Comparison · 2026

Build vs Buy: A Framework for Software Decisions

Most build-vs-buy decisions are made on instinct. They shouldn't be. Here's the framework we use with clients when the answer isn't obvious.

Buy

Speed, predictable cost, vendor ops

Build

Fit, IP ownership, long-run economics

Side-by-side comparison

Axis	Buy	Build
Time to live	Days to weeks	Weeks to months
Capex risk	Low	Medium-high
Opex profile	Subscription, scales with users	Fixed hosting + maintenance
Competitive moat	None — everyone has it	Yours
Workflow fit	Forced to vendor's mental model	Designed around your operation
Compliance posture	Dependent on vendor	Controlled by you
Talent required	Operator	Engineering + operator

Pick Buy when

The problem is generic (calendar, email, payroll for standard staff)
You need it live this quarter
The vendor's solution covers 80%+ of your workflow
You don't have engineering capacity right now

Pick Build when

The problem is your competitive edge
SaaS at scale is more expensive than a build + maintain
Deep integration with proprietary systems matters
Vendor lock-in or compliance scope makes SaaS untenable

Our take

The decision framework: write down your top 5 must-have features, evaluate the top 3 SaaS options against them, then calculate 3-year TCO for each plus a custom build. If custom wins on TCO and the must-haves are not generic, build. Otherwise buy.

FAQ

What if we want both?

Common and reasonable. Buy SaaS for generic infrastructure (CRM, email, accounting). Build custom for the workflow that defines your business. Most of our clients run this hybrid.

How do you do the TCO calculation?

Project per-seat SaaS cost across 3 years at expected user growth, plus integration cost, plus migration cost. Compare against custom build + 20% / year maintenance. The break-even is often clearer than people expect.

When does building backfire?

When the problem is genuinely generic and the build only existed because someone wanted a vanity project. We've turned down build engagements where SaaS clearly won.

Still deciding?

Send us your scope — we'll come back in 24 hours with a written recommendation for the choice that fits your timeline, team and budget.

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