Build vs buy: when SaaS is the right move

By Juan Martinez • Updated Feb 11, 2026

The simplest build vs buy framework

For each major part of your product, ask two questions:

• Is this core to our unique value? (your differentiation / IP)
• Would buying it reduce risk and speed up learning?

If it’s not core and buying helps you ship faster, you usually buy — at least for MVP.

Good candidates to buy (especially early)

These areas are often commodity and expensive to get right:

• Authentication (sign-in, password resets, MFA)
• Email delivery (transactional + notifications)
• Payments & billing (subscription logic, invoices, taxes)
• Analytics (events, funnels, dashboards)
• Search (unless search is your core product)
• Customer support tools (chat, tickets, knowledge base)

Good candidates to build

You typically build the parts where your company’s unique value lives:

• Your core workflows and business rules
• Your unique user experience and differentiating features
• Your domain-specific data model
• Anything that becomes strategic IP over time

What founders often get wrong

1) Buying something that becomes your core product

If your “secret sauce” becomes dependent on a vendor’s roadmap, you lose control. This isn’t always bad — but you should make that trade-off intentionally.

2) Building infrastructure too early

Building your own auth, billing, and messaging stack can easily consume months. That’s time you could spend validating demand, refining workflows, and learning from users.

3) Vendor lock-in without an exit plan

Buying is fine — but you should know how you could leave. Even a simple exit plan (data export, API boundary, abstraction layer) reduces risk dramatically.

A practical “buy now, build later” approach

This is often the best startup path:

• MVP: buy commodity services to move fast
• v1: stabilize and validate where you truly differentiate
• Scale: replace bought components only when they become limiting or expensive

How to evaluate a SaaS tool (fast)

• Speed: can you implement it in days, not weeks?
• Reliability: does it have a track record and good docs?
• Cost curve: what happens when usage grows 10x?
• Flexibility: can you adapt workflows, permissions, and data?
• Exit plan: can you export data and replace it later?

When you should build instead

Consider building when:

• The vendor limits a core workflow you must control
• The cost curve becomes unreasonable at your scale
• You need guarantees the vendor can’t provide (compliance, latency, data residency)
• Your product advantage depends on deep customization