diff --git a/CHANGELOG.md b/CHANGELOG.md
index fb3cdbfd1fea..dcbfecab7da4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -56,6 +56,14 @@ Now, there are two options to set up the SDK:
    );
    ```
 
+## 9.0.0-alpha.0
+
+This is an alpha release of the upcoming major release of version 9.
+This release does not yet entail a comprehensive changelog as version 9 is not yet stable.
+
+For this release's iteration of the migration guide, see the [Migration Guide as per `9.0.0-alpha.0`](https://github.com/getsentry/sentry-javascript/blob/6e4b593adcc4ce951afa8ae0cda0605ecd226cda/docs/migration/v8-to-v9.md).
+Please note that the migration guide is work in progress and subject to change.
+
 ## 8.45.0
 
 - feat(core): Add `handled` option to `captureConsoleIntegration` ([#14664](https://github.com/getsentry/sentry-javascript/pull/14664))
diff --git a/dev-packages/browser-integration-tests/package.json b/dev-packages/browser-integration-tests/package.json
index 58e378a0c582..bfd1ed3d2717 100644
--- a/dev-packages/browser-integration-tests/package.json
+++ b/dev-packages/browser-integration-tests/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/browser-integration-tests",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "main": "index.js",
   "license": "MIT",
   "engines": {
@@ -43,7 +43,7 @@
     "@babel/preset-typescript": "^7.16.7",
     "@playwright/test": "^1.44.1",
     "@sentry-internal/rrweb": "2.31.0",
-    "@sentry/browser": "8.45.0",
+    "@sentry/browser": "9.0.0-alpha.0",
     "axios": "1.7.7",
     "babel-loader": "^8.2.2",
     "fflate": "0.8.2",
diff --git a/dev-packages/bundle-analyzer-scenarios/package.json b/dev-packages/bundle-analyzer-scenarios/package.json
index c5146697c4d4..fc9c659d8509 100644
--- a/dev-packages/bundle-analyzer-scenarios/package.json
+++ b/dev-packages/bundle-analyzer-scenarios/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/bundle-analyzer-scenarios",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Scenarios to test bundle analysis with",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/dev-packages/bundle-analyzer-scenarios",
diff --git a/dev-packages/clear-cache-gh-action/package.json b/dev-packages/clear-cache-gh-action/package.json
index acf92547dca5..47764f3756c6 100644
--- a/dev-packages/clear-cache-gh-action/package.json
+++ b/dev-packages/clear-cache-gh-action/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@sentry-internal/clear-cache-gh-action",
   "description": "An internal Github Action to clear GitHub caches.",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "license": "MIT",
   "engines": {
     "node": ">=18"
diff --git a/dev-packages/e2e-tests/package.json b/dev-packages/e2e-tests/package.json
index 958b1645e1c0..669be320b4a1 100644
--- a/dev-packages/e2e-tests/package.json
+++ b/dev-packages/e2e-tests/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/e2e-tests",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "license": "MIT",
   "private": true,
   "scripts": {
diff --git a/dev-packages/e2e-tests/test-applications/astro-5/package.json b/dev-packages/e2e-tests/test-applications/astro-5/package.json
index 41724788f169..170c716be756 100644
--- a/dev-packages/e2e-tests/test-applications/astro-5/package.json
+++ b/dev-packages/e2e-tests/test-applications/astro-5/package.json
@@ -15,7 +15,7 @@
     "@astrojs/node": "^9.0.0",
     "@playwright/test": "^1.46.0",
     "@sentry-internal/test-utils": "link:../../../test-utils",
-    "@sentry/astro": "^8.42.0",
+    "@sentry/astro": "latest || *",
     "astro": "^5.0.3"
   },
   "pnpm": {
diff --git a/dev-packages/external-contributor-gh-action/package.json b/dev-packages/external-contributor-gh-action/package.json
index a4857bd41082..aa3aeec3d29f 100644
--- a/dev-packages/external-contributor-gh-action/package.json
+++ b/dev-packages/external-contributor-gh-action/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@sentry-internal/external-contributor-gh-action",
   "description": "An internal Github Action to add external contributors to the CHANGELOG.md file.",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "license": "MIT",
   "engines": {
     "node": ">=18"
diff --git a/dev-packages/node-integration-tests/package.json b/dev-packages/node-integration-tests/package.json
index 6680405b3ac1..571397d12c8c 100644
--- a/dev-packages/node-integration-tests/package.json
+++ b/dev-packages/node-integration-tests/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/node-integration-tests",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "license": "MIT",
   "engines": {
     "node": ">=18"
@@ -31,9 +31,9 @@
     "@nestjs/core": "10.4.6",
     "@nestjs/platform-express": "10.4.6",
     "@prisma/client": "6.2.1",
-    "@sentry/aws-serverless": "8.45.0",
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0",
+    "@sentry/aws-serverless": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0",
     "@types/mongodb": "^3.6.20",
     "@types/mysql": "^2.15.21",
     "@types/pg": "^8.6.5",
diff --git a/dev-packages/rollup-utils/package.json b/dev-packages/rollup-utils/package.json
index 763f043da327..30c4e5c8fc34 100644
--- a/dev-packages/rollup-utils/package.json
+++ b/dev-packages/rollup-utils/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/rollup-utils",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Rollup utilities used at Sentry for the Sentry JavaScript SDK",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/rollup-utils",
diff --git a/dev-packages/size-limit-gh-action/package.json b/dev-packages/size-limit-gh-action/package.json
index c40c18645d6a..9021bc543c5d 100644
--- a/dev-packages/size-limit-gh-action/package.json
+++ b/dev-packages/size-limit-gh-action/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@sentry-internal/size-limit-gh-action",
   "description": "An internal Github Action to compare the current size of a PR against the one on develop.",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "license": "MIT",
   "engines": {
     "node": ">=18"
diff --git a/dev-packages/test-utils/package.json b/dev-packages/test-utils/package.json
index 8e8afec9f698..5758b5229e80 100644
--- a/dev-packages/test-utils/package.json
+++ b/dev-packages/test-utils/package.json
@@ -1,6 +1,6 @@
 {
   "private": true,
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "name": "@sentry-internal/test-utils",
   "author": "Sentry",
   "license": "MIT",
@@ -45,7 +45,7 @@
   },
   "devDependencies": {
     "@playwright/test": "^1.44.1",
-    "@sentry/core": "8.45.0"
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "volta": {
     "extends": "../../package.json"
diff --git a/lerna.json b/lerna.json
index febf4090d555..aeec6a76eb9b 100644
--- a/lerna.json
+++ b/lerna.json
@@ -1,5 +1,5 @@
 {
   "$schema": "node_modules/lerna/schemas/lerna-schema.json",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "npmClient": "yarn"
 }
diff --git a/packages/angular/package.json b/packages/angular/package.json
index 1ec948299d01..80626cc5cdbe 100644
--- a/packages/angular/package.json
+++ b/packages/angular/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/angular",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Angular",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/angular",
@@ -21,8 +21,8 @@
     "rxjs": "^6.5.5 || ^7.x"
   },
   "dependencies": {
-    "@sentry/browser": "8.45.0",
-    "@sentry/core": "8.45.0",
+    "@sentry/browser": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0",
     "tslib": "^2.4.1"
   },
   "devDependencies": {
diff --git a/packages/astro/package.json b/packages/astro/package.json
index 1103c6df1093..316907ee1d30 100644
--- a/packages/astro/package.json
+++ b/packages/astro/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/astro",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Astro",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/astro",
@@ -56,9 +56,9 @@
     "astro": ">=3.x || >=4.0.0-beta || >=5.x"
   },
   "dependencies": {
-    "@sentry/browser": "8.45.0",
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0",
+    "@sentry/browser": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0",
     "@sentry/vite-plugin": "^2.22.6"
   },
   "devDependencies": {
diff --git a/packages/aws-serverless/package.json b/packages/aws-serverless/package.json
index ed3900d0d86f..a441069071e1 100644
--- a/packages/aws-serverless/package.json
+++ b/packages/aws-serverless/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/aws-serverless",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for AWS Lambda and AWS Serverless Environments",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/serverless",
@@ -68,8 +68,8 @@
     "@opentelemetry/instrumentation": "^0.57.1",
     "@opentelemetry/instrumentation-aws-lambda": "0.50.2",
     "@opentelemetry/instrumentation-aws-sdk": "0.49.0",
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0",
     "@types/aws-lambda": "^8.10.62"
   },
   "devDependencies": {
diff --git a/packages/browser-utils/package.json b/packages/browser-utils/package.json
index b18c3e3dfa51..b96ebb51962c 100644
--- a/packages/browser-utils/package.json
+++ b/packages/browser-utils/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/browser-utils",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Browser Utilities for all Sentry JavaScript SDKs",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/browser-utils",
@@ -39,7 +39,7 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/core": "8.45.0"
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "scripts": {
     "build": "run-p build:transpile build:types",
diff --git a/packages/browser/package.json b/packages/browser/package.json
index 23563cf5e752..33c3e0e3e350 100644
--- a/packages/browser/package.json
+++ b/packages/browser/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/browser",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for browsers",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/browser",
@@ -39,14 +39,14 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry-internal/browser-utils": "8.45.0",
-    "@sentry-internal/feedback": "8.45.0",
-    "@sentry-internal/replay": "8.45.0",
-    "@sentry-internal/replay-canvas": "8.45.0",
-    "@sentry/core": "8.45.0"
+    "@sentry-internal/browser-utils": "9.0.0-alpha.0",
+    "@sentry-internal/feedback": "9.0.0-alpha.0",
+    "@sentry-internal/replay": "9.0.0-alpha.0",
+    "@sentry-internal/replay-canvas": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "devDependencies": {
-    "@sentry-internal/integration-shims": "8.45.0",
+    "@sentry-internal/integration-shims": "9.0.0-alpha.0",
     "fake-indexeddb": "^4.0.1"
   },
   "scripts": {
diff --git a/packages/bun/package.json b/packages/bun/package.json
index 7f72b54d9894..a3f131277e50 100644
--- a/packages/bun/package.json
+++ b/packages/bun/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/bun",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for bun",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/bun",
@@ -39,9 +39,9 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0",
-    "@sentry/opentelemetry": "8.45.0"
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0",
+    "@sentry/opentelemetry": "9.0.0-alpha.0"
   },
   "devDependencies": {
     "bun-types": "latest"
diff --git a/packages/cloudflare/package.json b/packages/cloudflare/package.json
index 2d114652b6ab..2e32fc07ff1e 100644
--- a/packages/cloudflare/package.json
+++ b/packages/cloudflare/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/cloudflare",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Cloudflare Workers and Pages",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/cloudflare",
@@ -39,7 +39,7 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/core": "8.45.0"
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "optionalDependencies": {
     "@cloudflare/workers-types": "^4.x"
diff --git a/packages/core/package.json b/packages/core/package.json
index 03d947c37bca..06e8d253a628 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/core",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Base implementation for all Sentry JavaScript SDKs",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/core",
diff --git a/packages/deno/package.json b/packages/deno/package.json
index ea9aaaa3c02a..979aac81380a 100644
--- a/packages/deno/package.json
+++ b/packages/deno/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/deno",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Deno",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/deno",
@@ -24,7 +24,7 @@
     "/build"
   ],
   "dependencies": {
-    "@sentry/core": "8.45.0"
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "scripts": {
     "deno-types": "node ./scripts/download-deno-types.mjs",
diff --git a/packages/ember/package.json b/packages/ember/package.json
index c0b03b81be2d..57caba8029e4 100644
--- a/packages/ember/package.json
+++ b/packages/ember/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/ember",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Ember.js",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/ember",
@@ -32,8 +32,8 @@
   "dependencies": {
     "@babel/core": "^7.24.4",
     "@embroider/macros": "^1.16.0",
-    "@sentry/browser": "8.45.0",
-    "@sentry/core": "8.45.0",
+    "@sentry/browser": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0",
     "ember-auto-import": "^2.7.2",
     "ember-cli-babel": "^8.2.0",
     "ember-cli-htmlbars": "^6.1.1",
diff --git a/packages/eslint-config-sdk/package.json b/packages/eslint-config-sdk/package.json
index fc85554ac878..97b01fdbac88 100644
--- a/packages/eslint-config-sdk/package.json
+++ b/packages/eslint-config-sdk/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/eslint-config-sdk",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK eslint config",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/eslint-config-sdk",
@@ -22,8 +22,8 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry-internal/eslint-plugin-sdk": "8.45.0",
-    "@sentry-internal/typescript": "8.45.0",
+    "@sentry-internal/eslint-plugin-sdk": "9.0.0-alpha.0",
+    "@sentry-internal/typescript": "9.0.0-alpha.0",
     "@typescript-eslint/eslint-plugin": "^5.48.0",
     "@typescript-eslint/parser": "^5.48.0",
     "eslint-config-prettier": "^6.11.0",
diff --git a/packages/eslint-plugin-sdk/package.json b/packages/eslint-plugin-sdk/package.json
index 402a304747d5..5fd9990b411c 100644
--- a/packages/eslint-plugin-sdk/package.json
+++ b/packages/eslint-plugin-sdk/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/eslint-plugin-sdk",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK eslint plugin",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/eslint-plugin-sdk",
diff --git a/packages/feedback/package.json b/packages/feedback/package.json
index 3aaa8c2838b8..d2a72405c400 100644
--- a/packages/feedback/package.json
+++ b/packages/feedback/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/feedback",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Sentry SDK integration for user feedback",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/feedback",
@@ -39,7 +39,7 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/core": "8.45.0"
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "devDependencies": {
     "preact": "^10.19.4"
diff --git a/packages/gatsby/package.json b/packages/gatsby/package.json
index 460ee1cc1b51..4231b055c59b 100644
--- a/packages/gatsby/package.json
+++ b/packages/gatsby/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/gatsby",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Gatsby.js",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/gatsby",
@@ -45,8 +45,8 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/core": "8.45.0",
-    "@sentry/react": "8.45.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/react": "9.0.0-alpha.0",
     "@sentry/webpack-plugin": "2.22.7"
   },
   "peerDependencies": {
diff --git a/packages/google-cloud-serverless/package.json b/packages/google-cloud-serverless/package.json
index 8f0fd7cde687..0f24baa37e8b 100644
--- a/packages/google-cloud-serverless/package.json
+++ b/packages/google-cloud-serverless/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/google-cloud-serverless",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Google Cloud Functions",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/google-cloud-serverless",
@@ -48,8 +48,8 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0",
     "@types/express": "^4.17.14"
   },
   "devDependencies": {
diff --git a/packages/integration-shims/package.json b/packages/integration-shims/package.json
index f65568707e25..4f2c8c3af599 100644
--- a/packages/integration-shims/package.json
+++ b/packages/integration-shims/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/integration-shims",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Shims for integrations in Sentry SDK.",
   "main": "build/cjs/index.js",
   "module": "build/esm/index.js",
@@ -55,7 +55,7 @@
     "url": "https://github.com/getsentry/sentry-javascript/issues"
   },
   "dependencies": {
-    "@sentry/core": "8.45.0"
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "engines": {
     "node": ">=18"
diff --git a/packages/nestjs/package.json b/packages/nestjs/package.json
index 234d7df490bd..84e572984005 100644
--- a/packages/nestjs/package.json
+++ b/packages/nestjs/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/nestjs",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for NestJS",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/nestjs",
@@ -47,8 +47,8 @@
     "@opentelemetry/core": "^1.30.1",
     "@opentelemetry/instrumentation": "^0.57.1",
     "@opentelemetry/instrumentation-nestjs-core": "0.44.0",
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0"
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0"
   },
   "devDependencies": {
     "@nestjs/common": "^8.0.0 || ^9.0.0 || ^10.0.0",
diff --git a/packages/nextjs/package.json b/packages/nextjs/package.json
index cc51b50f6fe1..51b57300a532 100644
--- a/packages/nextjs/package.json
+++ b/packages/nextjs/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/nextjs",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Next.js",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/nextjs",
@@ -79,12 +79,12 @@
     "@opentelemetry/api": "^1.9.0",
     "@opentelemetry/semantic-conventions": "^1.28.0",
     "@rollup/plugin-commonjs": "28.0.1",
-    "@sentry-internal/browser-utils": "8.45.0",
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0",
-    "@sentry/opentelemetry": "8.45.0",
-    "@sentry/react": "8.45.0",
-    "@sentry/vercel-edge": "8.45.0",
+    "@sentry-internal/browser-utils": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0",
+    "@sentry/opentelemetry": "9.0.0-alpha.0",
+    "@sentry/react": "9.0.0-alpha.0",
+    "@sentry/vercel-edge": "9.0.0-alpha.0",
     "@sentry/webpack-plugin": "2.22.7",
     "chalk": "3.0.0",
     "resolve": "1.22.8",
diff --git a/packages/node/package.json b/packages/node/package.json
index c745c0f8192b..d7260379a48f 100644
--- a/packages/node/package.json
+++ b/packages/node/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/node",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Sentry Node SDK using OpenTelemetry for performance instrumentation",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/node",
@@ -9,7 +9,9 @@
   "engines": {
     "node": ">=18"
   },
-  "files": ["/build"],
+  "files": [
+    "/build"
+  ],
   "main": "build/cjs/index.js",
   "module": "build/esm/index.js",
   "types": "build/types/index.d.ts",
@@ -54,7 +56,9 @@
   },
   "typesVersions": {
     "<5.0": {
-      "build/types/index.d.ts": ["build/types-ts3.8/index.d.ts"]
+      "build/types/index.d.ts": [
+        "build/types-ts3.8/index.d.ts"
+      ]
     }
   },
   "publishConfig": {
@@ -92,8 +96,8 @@
     "@opentelemetry/sdk-trace-base": "^1.30.1",
     "@opentelemetry/semantic-conventions": "^1.28.0",
     "@prisma/instrumentation": "6.2.1",
-    "@sentry/core": "8.45.0",
-    "@sentry/opentelemetry": "8.45.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/opentelemetry": "9.0.0-alpha.0",
     "import-in-the-middle": "^1.12.0"
   },
   "devDependencies": {
diff --git a/packages/nuxt/package.json b/packages/nuxt/package.json
index bee5e78f7582..eabcb85da71e 100644
--- a/packages/nuxt/package.json
+++ b/packages/nuxt/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/nuxt",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Nuxt (EXPERIMENTAL)",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/nuxt",
@@ -43,13 +43,13 @@
   },
   "dependencies": {
     "@nuxt/kit": "^3.13.2",
-    "@sentry/browser": "8.45.0",
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0",
-    "@sentry/opentelemetry": "8.45.0",
+    "@sentry/browser": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0",
+    "@sentry/opentelemetry": "9.0.0-alpha.0",
     "@sentry/rollup-plugin": "2.22.7",
     "@sentry/vite-plugin": "2.22.6",
-    "@sentry/vue": "8.45.0"
+    "@sentry/vue": "9.0.0-alpha.0"
   },
   "devDependencies": {
     "@nuxt/module-builder": "^0.8.4",
diff --git a/packages/opentelemetry/package.json b/packages/opentelemetry/package.json
index 5436676e1359..06d1034ecc06 100644
--- a/packages/opentelemetry/package.json
+++ b/packages/opentelemetry/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/opentelemetry",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry utilities for OpenTelemetry",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/opentelemetry",
@@ -39,7 +39,7 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/core": "8.45.0"
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "peerDependencies": {
     "@opentelemetry/api": "^1.9.0",
diff --git a/packages/profiling-node/package.json b/packages/profiling-node/package.json
index 0c50ead2bd53..d07295ba2679 100644
--- a/packages/profiling-node/package.json
+++ b/packages/profiling-node/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/profiling-node",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Node.js Profiling",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/profiling-node",
@@ -76,8 +76,8 @@
     "test": "cross-env SENTRY_PROFILER_BINARY_DIR=lib jest --config jest.config.js"
   },
   "dependencies": {
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0",
     "detect-libc": "^2.0.2",
     "node-abi": "^3.61.0"
   },
diff --git a/packages/react/package.json b/packages/react/package.json
index c4ec86d36fc4..43937b525be2 100644
--- a/packages/react/package.json
+++ b/packages/react/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/react",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for React.js",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/react",
@@ -39,8 +39,8 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/browser": "8.45.0",
-    "@sentry/core": "8.45.0",
+    "@sentry/browser": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0",
     "hoist-non-react-statics": "^3.3.2"
   },
   "peerDependencies": {
diff --git a/packages/remix/package.json b/packages/remix/package.json
index afca2a11055a..6c88c8f08797 100644
--- a/packages/remix/package.json
+++ b/packages/remix/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/remix",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Remix",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/remix",
@@ -55,10 +55,10 @@
     "@opentelemetry/api": "^1.9.0",
     "@remix-run/router": "1.x",
     "@sentry/cli": "^2.39.1",
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0",
-    "@sentry/opentelemetry": "8.45.0",
-    "@sentry/react": "8.45.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0",
+    "@sentry/opentelemetry": "9.0.0-alpha.0",
+    "@sentry/react": "9.0.0-alpha.0",
     "glob": "^10.3.4",
     "opentelemetry-instrumentation-remix": "0.8.0",
     "yargs": "^17.6.0"
diff --git a/packages/replay-canvas/package.json b/packages/replay-canvas/package.json
index 8e75f5764e91..c7345547378f 100644
--- a/packages/replay-canvas/package.json
+++ b/packages/replay-canvas/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/replay-canvas",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Replay canvas integration",
   "main": "build/npm/cjs/index.js",
   "module": "build/npm/esm/index.js",
@@ -68,8 +68,8 @@
     "@sentry-internal/rrweb": "2.31.0"
   },
   "dependencies": {
-    "@sentry-internal/replay": "8.45.0",
-    "@sentry/core": "8.45.0"
+    "@sentry-internal/replay": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "engines": {
     "node": ">=18"
diff --git a/packages/replay-internal/package.json b/packages/replay-internal/package.json
index 9c03c07ba691..15307b073666 100644
--- a/packages/replay-internal/package.json
+++ b/packages/replay-internal/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/replay",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "User replays for Sentry",
   "main": "build/npm/cjs/index.js",
   "module": "build/npm/esm/index.js",
@@ -68,7 +68,7 @@
   "homepage": "https://docs.sentry.io/platforms/javascript/session-replay/",
   "devDependencies": {
     "@babel/core": "^7.17.5",
-    "@sentry-internal/replay-worker": "8.45.0",
+    "@sentry-internal/replay-worker": "9.0.0-alpha.0",
     "@sentry-internal/rrweb": "2.31.0",
     "@sentry-internal/rrweb-snapshot": "2.31.0",
     "fflate": "0.8.2",
@@ -76,8 +76,8 @@
     "jsdom-worker": "^0.2.1"
   },
   "dependencies": {
-    "@sentry-internal/browser-utils": "8.45.0",
-    "@sentry/core": "8.45.0"
+    "@sentry-internal/browser-utils": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "engines": {
     "node": ">=18"
diff --git a/packages/replay-worker/package.json b/packages/replay-worker/package.json
index 04e2835b5f51..f161467d64be 100644
--- a/packages/replay-worker/package.json
+++ b/packages/replay-worker/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/replay-worker",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Worker for @sentry-internal/replay",
   "main": "build/esm/index.js",
   "module": "build/esm/index.js",
diff --git a/packages/solid/package.json b/packages/solid/package.json
index 266e1b197b52..dbc847d346cd 100644
--- a/packages/solid/package.json
+++ b/packages/solid/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/solid",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Solid",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/solid",
@@ -44,8 +44,8 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/browser": "8.45.0",
-    "@sentry/core": "8.45.0"
+    "@sentry/browser": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "peerDependencies": {
     "@solidjs/router": "^0.13.4",
diff --git a/packages/solidstart/package.json b/packages/solidstart/package.json
index e64c0d5d4b20..35a060b9e99b 100644
--- a/packages/solidstart/package.json
+++ b/packages/solidstart/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/solidstart",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Solid Start",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/solidstart",
@@ -66,10 +66,10 @@
     }
   },
   "dependencies": {
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0",
-    "@sentry/opentelemetry": "8.45.0",
-    "@sentry/solid": "8.45.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0",
+    "@sentry/opentelemetry": "9.0.0-alpha.0",
+    "@sentry/solid": "9.0.0-alpha.0",
     "@sentry/vite-plugin": "2.22.6"
   },
   "devDependencies": {
diff --git a/packages/svelte/package.json b/packages/svelte/package.json
index f09d41642f2b..b2d492d6c08d 100644
--- a/packages/svelte/package.json
+++ b/packages/svelte/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/svelte",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Svelte",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/svelte",
@@ -39,8 +39,8 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/browser": "8.45.0",
-    "@sentry/core": "8.45.0",
+    "@sentry/browser": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0",
     "magic-string": "^0.30.0"
   },
   "peerDependencies": {
diff --git a/packages/sveltekit/package.json b/packages/sveltekit/package.json
index caf46d50b3d7..077988a47bd1 100644
--- a/packages/sveltekit/package.json
+++ b/packages/sveltekit/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/sveltekit",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for SvelteKit",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/sveltekit",
@@ -40,10 +40,10 @@
     }
   },
   "dependencies": {
-    "@sentry/core": "8.45.0",
-    "@sentry/node": "8.45.0",
-    "@sentry/opentelemetry": "8.45.0",
-    "@sentry/svelte": "8.45.0",
+    "@sentry/core": "9.0.0-alpha.0",
+    "@sentry/node": "9.0.0-alpha.0",
+    "@sentry/opentelemetry": "9.0.0-alpha.0",
+    "@sentry/svelte": "9.0.0-alpha.0",
     "@sentry/vite-plugin": "2.22.6",
     "magic-string": "0.30.7",
     "magicast": "0.2.8",
diff --git a/packages/types/package.json b/packages/types/package.json
index 5f62f34c4f98..edfa3f034810 100644
--- a/packages/types/package.json
+++ b/packages/types/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/types",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Types for all Sentry JavaScript SDKs",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/types",
@@ -56,7 +56,7 @@
     "yalc:publish": "yalc publish --push --sig"
   },
   "dependencies": {
-    "@sentry/core": "8.45.0"
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "volta": {
     "extends": "../../package.json"
diff --git a/packages/typescript/package.json b/packages/typescript/package.json
index ed0c5d8bc75e..cc18fd6ab488 100644
--- a/packages/typescript/package.json
+++ b/packages/typescript/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry-internal/typescript",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Typescript configuration used at Sentry",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/typescript",
diff --git a/packages/vercel-edge/package.json b/packages/vercel-edge/package.json
index 1541a445d9bd..7878acf97cce 100644
--- a/packages/vercel-edge/package.json
+++ b/packages/vercel-edge/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/vercel-edge",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for the Vercel Edge Runtime",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/vercel-edge",
@@ -40,7 +40,7 @@
   },
   "dependencies": {
     "@opentelemetry/api": "^1.9.0",
-    "@sentry/core": "8.45.0"
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "devDependencies": {
     "@edge-runtime/types": "3.0.1",
@@ -48,7 +48,7 @@
     "@opentelemetry/resources": "^1.30.1",
     "@opentelemetry/sdk-trace-base": "^1.30.1",
     "@opentelemetry/semantic-conventions": "^1.28.0",
-    "@sentry/opentelemetry": "8.45.0"
+    "@sentry/opentelemetry": "9.0.0-alpha.0"
   },
   "scripts": {
     "build": "run-p build:transpile build:types",
diff --git a/packages/vue/package.json b/packages/vue/package.json
index 1bab4c86066e..5a431738253b 100644
--- a/packages/vue/package.json
+++ b/packages/vue/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/vue",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Official Sentry SDK for Vue.js",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/vue",
@@ -39,8 +39,8 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/browser": "8.45.0",
-    "@sentry/core": "8.45.0"
+    "@sentry/browser": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "peerDependencies": {
     "pinia": "2.x",
diff --git a/packages/wasm/package.json b/packages/wasm/package.json
index 78c19b19c30b..6d863483c1c9 100644
--- a/packages/wasm/package.json
+++ b/packages/wasm/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@sentry/wasm",
-  "version": "8.45.0",
+  "version": "9.0.0-alpha.0",
   "description": "Support for WASM.",
   "repository": "git://github.com/getsentry/sentry-javascript.git",
   "homepage": "https://github.com/getsentry/sentry-javascript/tree/master/packages/wasm",
@@ -39,8 +39,8 @@
     "access": "public"
   },
   "dependencies": {
-    "@sentry/browser": "8.45.0",
-    "@sentry/core": "8.45.0"
+    "@sentry/browser": "9.0.0-alpha.0",
+    "@sentry/core": "9.0.0-alpha.0"
   },
   "scripts": {
     "build": "run-p build:transpile build:bundle build:types",