25% of Y Combinator's W25 batch have codebases that are 95% AI-generated. TechCrunch: 25% of YC W25 have 95%+ AI-generated codebases What counted as a competitive edge a year ago is now a risk factor in technical due diligence (TDD): AI-generated code contains security vulnerabilities in 45% of cases, is rarely tested, and builds up technical debt that can mean as much as a 20% discount at valuation. For CTOs and investors evaluating AI-built platforms, a new set of review criteria applies.
Why the pace of AI is changing technical due diligence
The speed at which AI tools turn out working code has created a new problem: platforms look convincing in the demo but are technically fragile. YC CEO Garry Tan captured the trend in a single line: "The age of vibe coding is here." Garry Tan: The age of vibe coding is here (2025) A TDD audit surfaces exactly the shortcuts a demo never reveals: missing tests, exposed secrets, inconsistent architecture.
Gartner forecasts that more than 40% of all agentic-AI projects will be scrapped by the end of 2027 – driven by escalating costs, unclear business value, or inadequate risk controls. Gartner: 40%+ Agentic AI Projects Canceled by 2027 That is why investors now scrutinize AI-built platforms more closely: test coverage, secrets hygiene, and architectural consistency, before the term sheet hits the table.
Red flags: what stands out in AI-generated codebases
No test coverage
AI tools generate functional code, but almost never the tests to go with it. A platform without unit tests, integration tests, and E2E tests is flying blind – no investor accepts that as production-ready. In due diligence, test coverage below 60% is an immediate red flag.
Hardcoded secrets and API keys
In 2025, more than 28.6 million new hardcoded secrets were discovered in public GitHub commits – a 34% increase year over year. OECD.AI: AI Coding Assistants Drive Surge in Secret Leaks Repositories with GitHub Copilot active show a roughly 40% higher rate of exposed secrets (6.4% vs. 4.6% of all public repositories): API keys, database passwords, and tokens sitting directly in the source code. GitGuardian: GitHub Copilot and the risk of leaked secrets
Missing error handling
AI-generated code focuses on the happy path. Edge cases, error handling, retry logic, and graceful degradation are systematically absent – which leads to cascading failures in production.
Inconsistent architecture
Dependency bloat
AI models add dependencies without checking what is already in place. The result is dozens of redundant packages and outdated versions piling up – a bloated supply chain that widens the attack surface.
No CI/CD pipeline
Without continuous integration, there are no automated checks – no lint enforcement, no security scans, no automated deployments. Every release is a manual risk.
Missing access control
AI agents routinely forget to wire authentication middleware into downstream components. The result: individual routes or API endpoints are left unprotected, even when a login page exists. The Hacker News: AI Code Expands Attack Surface (2026)
The valuation impact: as much as a 20% discount
Technical debt feeds straight into company valuation. Technical findings in due diligence can knock as much as 20% off the valuation, and roughly 60% of deals fall through over problems that only surface in the tech review. Sphere: Technical due diligence can cut valuation by up to 20%
| Kriterium | Production-Ready Codebase | Vibe-Coded Platform |
|---|---|---|
| Test coverage | > 70% with CI enforcement | 0–5%, no automated tests |
| Security scans | SAST/DAST integrated into CI/CD | No scans, no audits |
| Secrets management | Vault/ENV, no secrets in code | Hardcoded API keys in .env files |
| Architecture | Consistent patterns, documented | Incoherent, generated file by file |
| Dependency management | Automated updates, SBOM | Outdated packages, no tracking |
| Error handling | Retry logic, circuit breaker, logging | None – happy path only |
| Valuation impact | Full valuation | Up to 20% discount |
A worked example: three additional senior engineers over twelve months, at a fully loaded headcount cost of €110,000–180,000 per person, amount to roughly €330,000–540,000 in extra spend that investors deduct from the valuation.
What a TDD report must contain
A professional technical due diligence report for AI-built platforms covers:
- Architecture assessment: System architecture, data model, API design, consistency of patterns
- Code quality analysis: Automated scans (SonarQube, Snyk), technical debt quantified
- Security audit: SAST/DAST results, secrets scan, dependency vulnerabilities, OWASP Top 10
- Infrastructure review: Deployment process, monitoring, backup strategy, scalability
- Team assessment: Technical capability, documentation, development processes
- Compliance check: GDPR, NIS2, data residency, supply chain security
- Risk assessment: A prioritized list with estimated remediation effort and timeline
How to make your codebase audit-ready
Quick wins (weeks 1–2):
- Run a secrets scan and strip out every hardcoded credential
- Dependency audit: run
npm audit/yarn auditand apply critical updates - Stand up a basic CI/CD pipeline with linting and security checks
Short term (months 1–2):
- Build out a test suite: cover critical business logic at minimum
- Produce architecture documentation
- Implement monitoring and logging (Grafana + Prometheus)
Medium term (months 2–4):
- Security hardening: RBAC, MFA, rate limiting
- Infrastructure as code (Terraform) for reproducible deployments
- Establish a performance baseline and run load tests
In a free intro conversation, we assess your AI-built platform for TDD readiness – from security findings to architectural weaknesses. We deliver the full build at a fixed price of €36,000: a working app on EU-sovereign infrastructure.
Frequently asked questions
What is a technical due diligence?
How does technical debt affect valuation?
What are the most common red flags in AI-generated codebases?
When should I make my codebase audit-ready?
Is Gartner's forecast on AI project failure taken seriously?
Can AnvilStack help with TDD preparation?
Sources
- TechCrunch: 25% of YC W25 Startups Have 95%+ AI-Generated Codebases
- Garry Tan: The Age of Vibe Coding Is Here (2025)
- Gartner: 40%+ Agentic AI Projects Canceled by 2027
- Veracode: GenAI Code Security Report 2025
- OECD.AI: AI Coding Assistants Drive Surge in Secret Leaks on GitHub
- Escape.tech: 2,000+ vulnerabilities and 400+ secrets across 5,600 vibe-coded apps
- GitGuardian: GitHub Copilot and the risk of leaked secrets
- The Hacker News: AI Code Expands Attack Surface (2026)
- Sphere: Technical due diligence can cut valuation by up to 20%
- Cleveroad: Technical Due Diligence Key Elements 2025
- DextraLabs: Software M&A Technical Due Diligence 2026
- LeadDev: How AI Generated Code Accelerates Technical Debt
- HackerNoon: The Vibe Coding Hangover