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Tech StrategyMarch 18, 20266 min read

Build vs. Buy: How to Think About Internal Tools

The build vs. buy decision is one of the most consequential choices a growing business makes. Here's a framework for getting it right.

Every growing business eventually hits the same decision: do we buy software off the shelf, or do we build something custom?

It's one of the most consequential technology decisions a company makes — and most get it wrong, usually by defaulting to one answer without thinking clearly about the tradeoffs.

Here's a framework we use with clients to work through it.

Start with the question: is this a commodity function or a competitive differentiator?

If the problem you're solving is the same problem every business in your industry solves the same way, buy. Accounting, payroll, CRM, email — these are commodity functions. Off-the-shelf software exists precisely because the problem is universal and well-understood.

If the problem is specific to how your business operates — your unique workflow, your proprietary data model, your process that gives you an edge — build. No vendor builds software for your specific competitive advantage, because that's yours.

The hidden cost of buying

Software vendors love to show you the per-seat cost. They don't show you:

  • The hours your team spends working around the software's limitations
  • The cost of data that's locked in a system you don't control
  • The time lost to features you'll never use, cluttering the interface
  • The vendor dependency you've created — and what happens to your pricing when they know you're locked in

We've seen companies paying $50,000/year for enterprise software that a custom internal tool would have solved for a one-time $15,000 build and near-zero maintenance.

The hidden cost of building

Building isn't free either. Custom software requires:

  • Upfront design and development time
  • Ongoing maintenance when requirements change
  • Someone who understands the codebase well enough to modify it

The maintenance piece is where many custom builds fail. A tool built by a contractor with no documentation becomes a liability the moment that contractor leaves.

This is why documentation and knowledge transfer are non-negotiable for us in every engagement.

A simple decision matrix

BuyBuild
Generic problem✓ Strong choice✗ Likely over-engineered
Unique workflow✗ Constant workarounds✓ Strong choice
High volume / repetitiveCheck the API✓ Automation opportunity
Regulated dataCheck compliance✓ Control your own stack
Fast-changing requirements✗ Vendor lag✓ You control the roadmap

The often-overlooked middle ground: integrate

A third option that often gets missed: buy the commodity layer and build the glue.

Use Salesforce for CRM, QuickBooks for accounting — but build the custom pipeline that connects them, the dashboard that surfaces the right data, the automation that eliminates the manual steps between systems.

This hybrid approach often gives you the best of both worlds: proven software for the core functions, custom logic for the parts that differentiate you.


Getting it right

The worst build vs. buy decisions happen when the question gets answered by default rather than by design. "We've always used software for this" is not a strategy. Neither is "we'll just build it" without thinking through maintenance.

If you're at a decision point on internal tooling, we're happy to think through it with you. We have no stake in the outcome — we'll tell you to buy if that's the right answer.

Want advice for your specific situation?

Book a free 30-minute call. No pitch — just a real conversation about your business.

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