diff --git a/.circleci/config.yml b/.circleci/config.yml
index e14f6b77d..d571a6bac 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -163,7 +163,7 @@ workflows:
             - vault
           filters:
             branches:
-              only: master
+              only: main
           requires:
             - test-built-app-18
             - test-built-app-18-actions-functions
diff --git a/packages/contentful--app-scripts/src/utils.ts b/packages/contentful--app-scripts/src/utils.ts
index efd8c0fe9..68425c2b1 100644
--- a/packages/contentful--app-scripts/src/utils.ts
+++ b/packages/contentful--app-scripts/src/utils.ts
@@ -8,6 +8,17 @@ import { ContentfulFunction, FunctionAppAction } from './types';
 
 const DEFAULT_MANIFEST_PATH = './contentful-app-manifest.json';
 
+const graphQLEvents = {
+  fieldMappingEvent: 'graphql.field.mapping',
+  queryEvent: 'graphql.query',
+};
+
+const appEvents = {
+  appEventFilter: 'appevent.filter',
+  appEventHandler: 'appevent.handler',
+  appEventTransformation: 'appevent.transformation',
+};
+
 export const throwValidationException = (subject: string, message?: string, details?: string) => {
   console.log(`${chalk.red('Validation Error:')} Missing or invalid ${subject}.`);
   message && console.log(message);
@@ -56,10 +67,10 @@ ${err.message}
   throw err;
 };
 
-export const selectFromList = async <T extends (Definition | Organization)>(
+export const selectFromList = async <T extends Definition | Organization>(
   list: T[],
   message: string,
-  cachedOptionEnvVar: string,
+  cachedOptionEnvVar: string
 ): Promise<T> => {
   const cachedEnvVar = process.env[cachedOptionEnvVar];
   const cachedElement = list.find((item) => item.value === cachedEnvVar);
@@ -86,9 +97,13 @@ export const selectFromList = async <T extends (Definition | Organization)>(
   }
 };
 
-type Entities<Type> = Type extends 'actions' ? Omit<FunctionAppAction, 'entryFile'>[] : Omit<ContentfulFunction, 'entryFile'>[];
+type Entities<Type> = Type extends 'actions'
+  ? Omit<FunctionAppAction, 'entryFile'>[]
+  : Omit<ContentfulFunction, 'entryFile'>[];
 
-export function getEntityFromManifest<Type extends 'actions' | 'functions'>(type: Type): Entities<Type> | undefined {
+export function getEntityFromManifest<Type extends 'actions' | 'functions'>(
+  type: Type
+): Entities<Type> | undefined {
   const isManifestExists = fs.existsSync(DEFAULT_MANIFEST_PATH);
 
   if (!isManifestExists) {
@@ -104,30 +119,28 @@ export function getEntityFromManifest<Type extends 'actions' | 'functions'>(type
 
     logProgress(
       `${type === 'actions' ? 'App Actions' : 'functions'} found in ${chalk.bold(
-        DEFAULT_MANIFEST_PATH,
-      )}.`,
+        DEFAULT_MANIFEST_PATH
+      )}.`
     );
 
-    const fieldMappingEvent = "graphql.field.mapping";
-    const queryEvent =  "graphql.query";
-    const appEventFilter = 'appevent.filter';
-
     const items = (manifest[type] as FunctionAppAction[] | ContentfulFunction[]).map((item) => {
       const allowNetworks = Array.isArray(item.allowNetworks)
         ? item.allowNetworks.map(stripProtocol)
         : [];
 
       const accepts = 'accepts' in item && Array.isArray(item.accepts) ? item.accepts : undefined;
-      const hasInvalidEvent = accepts?.some((event) => ![fieldMappingEvent, queryEvent, appEventFilter].includes(event));
+      const hasInvalidEvent = accepts?.some(
+        (event) => ![...Object.values(graphQLEvents), ...Object.values(appEvents)].includes(event)
+      );
 
       const hasInvalidNetwork = allowNetworks.find((netWork) => !isValidNetwork(netWork));
       if (hasInvalidNetwork) {
         console.log(
           `${chalk.red(
-            'Error:',
+            'Error:'
           )} Invalid IP address ${hasInvalidNetwork} found in the allowNetworks array for ${type} "${
             item.name
-          }".`,
+          }".`
         );
         // eslint-disable-next-line no-process-exit
         process.exit(1);
@@ -135,10 +148,10 @@ export function getEntityFromManifest<Type extends 'actions' | 'functions'>(type
       if (hasInvalidEvent) {
         console.log(
           `${chalk.red(
-            'Error:',
+            'Error:'
           )} Invalid events ${hasInvalidEvent} found in the accepts array for ${type} "${
             item.name
-          }".`,
+          }".`
         );
         // eslint-disable-next-line no-process-exit
         process.exit(1);
@@ -159,8 +172,8 @@ export function getEntityFromManifest<Type extends 'actions' | 'functions'>(type
   } catch {
     console.log(
       `${chalk.red('Error:')} Invalid JSON in manifest file at ${chalk.bold(
-        DEFAULT_MANIFEST_PATH,
-      )}.`,
+        DEFAULT_MANIFEST_PATH
+      )}.`
     );
     // eslint-disable-next-line no-process-exit
     process.exit(1);
diff --git a/packages/contentful--create-contentful-app/README.md b/packages/contentful--create-contentful-app/README.md
index ccd65d0bb..59fd902b0 100644
--- a/packages/contentful--create-contentful-app/README.md
+++ b/packages/contentful--create-contentful-app/README.md
@@ -17,7 +17,7 @@ To start developing your first app, run:
 npx create-contentful-app my-first-app
 ```
 
-![Screenshot of `npx create-contentful-app my-app`](https://raw.githubusercontent.com/contentful/create-contentful-app/master/packages/contentful--create-contentful-app/docs/screenshot.png)
+![Screenshot of `npx create-contentful-app my-app`](https://raw.githubusercontent.com/contentful/create-contentful-app/main/packages/contentful--create-contentful-app/docs/screenshot.png)
 
 ## Bootstrap
 
diff --git a/packages/contentful--create-contentful-app/src/includeFunction.ts b/packages/contentful--create-contentful-app/src/includeFunction.ts
index 0c87d6825..9930b0459 100644
--- a/packages/contentful--create-contentful-app/src/includeFunction.ts
+++ b/packages/contentful--create-contentful-app/src/includeFunction.ts
@@ -11,7 +11,12 @@ const addBuildCommand = getAddBuildCommandFn({
   command: 'node build-functions.js',
 });
 
-const VALID_FUNCTION_TEMPLATES_DIRS = ['templates', 'appevent-filter'];
+const VALID_FUNCTION_TEMPLATES_DIRS = [
+  'templates',
+  'appevent-filter',
+  'appevent-handler',
+  'appevent-transformation',
+];
 
 function functionTemplateFromName(functionName: string) {
   let dirName = functionName;