Save several app files

curl --request POST \
  --url https://app.base44.com/api/apps/{app_id}/coding/write-batch \
  --header 'Content-Type: application/json' \
  --header 'api_key: <api-key>' \
  --data '
{
  "files": [
    {
      "file_path": "src/pages/About.jsx",
      "content": "export default function About() {\n  return <h1>About</h1>;\n}\n"
    },
    {
      "file_path": "src/pages/Home.jsx",
      "content": "export default function Home() {\n  return <h1>Home</h1>;\n}\n"
    }
  ]
}
'

import requests

url = "https://app.base44.com/api/apps/{app_id}/coding/write-batch"

payload = { "files": [
        {
            "file_path": "src/pages/About.jsx",
            "content": "export default function About() {
  return <h1>About</h1>;
}
"
        },
        {
            "file_path": "src/pages/Home.jsx",
            "content": "export default function Home() {
  return <h1>Home</h1>;
}
"
        }
    ] }
headers = {
    "api_key": "<api-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {api_key: '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    files: [
      {
        file_path: 'src/pages/About.jsx',
        content: 'export default function About() {\n  return <h1>About</h1>;\n}\n'
      },
      {
        file_path: 'src/pages/Home.jsx',
        content: 'export default function Home() {\n  return <h1>Home</h1>;\n}\n'
      }
    ]
  })
};

fetch('https://app.base44.com/api/apps/{app_id}/coding/write-batch', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://app.base44.com/api/apps/{app_id}/coding/write-batch",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'files' => [
        [
                'file_path' => 'src/pages/About.jsx',
                'content' => 'export default function About() {
  return <h1>About</h1>;
}
'
        ],
        [
                'file_path' => 'src/pages/Home.jsx',
                'content' => 'export default function Home() {
  return <h1>Home</h1>;
}
'
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "api_key: <api-key>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://app.base44.com/api/apps/{app_id}/coding/write-batch"

	payload := strings.NewReader("{\n  \"files\": [\n    {\n      \"file_path\": \"src/pages/About.jsx\",\n      \"content\": \"export default function About() {\\n  return <h1>About</h1>;\\n}\\n\"\n    },\n    {\n      \"file_path\": \"src/pages/Home.jsx\",\n      \"content\": \"export default function Home() {\\n  return <h1>Home</h1>;\\n}\\n\"\n    }\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("api_key", "<api-key>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://app.base44.com/api/apps/{app_id}/coding/write-batch")
  .header("api_key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"files\": [\n    {\n      \"file_path\": \"src/pages/About.jsx\",\n      \"content\": \"export default function About() {\\n  return <h1>About</h1>;\\n}\\n\"\n    },\n    {\n      \"file_path\": \"src/pages/Home.jsx\",\n      \"content\": \"export default function Home() {\\n  return <h1>Home</h1>;\\n}\\n\"\n    }\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://app.base44.com/api/apps/{app_id}/coding/write-batch")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["api_key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"files\": [\n    {\n      \"file_path\": \"src/pages/About.jsx\",\n      \"content\": \"export default function About() {\\n  return <h1>About</h1>;\\n}\\n\"\n    },\n    {\n      \"file_path\": \"src/pages/Home.jsx\",\n      \"content\": \"export default function Home() {\\n  return <h1>Home</h1>;\\n}\\n\"\n    }\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "id": "6820f3a4e7b91d003c45a1f2",
  "name": "My CRM",
  "slug": "my-crm-3c45a1f2",
  "user_description": "A CRM to track leads and deals",
  "created_by": "developer@example.com",
  "created_date": "2026-08-01T09:15:00",
  "updated_date": "2026-08-02T14:30:00",
  "status": {
    "state": "ready",
    "details": "Publishing app",
    "request_id": "a1b2c3d4e5f67890abcdef12",
    "last_updated_date": "2026-08-02T14:30:00Z",
    "error_source": "build",
    "paywall_context": {
      "billing_organization_id": "67e0b12c4d8a3f005b21c9e4",
      "user_id": "6706af53b9c1e2004a37d85f",
      "evaluated_at": "2026-08-02T14:30:00Z"
    }
  },
  "last_deployed_at": "2026-08-02T14:30:00",
  "screenshot_url": "https://storage.base44.com/screenshots/6820f3a4e7b91d003c45a1f2.png",
  "preview_screenshot_url": "https://storage.base44.com/previews/6820f3a4e7b91d003c45a1f2.png"
}

Code

Save several app files

This API is in beta. Endpoints, fields, and behavior may still change, so avoid depending on it in production.

Saves several files into the app in one call, the way the builder’s visual editor does.

Send up to 50 files. Every path is validated before anything is written, so one bad path fails the whole batch with a 400 and leaves the app untouched. An empty files list is a 400 rather than a no-op.

This route never deploys, so it refuses backend code: a path under functions/ answers 422 rather than writing source that the live function wouldn’t match. Use Save an app file for those, one at a time, and this one for the frontend files a visual edit touches.

Unlike the single-file route, this one follows the branch you are working on, so the writes land on that branch’s own sandbox rather than on main.

The response is the app document as it stands after the change, the same shape Get app returns.

This endpoint accepts a personal API key. Workspace API keys are not authorized for it and are rejected with a 403.

The response includes fields beyond the ones documented here. Don’t rely on undocumented response fields, as they can change at any time. Send only the fields documented here. Other request fields are not supported and their behavior can change.

POST

api

apps

{app_id}

coding

write-batch

Save several app files

curl --request POST \
  --url https://app.base44.com/api/apps/{app_id}/coding/write-batch \
  --header 'Content-Type: application/json' \
  --header 'api_key: <api-key>' \
  --data '
{
  "files": [
    {
      "file_path": "src/pages/About.jsx",
      "content": "export default function About() {\n  return <h1>About</h1>;\n}\n"
    },
    {
      "file_path": "src/pages/Home.jsx",
      "content": "export default function Home() {\n  return <h1>Home</h1>;\n}\n"
    }
  ]
}
'

import requests

url = "https://app.base44.com/api/apps/{app_id}/coding/write-batch"

payload = { "files": [
        {
            "file_path": "src/pages/About.jsx",
            "content": "export default function About() {
  return <h1>About</h1>;
}
"
        },
        {
            "file_path": "src/pages/Home.jsx",
            "content": "export default function Home() {
  return <h1>Home</h1>;
}
"
        }
    ] }
headers = {
    "api_key": "<api-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {api_key: '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    files: [
      {
        file_path: 'src/pages/About.jsx',
        content: 'export default function About() {\n  return <h1>About</h1>;\n}\n'
      },
      {
        file_path: 'src/pages/Home.jsx',
        content: 'export default function Home() {\n  return <h1>Home</h1>;\n}\n'
      }
    ]
  })
};

fetch('https://app.base44.com/api/apps/{app_id}/coding/write-batch', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://app.base44.com/api/apps/{app_id}/coding/write-batch",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'files' => [
        [
                'file_path' => 'src/pages/About.jsx',
                'content' => 'export default function About() {
  return <h1>About</h1>;
}
'
        ],
        [
                'file_path' => 'src/pages/Home.jsx',
                'content' => 'export default function Home() {
  return <h1>Home</h1>;
}
'
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "api_key: <api-key>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://app.base44.com/api/apps/{app_id}/coding/write-batch"

	payload := strings.NewReader("{\n  \"files\": [\n    {\n      \"file_path\": \"src/pages/About.jsx\",\n      \"content\": \"export default function About() {\\n  return <h1>About</h1>;\\n}\\n\"\n    },\n    {\n      \"file_path\": \"src/pages/Home.jsx\",\n      \"content\": \"export default function Home() {\\n  return <h1>Home</h1>;\\n}\\n\"\n    }\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("api_key", "<api-key>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://app.base44.com/api/apps/{app_id}/coding/write-batch")
  .header("api_key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"files\": [\n    {\n      \"file_path\": \"src/pages/About.jsx\",\n      \"content\": \"export default function About() {\\n  return <h1>About</h1>;\\n}\\n\"\n    },\n    {\n      \"file_path\": \"src/pages/Home.jsx\",\n      \"content\": \"export default function Home() {\\n  return <h1>Home</h1>;\\n}\\n\"\n    }\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://app.base44.com/api/apps/{app_id}/coding/write-batch")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["api_key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"files\": [\n    {\n      \"file_path\": \"src/pages/About.jsx\",\n      \"content\": \"export default function About() {\\n  return <h1>About</h1>;\\n}\\n\"\n    },\n    {\n      \"file_path\": \"src/pages/Home.jsx\",\n      \"content\": \"export default function Home() {\\n  return <h1>Home</h1>;\\n}\\n\"\n    }\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "id": "6820f3a4e7b91d003c45a1f2",
  "name": "My CRM",
  "slug": "my-crm-3c45a1f2",
  "user_description": "A CRM to track leads and deals",
  "created_by": "developer@example.com",
  "created_date": "2026-08-01T09:15:00",
  "updated_date": "2026-08-02T14:30:00",
  "status": {
    "state": "ready",
    "details": "Publishing app",
    "request_id": "a1b2c3d4e5f67890abcdef12",
    "last_updated_date": "2026-08-02T14:30:00Z",
    "error_source": "build",
    "paywall_context": {
      "billing_organization_id": "67e0b12c4d8a3f005b21c9e4",
      "user_id": "6706af53b9c1e2004a37d85f",
      "evaluated_at": "2026-08-02T14:30:00Z"
    }
  },
  "last_deployed_at": "2026-08-02T14:30:00",
  "screenshot_url": "https://storage.base44.com/screenshots/6820f3a4e7b91d003c45a1f2.png",
  "preview_screenshot_url": "https://storage.base44.com/previews/6820f3a4e7b91d003c45a1f2.png"
}

Authorizations

api_key

string

header

required

Personal API key.

Path Parameters

app_id

string

required

ID of the app whose code to change.

Body

application/json

files

SaveAppFilesEntry · object[]

required

The files to save, 1 to 50 of them. All are validated before any is written.

Required array length: 1 - 50 elements

Show child attributes

Response

The app after the writes.

An app in a workspace, limited to the properties the caller requested.

string | null

ID of the app.

Example:

"6820f3a4e7b91d003c45a1f2"

name

string | null

Display name of the app.

Example:

"My CRM"

slug

string | null

URL slug for the app, auto generated from the name and app ID or set to a custom value, or null if the app has no slug yet. The published URL is built from it.

Example:

"my-crm-3c45a1f2"

user_description

string | null

Description of the app, or null if none was set. On a newly created app this holds the original prompt text.

Example:

"A CRM to track leads and deals"

created_by

string | null

Email of the user who created the app.

Example:

"developer@example.com"

created_date

string<date-time> | null

Time the app was created, as a UTC timestamp in ISO 8601 format.

Example:

"2026-08-01T09:15:00"

updated_date

string<date-time> | null

Time the app document was last written, as a UTC timestamp in ISO 8601 format.

Example:

"2026-08-02T14:30:00"

status

AppStatusResponse · object | null

The app's current build status. Poll while a build is in progress to watch it finish. This tracks building, not publishing.

Show child attributes

last_deployed_at

string<date-time> | null

Time the app was last published, as a UTC timestamp in ISO 8601 format, or null if it has never been published.

Example:

"2026-08-02T14:30:00"

screenshot_url

string | null

URL of a screenshot of the published app. Captured shortly after each publish, so it can briefly lag or be null right after publishing.

Example:

"https://storage.base44.com/screenshots/6820f3a4e7b91d003c45a1f2.png"

preview_screenshot_url

string | null

URL of a preview screenshot taken before publishing, distinct from screenshot_url, or null if none has been captured.

Example:

"https://storage.base44.com/previews/6820f3a4e7b91d003c45a1f2.png"

Base44 APIs

Apps API (Beta)

Monitoring API

Audit Logs API

Save several app files

Authorizations

Path Parameters

Body

Response