Build vs. Buy vs. Integrate: A framework for technology decisions

You need a new system. Maybe it's a CRM. Maybe it's inventory management. Maybe it's a customer portal or an internal workflow tool.

Someone suggests building it from scratch. Someone else points to a SaaS product that does something similar. A third voice suggests connecting the tools you already have.

Everyone has an opinion. No one has a framework.

This is one of the most consequential decisions you'll make — and one of the easiest to get wrong. Build the wrong thing and you've wasted hundreds of thousands of dollars. Buy the wrong tool and you'll spend years working around its limitations. Integrate poorly and you'll have a Frankenstein system that nobody trusts.

So let's fix that. Here's a practical framework for making build-vs-buy-vs-integrate decisions that you can use starting today.

The three options, explained simply

Before diving into when to use each, let's be clear about what we mean.

Build means custom software development. You're creating something that doesn't exist — designed specifically for your business, your workflows, your requirements. It's yours. You control it completely.

Buy means purchasing existing software, usually SaaS (Software as a Service). Salesforce. HubSpot. QuickBooks. Tools built for the general market that you configure to your needs.

Integrate means connecting your existing tools to work together. Your CRM talks to your accounting system. Your website feeds into your ERP. Data flows automatically between systems you already own.

Each approach has its place. The question is: which one is right for this specific decision?

The decision criteria

Here's the framework we use with clients. For any technology need, evaluate these five factors:

1. Uniqueness: Is this a source of competitive advantage?

This is the first and most important question.

If the capability you need is genuinely unique to your business — something that differentiates you from competitors — custom development often makes sense. Your proprietary pricing algorithm. Your unique customer matching system. Your specialized manufacturing workflow.

If the capability is table stakes — something every business in your industry needs — you're usually better off buying. There's no competitive advantage in having a slightly better invoicing system or a marginally faster expense reporting tool.

The test: Would a competitor benefit from having this exact system? If yes, you probably don't need to build it.

2. Availability: Does a good solution already exist?

Sometimes the decision is made for you.

If there's no commercial product that does what you need, building is your only option. But be honest with yourself here. "No product does exactly what we want" is different from "no product does what we actually need."

Most SaaS products cover 80% of requirements. The question is whether the missing 20% is truly essential or just nice-to-have.

The test: Have you actually evaluated existing products, or are you assuming they won't work?

3. Flexibility requirements: How much will this need to change?

SaaS products are designed for the general market. They evolve according to the vendor's roadmap, not your wishlist.

If your requirements are likely to change frequently, or if you need the ability to adapt quickly to market conditions, custom software gives you control. You decide what gets built and when.

If your needs are relatively stable and the product category is mature, SaaS flexibility is usually sufficient.

The test: How much customization have you needed in similar tools over the past five years?

4. Total cost: What's the real long-term expense?

This is where most companies make mistakes. They compare the wrong numbers.

SaaS appears cheap — $50/user/month sounds trivial. But multiply by users, multiply by years, add the cost of integrations, add the productivity lost to workarounds, add the cost of switching when you outgrow it.

Custom development appears expensive — $200K for a system sounds daunting. But there are no per-user fees. No forced upgrades. No dependency on a vendor's survival. And you own it forever.

Neither is inherently cheaper. The math depends on your specific situation.

The test: What's the five-year total cost of ownership for each option, including all hidden costs?

5. Time sensitivity: How fast do you need this?

SaaS wins on speed. Sign up today, configure tomorrow, go live next week.

Custom development takes months, sometimes longer. If you need something immediately, building probably isn't realistic.

But beware of "we need it now" urgency that leads to buying the wrong tool. A slightly delayed right decision beats a fast wrong one.

The test: What's driving the timeline? Real business constraints or just impatience?

The common mistakes

We see the same errors repeatedly. Here's what to avoid:

Mistake #1: Building commodity features

You don't need a custom invoicing system. You don't need a custom email platform. You don't need a custom authentication system.

These are solved problems. Billions of dollars have been spent making these tools reliable and feature-rich. Your custom version won't be better, and building it means not spending that time on things that actually differentiate your business.

The principle: Build only what's truly unique. Buy everything else.

Mistake #2: Buying inflexible tools for core operations

The flip side: buying a rigid SaaS tool for something at the heart of how your business operates.

We've seen companies try to run their entire manufacturing operation on a $50/month project management tool. It sort of works — until it doesn't. Then they've got years of data locked in a system they've outgrown, and switching is a nightmare.

The principle: The more central to your operations, the more flexibility you need.

Mistake #3: Underestimating integration complexity

"We'll just connect our systems" sounds simple. It rarely is.

Integration projects routinely take 2-3x longer than expected. Data doesn't match cleanly between systems. Edge cases multiply. What started as "just sync the customer data" becomes a six-month project.

This doesn't mean integration is the wrong choice — often it's exactly right. But budget appropriately.

The principle: Integration is a real project, not a configuration task.

Mistake #4: Ignoring maintenance and evolution

Custom software doesn't maintain itself. Technologies change. Security patches are needed. Your business evolves and the software needs to evolve with it.

If you build something and don't budget for ongoing development, you'll end up with a legacy system that nobody wants to touch.

The principle: Custom development is a commitment, not a one-time purchase.

Mistake #5: Assuming "best of breed" means best results

Having 47 specialized tools that are each "best in class" sounds impressive. In practice, it usually means:

• 47 logins
• 47 data silos
• 47 potential integration points
• 47 vendors to manage
• No single source of truth

Sometimes a less specialized tool that integrates well is the better choice.

The principle: System coherence often matters more than feature richness.

The decision matrix

Here's a simple framework you can use. For each technology need, score these factors 1-5:

Total score:

• 5-10: Lean toward buying existing SaaS
• 11-17: Consider integration or hybrid approach
• 18-25: Custom development likely makes sense

This isn't a formula — it's a starting point for the conversation. The factors aren't equally weighted, and context matters enormously.

Real examples

When building made sense: A distribution company needed to manage complex customer-specific pricing with thousands of rules that varied by relationship history, volume, season, and competitive positioning. No off-the-shelf system could handle the complexity. Custom development was the clear choice.

When buying made sense: A professional services firm needed expense tracking and reimbursement. Nothing unique about their requirements. They bought Expensify and moved on. The decision took an hour.

When integrating made sense: A retailer had invested heavily in both Shopify and NetSuite. Neither was going anywhere. Instead of replacing either, they built custom integration that kept inventory and orders in sync. Each system does what it does best.

When the wrong choice was made: A manufacturing company built a custom CRM because they didn't like Salesforce's interface. Three years and $400K later, they were still missing features that Salesforce had out of the box, and they'd spent most of their development budget on non-differentiated work.

Making the decision

When you're facing a build-vs-buy-vs-integrate decision:

1. Start with the problem, not the solution. What capability do you actually need? What business outcome are you trying to achieve?

2. Evaluate honestly. Have you actually looked at existing products? Have you actually scoped what building would require?

3. Consider hybrid approaches. Sometimes the answer is "buy a base system and customize it" or "build the core but integrate commodity features."

4. Get outside perspective. Internal teams have biases. Developers want to build. Executives who bought a tool want to justify it. Someone without those biases can see more clearly.

5. Plan for the long term. The right decision for year one might not be the right decision for year five. Think ahead.

Where Entvas comes in

This is exactly what we help clients think through.

We're not a dev shop trying to sell you a custom project. We're not a SaaS vendor trying to sell you licenses. We're a technology partner trying to help you make the right decision — which sometimes means building, sometimes means buying, and sometimes means integrating what you already have.

If you're facing a technology decision and want a clear-eyed perspective, let's talk. We'll help you figure out which approach actually fits your situation.

Entvas Editorial Team

Helping businesses make informed decisions