When to Build Custom vs Buy Off-the-Shelf

The question comes up repeatedly: should we build something custom or use an existing product? The answer is rarely obvious, and the wrong choice creates years of problems. This framework helps clarify when each approach makes sense.

The Appeal of Custom

Custom development promises exactly what you need, built exactly how you want it:

• Features tailored to your specific workflow
• No compromises to fit generic solutions
• Competitive advantage from unique capabilities
• Complete control over the roadmap
• No per-seat licensing fees

These benefits are real. For the right problems, custom development delivers tremendous value.

The Appeal of Off-the-Shelf

Existing products offer immediate capability with minimal effort:

• Ready now (no development time)
• Proven and tested by many users
• Ongoing updates and improvements included
• Support available
• Lower upfront cost
• Reduced risk—known quantity

For common needs, existing solutions are often the sensible choice.

When Custom Makes Sense

Core Competitive Advantage

If software is central to how you compete—if it's what makes you different—custom development may be essential. Using the same tools as everyone else rarely creates differentiation.

Examples: A logistics company's route optimisation system. A financial firm's proprietary analysis tools. An eCommerce business's unique recommendation engine.

Unusual Requirements

When your needs genuinely differ from the market, off-the-shelf solutions won't fit. Adapting yourself to generic software might distort operations or require expensive workarounds.

But verify requirements are genuinely unusual. Often, what feels unique is actually common—companies just haven't looked at how others solve similar problems.

Integration Needs

Complex integration between multiple systems sometimes requires custom development. When off-the-shelf products don't play nicely together, custom glue code or platforms become necessary.

Scale Requirements

At extreme scale, SaaS pricing can become prohibitive. Enterprise with thousands of users might find custom development cheaper over time than per-seat licensing.

Control and Security

Some industries require data control that SaaS can't provide. Regulatory requirements might mandate on-premises systems or specific security controls unavailable in standard products.

When Off-the-Shelf Makes Sense

Solved Problems

If your need is common, someone has probably built a good solution. Custom-building email marketing, CRM, accounting, or project management rarely makes sense—excellent products exist.

Don't build what you can buy unless buying genuinely doesn't work.

Non-Differentiating Functions

Internal tools that don't affect customers often don't need custom development. Your HR system, internal wiki, or expense tracking probably don't create competitive advantage.

Spend custom development budget where it creates value, not on back-office utilities.

Speed Matters

Custom development takes time—months or years. If you need capability immediately, an existing product (however imperfect) beats a perfect custom solution that won't exist for six months.

Limited Budget

Custom development is expensive. If budget is constrained, better to use good existing tools than build mediocre custom ones.

Evolving Requirements

If you don't yet know exactly what you need, custom development is risky. You might build the wrong thing. Starting with an existing product lets you learn requirements before committing to custom development.

The Hybrid Approach

It's rarely all-or-nothing. Common patterns include:

SaaS with Custom Integration

Use off-the-shelf products for individual functions, but build custom integration between them. You get proven products without being limited to their pre-built connections.

Platform Plus Custom Extensions

Start with a platform (Shopify, Salesforce, etc.) and add custom functionality where needed. The platform handles common requirements; custom code handles your specific needs.

Buy Then Build

Start with an existing product to learn what you actually need. Once requirements are clear, build custom solutions where the existing product falls short. This reduces the risk of building the wrong thing.

Questions to Ask

When evaluating build vs. buy:

1. Is this problem already solved well? Search thoroughly before assuming you need custom development.
2. Is this a differentiator? If it doesn't create competitive advantage, default to buying.
3. What's the total cost of ownership? Include development, maintenance, hosting, future development. SaaS subscriptions look expensive until you add up true custom costs.
4. What's the opportunity cost? Development resources spent on internal tools can't build customer-facing features.
5. Do we have the capability to build and maintain this? Custom software requires ongoing maintenance. Can you support it long-term?
6. What happens if we're wrong? Custom development is harder to reverse. SaaS can usually be replaced more easily.
7. How well do we understand our requirements? Uncertainty favours starting with existing products until needs clarify.

Common Mistakes

Custom because "we're unique": Most businesses are less unique than they believe. Generic solutions often fit 80-90% of needs.

Underestimating maintenance: Building is maybe 30% of total cost. Maintenance, updates, and improvements continue forever.

Not-invented-here syndrome: Preference for building everything internally, even when excellent solutions exist.

Ignoring opportunity cost: Resources spent building internal tools can't be spent on what actually differentiates your business.

Buying when custom is needed: Forcing a poor-fit product to work, spending more on workarounds than custom development would cost.

Our Approach

We're developers—we could advocate building everything custom. But we advise honestly: sometimes the right answer is a SaaS product, not hiring us.

When custom development genuinely makes sense, we build it well. When existing solutions fit, we help integrate and extend them appropriately.

If you're wrestling with a build vs. buy decision, contact us for an honest assessment of which approach fits your situation.