diff --git a/backend/forum/functions/createPost/config.ts b/backend/forum/functions/createPost/config.ts
new file mode 100644
index 00000000..07a37fce
--- /dev/null
+++ b/backend/forum/functions/createPost/config.ts
@@ -0,0 +1,13 @@
+import { createPostContract } from '@swarmion-starter/forum-contracts';
+import {
+  getHandlerPath,
+  LambdaFunction,
+} from '@swarmion-starter/serverless-helpers';
+
+const config: LambdaFunction = {
+  environment: {},
+  handler: getHandlerPath(__dirname),
+  events: [createPostContract.trigger],
+};
+
+export default config;
diff --git a/backend/forum/functions/createPost/handler.mock.json b/backend/forum/functions/createPost/handler.mock.json
new file mode 100644
index 00000000..049ce9a2
--- /dev/null
+++ b/backend/forum/functions/createPost/handler.mock.json
@@ -0,0 +1,4 @@
+{
+  "pathParameters": { "threadId": "fooBar" },
+  "body": { "content": "Hello, I am Swarmion!" }
+}
diff --git a/backend/forum/functions/createPost/handler.test.ts b/backend/forum/functions/createPost/handler.test.ts
new file mode 100644
index 00000000..5bd48337
--- /dev/null
+++ b/backend/forum/functions/createPost/handler.test.ts
@@ -0,0 +1,14 @@
+import { handler } from './handler';
+
+describe('createPost handler', () => {
+  it('should return a post with the created content', async () => {
+    const postContent = 'Hello from Swarmion';
+
+    const { content } = await handler({
+      pathParameters: { threadId: 'blob' },
+      body: { content: postContent },
+    });
+
+    expect(content).toEqual(postContent);
+  });
+});
diff --git a/backend/forum/functions/createPost/handler.ts b/backend/forum/functions/createPost/handler.ts
new file mode 100644
index 00000000..0c688231
--- /dev/null
+++ b/backend/forum/functions/createPost/handler.ts
@@ -0,0 +1,21 @@
+import { createPostContract } from '@swarmion-starter/forum-contracts';
+import { applyHttpMiddlewares } from '@swarmion-starter/serverless-helpers';
+
+export const handler = createPostContract.handler(async event => {
+  const { threadId } = event.pathParameters;
+  const { content } = event.body;
+
+  await Promise.resolve({ threadId });
+
+  return {
+    id: 'myFirstPost',
+    createdAt: '2021-10-25T12:12:00Z',
+    editedAt: null,
+    content,
+    authorId: 'author2',
+  };
+});
+
+export const main = applyHttpMiddlewares(handler, {
+  inputSchema: createPostContract.inputSchema,
+});
diff --git a/backend/forum/functions/index.ts b/backend/forum/functions/index.ts
index 00188fca..f9b2e55a 100644
--- a/backend/forum/functions/index.ts
+++ b/backend/forum/functions/index.ts
@@ -1,3 +1,4 @@
+import createPost from './createPost/config';
 import getThreadAndPosts from './getThreadAndPosts/config';
 
-export const functions = { getThreadAndPosts };
+export const functions = { getThreadAndPosts, createPost };
diff --git a/contracts/forum-contracts/src/contracts/requests/createPost.ts b/contracts/forum-contracts/src/contracts/requests/createPost.ts
new file mode 100644
index 00000000..03645b05
--- /dev/null
+++ b/contracts/forum-contracts/src/contracts/requests/createPost.ts
@@ -0,0 +1,33 @@
+import { ApiGatewayContract } from '@swarmion/serverless-contracts';
+
+import { postEntitySchema } from 'contracts/entities';
+
+const pathParametersSchema = {
+  type: 'object',
+  properties: {
+    threadId: { type: 'string' },
+  },
+  required: ['threadId'],
+  additionalProperties: false,
+} as const;
+
+const bodySchema = {
+  type: 'object',
+  properties: {
+    content: { type: 'string' },
+  },
+  required: ['content'],
+  additionalProperties: false,
+} as const;
+
+export const createPostContract = new ApiGatewayContract({
+  id: 'forum-createPost',
+  path: '/forum/thread/{threadId}',
+  method: 'POST',
+  integrationType: 'httpApi',
+  pathParametersSchema,
+  queryStringParametersSchema: undefined,
+  bodySchema,
+  headersSchema: undefined,
+  outputSchema: postEntitySchema,
+});
diff --git a/contracts/forum-contracts/src/contracts/requests/index.ts b/contracts/forum-contracts/src/contracts/requests/index.ts
index 60645ec6..4640663c 100644
--- a/contracts/forum-contracts/src/contracts/requests/index.ts
+++ b/contracts/forum-contracts/src/contracts/requests/index.ts
@@ -1 +1,2 @@
 export * from './getThreadWithPosts';
+export * from './createPost';