+- Change preview cards to be shown when Content Warnings are expanded (#33827 by @ClearlyClaire)
+- Change warnings against changing encryption secrets to be even more noticeable (#33631 by @ClearlyClaire)
+- Change `mastodon:setup` to prevent overwriting already-configured servers (#33603, #33616, and #33684 by @ClearlyClaire and @mjankowski)
+- Change notifications from moderators to not be filtered (#32974 and #33654 by @ClearlyClaire and @mjankowski)
+
+### Fixed
+
+- Fix `GET /api/v2/notifications/:id` and `POST /api/v2/notifications/:id/dismiss` for ungrouped notifications (#33990 by @ClearlyClaire)
+- Fix issue with some versions of libvips on some systems (#33853 by @kleisauke)
+- Fix handling of duplicate mentions in incoming status `Update` (#33911 by @ClearlyClaire)
+- Fix inefficiencies in timeline generation (#33839 and #33842 by @ClearlyClaire)
+- Fix emoji rewrite adding unnecessary curft to the DOM for most emoji (#33818 by @ClearlyClaire)
+- Fix `tootctl feeds build` not building list timelines (#33783 by @ClearlyClaire)
+- Fix flaky test in `/api/v2/notifications` tests (#33773 by @ClearlyClaire)
+- Fix incorrect signature after HTTP redirect (#33757 and #33769 by @ClearlyClaire)
+- Fix polls not being validated on edition (#33755 by @ClearlyClaire)
+- Fix media preview height in compose form when 3 or more images are attached (#33571 by @ClearlyClaire)
+- Fix preview card sizing in “Author attribution” in profile settings (#33482 by @ClearlyClaire)
+- Fix processing of incoming notifications for unfilterable types (#33429 by @ClearlyClaire)
+- Fix featured tags for remote accounts not being kept up to date (#33372, #33406, and #33425 by @ClearlyClaire and @mjankowski)
+- Fix notification polling showing a loading bar in web UI (#32960 by @Gargron)
+- Fix accounts table long display name (#29316 by @WebCoder49)
+- Fix exclusive lists interfering with notifications (#28162 by @ShadowJonathan)
+
 ## [4.3.3] - 2025-01-16
 
 ### Security
diff --git a/docker-compose.yml b/docker-compose.yml
index 93e5bd4ecd..c0ac6707fc 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -59,7 +59,7 @@ services:
   web:
     # You can uncomment the following line if you want to not use the prebuilt image, for example if you have local code changes
     # build: .
-    image: ghcr.io/mastodon/mastodon:v4.3.3
+    image: ghcr.io/mastodon/mastodon:v4.3.4
     restart: always
     env_file: .env.production
     command: bundle exec puma -C config/puma.rb
@@ -83,7 +83,7 @@ services:
     # build:
     #   dockerfile: ./streaming/Dockerfile
     #   context: .
-    image: ghcr.io/mastodon/mastodon-streaming:v4.3.3
+    image: ghcr.io/mastodon/mastodon-streaming:v4.3.4
     restart: always
     env_file: .env.production
     command: node ./streaming/index.js
@@ -102,7 +102,7 @@ services:
   sidekiq:
     # You can uncomment the following line if you want to not use the prebuilt image, for example if you have local code changes
     # build: .
-    image: ghcr.io/mastodon/mastodon:v4.3.3
+    image: ghcr.io/mastodon/mastodon:v4.3.4
     restart: always
     env_file: .env.production
     command: bundle exec sidekiq
diff --git a/lib/mastodon/version.rb b/lib/mastodon/version.rb
index ad8fb0a345..1e7e5a0f5c 100644
--- a/lib/mastodon/version.rb
+++ b/lib/mastodon/version.rb
@@ -17,7 +17,7 @@ module Mastodon
     end
 
     def default_prerelease
-      'alpha.2'
+      'alpha.3'
     end
 
     def prerelease