diff --git a/packages/core/src/envelope.ts b/packages/core/src/envelope.ts
index 023955df2208..f4e8b18f1bd4 100644
--- a/packages/core/src/envelope.ts
+++ b/packages/core/src/envelope.ts
@@ -35,6 +35,8 @@ function enhanceEventWithSdkInfo(event: Event, sdkInfo?: SdkInfo): Event {
   event.sdk.version = event.sdk.version || sdkInfo.version;
   event.sdk.integrations = [...(event.sdk.integrations || []), ...(sdkInfo.integrations || [])];
   event.sdk.packages = [...(event.sdk.packages || []), ...(sdkInfo.packages || [])];
+  // Either 'CDN', 'npm', or 'lambdaLayer'. This is hardcoded as part of our build process.
+  event.sdk.source = '__SDK_SOURCE__';
   return event;
 }
 
diff --git a/packages/serverless/rollup.aws.config.js b/packages/serverless/rollup.aws.config.js
index 23c10b757f33..6da2c2ef4c7c 100644
--- a/packages/serverless/rollup.aws.config.js
+++ b/packages/serverless/rollup.aws.config.js
@@ -5,7 +5,7 @@ export default [
   ...makeBundleConfigVariants(
     makeBaseBundleConfig({
       // this automatically sets it to be CJS
-      bundleType: 'node',
+      bundleType: 'lambdaLayer',
       entrypoints: ['src/index.awslambda.ts'],
       jsVersion: 'es6',
       licenseTitle: '@sentry/serverless',
diff --git a/packages/types/src/sdkinfo.ts b/packages/types/src/sdkinfo.ts
index 0a839b0c7c95..0c280e521c91 100644
--- a/packages/types/src/sdkinfo.ts
+++ b/packages/types/src/sdkinfo.ts
@@ -5,4 +5,6 @@ export interface SdkInfo {
   version?: string;
   integrations?: string[];
   packages?: Package[];
+  // Either 'CDN', 'npm', or 'lambdaLayer'. This is hardcoded as part of our build process.
+  source?: string;
 }
diff --git a/rollup/bundleHelpers.js b/rollup/bundleHelpers.js
index 41888d54f77e..f1523814be1c 100644
--- a/rollup/bundleHelpers.js
+++ b/rollup/bundleHelpers.js
@@ -10,6 +10,7 @@ import {
   makeBrowserBuildPlugin,
   makeCommonJSPlugin,
   makeIsDebugBuildPlugin,
+  makeSDKSourcePlugin,
   makeLicensePlugin,
   makeNodeResolvePlugin,
   makeCleanupPlugin,
@@ -28,6 +29,8 @@ export function makeBaseBundleConfig(options) {
   const sucrasePlugin = makeSucrasePlugin();
   const cleanupPlugin = makeCleanupPlugin();
   const markAsBrowserBuildPlugin = makeBrowserBuildPlugin(true);
+  const markAsCDNSourcePlugin = makeSDKSourcePlugin('CDN');
+  const markAsLambdaLayerSourcePlugin = makeSDKSourcePlugin('lambdaLayer');
   const licensePlugin = makeLicensePlugin(licenseTitle);
   const tsPlugin = makeTSPlugin(jsVersion.toLowerCase());
 
@@ -43,7 +46,7 @@ export function makeBaseBundleConfig(options) {
       name: 'Sentry',
     },
     context: 'window',
-    plugins: [markAsBrowserBuildPlugin],
+    plugins: [markAsBrowserBuildPlugin, markAsCDNSourcePlugin],
   };
 
   // used by `@sentry/integrations` and `@sentry/wasm` (bundles which need to be combined with a stand-alone SDK bundle)
@@ -76,15 +79,15 @@ export function makeBaseBundleConfig(options) {
       // code to add after the CJS wrapper
       footer: '}(window));',
     },
-    plugins: [markAsBrowserBuildPlugin],
+    plugins: [markAsBrowserBuildPlugin, markAsCDNSourcePlugin],
   };
 
   // used by `@sentry/serverless`, when creating the lambda layer
-  const nodeBundleConfig = {
+  const lambdaLayerBundleConfig = {
     output: {
       format: 'cjs',
     },
-    plugins: [commonJSPlugin],
+    plugins: [commonJSPlugin, markAsLambdaLayerSourcePlugin],
     // Don't bundle any of Node's core modules
     external: builtinModules,
   };
@@ -110,7 +113,7 @@ export function makeBaseBundleConfig(options) {
   const bundleTypeConfigMap = {
     standalone: standAloneBundleConfig,
     addon: addOnBundleConfig,
-    node: nodeBundleConfig,
+    lambdaLayer: lambdaLayerBundleConfig,
   };
 
   return deepMerge.all([sharedBundleConfig, bundleTypeConfigMap[bundleType], packageSpecificConfig || {}], {
diff --git a/rollup/npmHelpers.js b/rollup/npmHelpers.js
index e1657f7ef598..cec45e1b579f 100644
--- a/rollup/npmHelpers.js
+++ b/rollup/npmHelpers.js
@@ -13,6 +13,7 @@ import {
   makeCleanupPlugin,
   makeSucrasePlugin,
   makeDebugBuildStatementReplacePlugin,
+  makeSDKSourcePlugin,
 } from './plugins/index.js';
 import { mergePlugins } from './utils';
 
@@ -31,6 +32,7 @@ export function makeBaseNPMConfig(options = {}) {
   const debugBuildStatementReplacePlugin = makeDebugBuildStatementReplacePlugin();
   const cleanupPlugin = makeCleanupPlugin();
   const extractPolyfillsPlugin = makeExtractPolyfillsPlugin();
+  const markAsNPMSourcePlugin = makeSDKSourcePlugin('npm');
 
   const defaultBaseConfig = {
     input: entrypoints,
@@ -85,6 +87,7 @@ export function makeBaseNPMConfig(options = {}) {
       nodeResolvePlugin,
       sucrasePlugin,
       debugBuildStatementReplacePlugin,
+      markAsNPMSourcePlugin,
       cleanupPlugin,
       extractPolyfillsPlugin,
     ],
diff --git a/rollup/plugins/npmPlugins.js b/rollup/plugins/npmPlugins.js
index ec162615623f..b664cb2a0ffb 100644
--- a/rollup/plugins/npmPlugins.js
+++ b/rollup/plugins/npmPlugins.js
@@ -104,4 +104,21 @@ export function makeDebugBuildStatementReplacePlugin() {
   });
 }
 
+/**
+ * Creates a plugin to replace all instances of "__SDK_SOURCE__" with either "CDN" or "npm".
+ *
+ * @returns A `@rollup/plugin-replace` instance.
+ */
+export function makeSDKSourcePlugin(source) {
+  return replace({
+    // TODO `preventAssignment` will default to true in version 5.x of the replace plugin, at which point we can get rid
+    // of this. (It actually makes no difference in this case whether it's true or false, since we never assign to
+    // `__SDK_SOURCE__`, but if we don't give it a value, it will spam with warnings.)
+    preventAssignment: true,
+    values: {
+      __SDK_SOURCE__: source,
+    },
+  });
+}
+
 export { makeExtractPolyfillsPlugin } from './extractPolyfillsPlugin.js';