Build vs Buy Software: An Honest Framework for Companies Under $10M
Let's be clear about what this article is, because the phrase trips people up. This is about build vs buy software: whether your company should write custom code for an internal tool or business system, or just license an existing product and pay the subscription. It is not about houses, and it is not about PCs. It is about the systems that run your operations, and the question is informational. You are here to make a decision, and we are going to give you a framework for it.
Here is the honest part most articles skip. The build-vs-buy debate is framed wrong. For a company under $10M, the real question is almost never "build or buy." The real question is: is this core? Buy the commodity stuff. Build only the rare wedge that is genuinely your competitive edge. And automate the glue in between on accounts you already own. Get that order right and the whole decision gets easier.
The Frame Everyone Gets Wrong
Most build-vs-buy advice treats it as a binary. Build the thing, or buy the thing. That framing was designed for enterprises with engineering teams to spare. You are not that company. You are a scaling founder, you are the bottleneck, and every hour your small team spends maintaining custom code is an hour not spent on product.
The better question splits your software into three buckets, not two. There is commodity software (everyone needs it, nobody wins on it). There is your wedge (the narrow thing you do differently from everyone else). And there is the glue between them (the connective automation that makes your bought tools talk to each other). Each bucket has a different right answer, and conflating them is how founders waste six figures.
The standard architecture heuristic backs this up: buy for commodity and build for differentiation, reserving custom code for the 10 to 20% of your product that truly sets the business apart (Neontri). Joel Spolsky put the underlying logic bluntly in his 2002 Strategy Letter V: "Smart companies try to commoditize their products' complements" (Joel on Software). Translation: do not pour engineering into the parts of your stack that are not your edge.
Why Building Commodity Software Goes Sideways
The case against building everything is not philosophical. It is in the data. McKinsey and the University of Oxford found that large IT projects run 45% over budget on average while delivering 56% less value than predicted (Runn). Only one in every 14 IT projects is delivered on time and on budget (Runn). The Standish Group's long-running CHAOS research has found that only about 31% of software projects are truly successful, while the rest are challenged or fail outright (Callibrity).
Those are the odds you take on when you decide to build a CRM instead of buying one. And the cost is not just the project. The U.S. Bureau of Labor Statistics put the median annual wage for software developers at $130,160 as of May 2024 (BLS), and that is base pay before benefits, taxes, and overhead push the loaded cost higher. Buying commodity software means somebody else carries that risk and that payroll. Meanwhile companies are already trimming what they own: BetterCloud's 2025 State of SaaS report found organizations use an average of 106 SaaS tools, down from 112 the year before, the second straight year of consolidation (BetterCloud). The trend is toward fewer, better-integrated tools, not more custom ones.
Build vs Buy vs Partner: A Side-by-Side Comparison
There is a third column most frameworks ignore. When the glue or the wedge does need building, your options are not just "hire a dev" or "buy SaaS." A fractional build partner is the path that gets you the build without a full-time hire or a six-figure agency project where you own nothing at the end.
| Factor | Build in-house | Buy SaaS | Fractional build partner |
|---|---|---|---|
| Best for | Your true competitive wedge | Commodity functions (CRM, billing, HR) | The glue and small custom wedges |
| Upfront cost | High (loaded dev salary) | Low (subscription) | Predictable retainer |
| Speed to value | Slow | Immediate | Fast |
| Who owns it | You | The vendor | You (built on your accounts) |
| Exit | Sunk cost | Cancel subscription | Cancel anytime, keep the work |
| Maintenance burden | Yours forever | Vendor's | Monitored for you |
The pattern across the scaling companies we have worked with is almost always the same shape. The bottleneck is not a missing custom platform. It is a dozen bought tools that do not talk to each other, and a founder doing the handoffs by hand at 11pm.
How to Make the Call in 4 Steps
Run any candidate tool or workflow through this before you write a line of code or sign a contract.
- Name the capability in one sentence. If you cannot, it is too vague to build.
- Ask the core test: would a competitor copying this hurt you? If yes, it might be your wedge. If no, it is commodity, so buy it.
- Check whether a mature product already does 80% of it. For CRM, billing, support, and HR, it always does. Buy and move on.
- For the remaining 20%, decide who builds the glue. A full-time hire is overkill for stitching tools together, and a fixed-scope agency leaves you owning nothing. A fractional partner building on your own accounts, staging first, is usually the right size.
Where the Glue Fits
This is the part the binary framing misses entirely. Most internal tooling at a scaling company is not a product. It is connective automation between SaaS tools you already pay for: move a closed deal from your CRM into onboarding, sync billing to your accounting system, alert the team when a key metric moves. That glue is real engineering, but it is not a build-an-app project. It is a connect-your-stack project, and it is a close cousin of broader internal tools work.
For that layer we recommend Make for visual multi-step scenarios, Zapier when you need the widest app library, and n8n when you want self-hosted control. The point is not the tool. The point is that the glue gets built and monitored on accounts you own, so you can cancel the partner and keep every scenario running. If you want the deeper how-to on standing this up, our piece on custom software development goes further on the build side.
Readiness Checklist Before You Decide
Run this checklist before you commit budget either way.
- You have written down which bucket the tool falls in: commodity, wedge, or glue.
- For anything "commodity," you have shortlisted at least two existing products to buy.
- For anything "build," you can state the competitive edge it protects in one sentence.
- You know who owns the accounts and code if a vendor or partner relationship ends.
- You have a staging-first plan so nothing touches production without approval.
- You have a rough loaded cost for the in-house option, not just the base salary.
Frequently Asked Questions
Should a company under $10M ever build software from scratch?
Rarely, and only for your wedge. If the capability is something a competitor copying it would genuinely hurt you, building can be worth it. For everything else, the failure odds and loaded payroll cost make buying the smarter call.
Isn't buying SaaS just renting forever with no ownership?
You do not own the vendor's product, true. But you also do not carry its maintenance, security, or roadmap. What you should own is the glue between your tools, built on your own accounts, so the connective layer stays yours even when individual subscriptions change.
How is a fractional build partner different from hiring an agency?
A traditional agency runs a fixed-scope project and often keeps the accounts and code. A fractional partner works inside your accounts on a predictable retainer, builds staging-first, and can be cancelled anytime while you keep everything that was built.
Do This Next
Pick one workflow that is eating your evenings and sort it into commodity, wedge, or glue before you spend a dollar. Buy the commodity piece this week from a proven vendor instead of scoping a build. Start the glue on your own accounts, staging first, so you keep control no matter who builds it. Choose a fractional partner over a full-time hire for the connective work, and keep your small team pointed at the product only you can build.