Evaluate a Dev Agency's Tech Stack

An agency's technology choices determine whether your product will scale, be maintainable, and remain secure for years to come. This guide helps you assess technical capabilities before signing a contract.

Why Tech Stack Matters

Choosing the right technology isn't just about what's trendy—it's about what works for your specific product. An agency that claims to use React, Node.js, and PostgreSQL but has never built with them will deliver a product that's harder to maintain and more expensive to scale later.

The wrong tech stack can cost you hundreds of thousands of dollars in technical debt. The right one sets you up for success.

Key Things to Verify

1. Frontend Framework Experience

The agency should be proficient with modern frameworks like React, Vue, or Angular. Ask them to explain their approach to component architecture, state management, and performance optimization. If they struggle to answer specific questions about hooks, context, or routing, that's a red flag.

Have them show you a production app they built and discuss how they structured the code.

2. Backend Architecture

Does the agency build scalable APIs? Ask about their approach to authentication, database design, caching, and how they handle increasing load. They should be familiar with concepts like pagination, rate limiting, and asynchronous processing.

If they're building your SaaS product, they should have strong experience with multi-tenancy and security.

3. Database & Infrastructure Choices

Modern apps use PostgreSQL, MongoDB, or other proven databases. Ask why they chose their database for your specific needs. Understand their hosting strategy—are they using cloud providers like AWS, Google Cloud, or Azure? Can they explain auto-scaling, backup strategies, and disaster recovery?

Agencies that host on outdated shared servers are a major red flag for scalability.

4. Security Practices

Ask about their approach to security. Do they follow OWASP guidelines? How do they handle data encryption, API authentication, and third-party vulnerabilities? Are they familiar with security testing and penetration testing?

A strong agency will have security integrated throughout their development process, not added at the end.

5. DevOps & Deployment

How do they deploy code? Do they use continuous integration/continuous deployment (CI/CD)? Can they explain containerization with Docker or orchestration with Kubernetes? Modern agencies should have automated testing and zero-downtime deployment.

Manual deployments and lack of monitoring are signs of outdated practices.

Using the Tech Scanner Tool

Our Tech Scanner makes verification easy. Simply scan an agency's website or portfolio to get:

• Their verified technology stack
• Frontend frameworks and libraries in use
• Backend languages and frameworks
• Hosting providers and infrastructure
• Security headers and SSL configuration
• Performance optimization indicators

This gives you concrete evidence of what technologies they actually use, not just what they claim to use.

Questions to Ask

Use these specific questions during your evaluation:

• "Can you walk me through how you'd architect this product? What technologies would you use and why?"
• "What's your approach to performance optimization and monitoring?"
• "How do you handle database migrations in production?"
• "Tell me about a project where you had to scale a system. What challenges did you face?"
• "How do you approach security in your development process?"
• "What's your testing strategy? What coverage do you aim for?"
• "Show me an example of production code you've written. Walk me through it."
• "What's your approach to code reviews and quality assurance?"

Red Flags in Tech Stacks

• Outdated frameworks (using old versions from 5+ years ago)
• No testing strategy or automated testing
• Manual deployments without CI/CD
• Poor monitoring and no error tracking
• No version control or poor git practices
• Storing secrets in code or configuration files
• No database backups or disaster recovery plan
• Custom frameworks instead of industry-standard ones
• No documentation of architecture decisions

Next Steps

Ready to evaluate agencies? Follow this process:

1. Get your project brief ready (use our Brief Builder)
2. Identify 3-5 potential agencies
3. Use Tech Scanner to verify their tech stacks
4. Schedule technical deep-dives to discuss architecture
5. Review code samples and past projects
6. Compare their technical approaches
7. Make your decision based on both capability and cultural fit

See more in our guide on how to hire a dev agency.