What Should Technical
Due Diligence Cover?

Quick Take

Technical due diligence should assess five areas: architecture and scalability, code quality and maintainability, security and compliance, team capability and knowledge distribution, and infrastructure and DevOps maturity. A thorough assessment takes 1-3 weeks depending on complexity and should be conducted by an independent senior technologist, not the target company itself. The goal is to surface risks that affect valuation, integration cost, or post-deal execution.

1. Architecture & Scalability

• ☐  Is the architecture documented and does the documentation match reality?
• ☐  Can the system scale to 10x current load without a fundamental rewrite?
• ☐  Are there single points of failure that could cause complete outages?
• ☐  Is the technology stack current and supported, or approaching end-of-life?
• ☐  Are integrations with third-party services well-abstracted and replaceable?
• ☐  Is there a clear separation between business logic, data, and presentation?

2. Code Quality & Maintainability

• ☐  What is the automated test coverage and are tests meaningful or superficial?
• ☐  Is the codebase consistent in style, patterns, and naming conventions?
• ☐  How much accumulated technical debt exists and is it being actively managed?
• ☐  Are dependencies up to date and free of known vulnerabilities?
• ☐  Is the code modular enough that new developers can be productive within weeks?
• ☐  Is there a code review process in place and is it actually followed?

3. Security & Compliance

• ☐  Has the application had a security audit or penetration test recently?
• ☐  Is sensitive data encrypted at rest and in transit?
• ☐  Are authentication and authorisation implemented correctly?
• ☐  Is the system GDPR-compliant (data retention, deletion, consent)?
• ☐  Are secrets, API keys, and credentials properly managed (not hardcoded)?
• ☐  Is there an incident response plan and has it been tested?

4. Team & Knowledge Distribution

• ☐  Is critical knowledge spread across the team or concentrated in one person?
• ☐  Are team members experienced enough for the complexity of the system?
• ☐  Is there a risk of key-person dependency (what if the lead developer leaves)?
• ☐  Are roles and responsibilities clearly defined?
• ☐  Is there a hiring pipeline and can the team scale?

5. Infrastructure & DevOps

• ☐  Is infrastructure defined as code and reproducible?
• ☐  Is there a CI/CD pipeline with automated testing and deployment?
• ☐  Are backups automated, tested, and sufficient for disaster recovery?
• ☐  Is monitoring and alerting in place for key business and technical metrics?
• ☐  What is the deployment frequency and how long does a deployment take?
• ☐  Are environments (dev, staging, production) properly separated?