Financial due diligence tells you what happened. Technical due diligence tells you what will break after you sign.

Whether you are acquiring a product, leading a Series A, or selling your company, the same engineering questions apply — only the stakes change.

1. Architecture snapshot (one diagram)

Ask for a current diagram:

  • Users → CDN → app → APIs → databases → third parties
  • Background workers and queues
  • Where PII is stored and who can access it

If no one can draw it in 30 minutes, that is data.

2. Codebase health signals

You do not need to read every file. Sample:

  • Dependency age and known CVEs (npm audit, etc.)
  • Test coverage on billing, auth, and permissions — not only utils
  • Deployment frequency in the last 90 days
  • Mean time to restore from last incident

3. Metrics integrity

Product metrics must reconcile:

  • Billing (Stripe) vs in-app “active users”
  • Analytics vs database counts for signups

Red flags: manual spreadsheet “truth” for board decks.

4. Security basics

Minimum bar for B2B SaaS:

  • SSO/SAML if enterprise customers exist
  • Encryption at rest and in transit
  • Secrets not in git history
  • Pen test or third-party assessment for mature ARR

Review OWASP ASVS as a conversation framework.

5. Infrastructure and cost

  • Monthly cloud bill trend vs revenue
  • Single points of failure (one region, one DB, one engineer who deploys)
  • Backup restore test date — when, not if

6. Team and bus factor

  • Who owns on-call?
  • What happens if the lead engineer leaves?
  • Is documentation enough for a new senior hire in week one?
  • Open-source license compliance
  • Customer data processing agreements
  • Subprocessors list matches actual vendors

When to bring specialists

Acquirers often hire a senior dev partner for a fixed-scope technical DD — cheaper than discovering debt post-close.

Founders preparing for exit should run the same checklist six months early and fix the cheap wins.

Related: Hiring vs subscription economics · MVP scoping

Request a technical review if you need an independent engineering perspective.

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