Builder.ai Stranded? The Complete Migration Guide (2026)

Quick triage: what is your situation?

Before diving into the full guide, find your row in the table below. Each situation calls for a different first move.

What happened to Builder.ai

Builder.ai (formerly Engineer.ai) was a London-based startup that promised businesses they could describe an app in plain English and have it built automatically by AI. The company raised approximately $450 million from investors including Microsoft, the Qatar Investment Authority, and others. At its peak it was valued at more than $1.3 billion.

The collapse came in stages. In early 2025, Bloomberg and other outlets reported that Builder.ai had allegedly overstated its revenue by more than $100 million. Shortly after, Israeli lending firm Viola Credit seized most of the company's cash under the terms of a debt facility. With liquidity gone, Builder.ai entered formal insolvency proceedings in the UK on approximately May 20, 2025, appointing a court-approved administrator.

The underlying product controversy: Builder.ai marketed its “Natasha” AI as an automated app-building engine. Investigations by Rest of World and other journalists found that the vast majority of actual development work was performed by human contractors — reportedly around 700 engineers, many in India — with the AI handling at most routine template-matching tasks. This was not disclosed to customers in a meaningful way.

What matters practically: the company is in administration, its servers may be decommissioned, and there is no normal customer support channel. Whatever you can do to recover assets needs to happen quickly.

What you can actually recover from Builder.ai

The hard truth first: Builder.ai used a proprietary platform. Most customers did not receive a Git repository or deployable codebase as part of the engagement. That said, the picture is not uniformly bleak. Here is what may be recoverable, in order of likelihood:

How to extract your data right now

Time-sensitive: the Builder.ai portal may be accessible on some days and not others as administrators manage server costs. Do this today if you have not already.

Step A: Screenshot and record every screen

Use a tool like Screenpresso or the browser extension Full Page Screen Capture to take full-page screenshots of every view in your app: dashboard, forms, user flows, admin panels. These become your rebuild blueprint.

Step B: Export data via the dashboard

In the Builder.ai project portal, look for any “Export” or “Download” options in data tables, CRM views, and reporting sections. Export as CSV. Even if the format is messy, raw data is salvageable.

Step C: Try the Builder.ai API (if your plan included API access)

Some Builder.ai tiers exposed a REST API. If you have an API key in your account settings, try pulling your data programmatically before the endpoints go offline. A minimal Node.js script to test access:

// test-builder-export.js
// Run with: node test-builder-export.js
// Replace YOUR_API_KEY and YOUR_PROJECT_ID
const BASE_URL = 'https://api.builder.ai/v1';
const API_KEY  = 'YOUR_API_KEY';
const PROJECT  = 'YOUR_PROJECT_ID';
async function tryExport() {
  try {
    const res = await fetch(`${BASE_URL}/projects/${PROJECT}/data`, {
      headers: { 'Authorization': `Bearer ${API_KEY}` }
    });
    if (res.ok) {
      const data = await res.json();
      require('fs').writeFileSync(
        `builder-export-${Date.now()}.json`,
        JSON.stringify(data, null, 2)
      );
      console.log('Export saved.');
    } else {
      console.log(`API returned ${res.status} - endpoint may be offline.`);
    }
  } catch (err) {
    console.log('Connection failed:', err.message);
  }
}
tryExport();

Note: This script tests whether Builder.ai's API is still responding. If it returns a 404 or connection error, the endpoint is likely down. This is a diagnostic, not a guaranteed export path.

Step D: Contact the insolvency administrator

Builder.ai's UK insolvency is administered by a court-appointed firm. Search Companies House (beta.companieshouse.gov.uk) for “Builder.ai” to find the appointed administrator's name and contact details. Write a formal letter stating your customer status, the IP you paid to create, and requesting access to your project assets. Attach your original contract, invoices, and any project delivery receipts. This is a legitimate creditor action under UK insolvency law.

Migration paths: where to go next

Where you migrate depends on three factors: how technical your team is, how complex your app is, and how much ongoing maintenance flexibility you need. The table below maps common situations to recommended stacks.

Step-by-step migration playbook

# validate-import.py
import pandas as pd
from supabase import create_client
SUPABASE_URL = "YOUR_SUPABASE_URL"
SUPABASE_KEY = "YOUR_SUPABASE_ANON_KEY"
TABLE        = "your_table_name"
ORIGINAL_CSV = "builder-export.csv"
client = create_client(SUPABASE_URL, SUPABASE_KEY)
original = pd.read_csv(ORIGINAL_CSV)
print(f"Source rows: {len(original)}")
response = client.table(TABLE).select("id", count="exact").execute()
print(f"Destination rows: {response.count}")
if len(original) == response.count:
    print("Row counts match. Spot-check 20 records manually.")
else:
    print(f"MISMATCH: {len(original) - response.count} rows missing.")

Common scenarios with solutions

The right migration path depends heavily on what kind of app you had. Here are the four most common Builder.ai customer types and the recommended approach for each.

What it costs and how long it takes

These are realistic ranges based on typical migration and rebuild projects. Costs assume you are hiring an experienced developer or agency. DIY with AI tools (Lovable, Bolt) reduces cost significantly but increases your time investment.

All figures are estimates. Actual costs depend on app complexity, data volume, and chosen stack. AppStuck provides fixed-price quotes after a free assessment.

For reference: Builder.ai customers typically paid anywhere from a few thousand pounds (Studio Store plans at roughly GBP 75/month over 24 months) to tens of thousands for custom builds. A migration to an owned stack at these prices is often less than what was originally paid to Builder.ai.

Red flags: mistakes to avoid when migrating

Legal considerations for Builder.ai customers

This section is general information, not legal advice. Consult a qualified solicitor for advice specific to your situation.

IP ownership: what does your contract say?

Builder.ai's standard contracts typically assigned intellectual property to the customer upon full payment. If you paid in full and have a contract clause confirming IP transfer, you have a documented claim to your source code. Locate your original contract and find the IP ownership clause before contacting the administrator.

Filing a creditor claim

As a customer who paid for services not fully delivered, you may have standing as an unsecured creditor in the UK insolvency process. Typical steps:

1. Search Companies House for the appointed administrator's details (beta.companieshouse.gov.uk, search “Builder.ai Limited”).
2. Submit a formal Proof of Debt form to the administrator with your contract, invoices, and a statement of what was not delivered.
3. Be realistic: unsecured creditors typically recover a small fraction (often 0–20 pence per pound) in insolvency proceedings, and it can take 12–24 months.

Insurance claims

Some businesses hold trade credit insurance or business interruption insurance that may cover losses from a key supplier's insolvency. Review your business insurance policy and contact your broker to check coverage.

GDPR and data protection obligations

If your Builder.ai app stored personal data about your customers (names, emails, purchase history), you retain data controller obligations under GDPR even though Builder.ai — as data processor — has ceased operations. You should notify your users if their data may be at risk, document the incident, and retrieve and secure user data before servers go offline.

Chargebacks (for recent payments)

If you made a payment to Builder.ai in the 60–120 days prior to the insolvency, you may be able to raise a chargeback with your credit card provider for services not rendered. Act quickly — chargeback windows are typically 60–120 days from the transaction date, depending on your card network.

Frequently asked questions

When to call an expert

The playbook in this guide is designed to be actionable without outside help for simple apps. But there are situations where trying to DIY will cost you more time and money than hiring an expert from day one:

AppStuck's AI app rescue service is built specifically for situations like Builder.ai migrations. We have handled rescues with no source code, with partial codebases, with live user bases, and with tight deadlines. See the Builder.ai platform page for more context on what we typically find in these projects.

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