Make Build or Buy Calls with Confidence in SaaS Products
Choosing between building, buying, or partnering for SaaS components can make or break a product strategy. This article breaks down six practical principles to guide these decisions, backed by insights from industry experts who have scaled successful SaaS businesses. These frameworks help teams avoid costly mistakes and move faster toward sustainable growth.
Own Security-Critical Components Internally
When deciding whether to build a capability in-house or adopt a third party, I use one clear rule: if the component affects security, compliance, or business continuity, treat it as a time‑sensitive in‑house responsibility or a tightly controlled migration. In practice, facing Elasticsearch 7 end of life taught us to treat such items as risk management efforts that require a proactive migration plan, like parallel sandboxes and reindexing budgets. We require cross‑functional ownership and explicit evidence for auditors and customers before accepting third‑party reliance. This rule gives us a repeatable way to prioritize internal control where the blast radius of failure is high.
Favor Seamless Integration over Feature Count
We don't make the build-versus-buy decision based on feature lists. We make it based on integration complexity. A third-party service might offer dozens of capabilities, but if it introduces more complexity, maintenance, or operational overhead than it removes, it's the wrong choice.
Our decision rule is simple - choose the option that keeps the overall product simpler and more reliable over the long term. Customers don't judge a platform by how many services sit behind it. They judge it by whether everything works together seamlessly, and that's the standard we rely on when making these decisions.
Enforce a 48-Hour Vendor Swap
Early on, I realized that adopting third-party tools for speed often resulted in catastrophic technical debt when that vendor inevitably raised prices or went offline. As a CTO, I now rely on the '48-Hour Portability' rule.
Before we adopt any third-party service for a foundational capability like authentication or payment processing, I ask the engineering team: If this vendor disappeared tomorrow, could we swap them out for a competitor within 48 hours? If the answer is no, it means the third-party tool requires too deep of an integration with our core architecture. In those cases, we either build the capability in-house, or we build a strict, custom abstraction layer in our codebase so our core application never directly talks to the vendor's API. This rule allows us to move fast with external tools without ever becoming a hostage to them.
Select Partners with Proven Consistency
I'll pay extra attention to a third party's reputation for consistency in these situations. If we're going to build our services on top of someone else's, we need to be sure we're working with someone who will still be around in a few years, who won't raise prices too often, and who will offer consistent support even for older products. This gives us a lot more predictability and reliability, which we can then pass on to our clients.
Prioritize Fast Reversible Paths to Revenue
I decide based on which option gives the shortest and most certain path to cash while keeping the risk reversible. My decision rule is to ask three questions: how quickly will this turn into cash, how confident am I that it will, and can we reverse it cheaply if we are wrong. If a third-party service helps us reach revenue faster with less uncertainty and an easy exit, we adopt it. If building in-house is the faster, more reliable route for our customers and we can unwind the choice without major cost, then we build it. Under tight cash, I prioritize speed and certainty first, because survival buys you the right to make bigger bets later.
Build What Customers Pay For
Bootstrapping two companies for 6+ years means every build-vs-buy call comes out of your own pocket, so you get clear on it fast.
The decision rule I kept coming back to: does this capability touch the thing customers actually pay for? If yes, build it. If no, buy it.
Early on with Pageloot we built our own QR code generation engine instead of using an API wrapper. Felt slow and expensive at the time. But QR code rendering, scan tracking, the analytics layer -- those are the product. If we'd outsourced that, we'd have been building on someone else's roadmap and explaining to Starbucks why we couldn't support a feature because our upstream vendor didn't.
The failure case was email delivery. We tried to manage our own sending infrastructure in year two. Thought we'd save money. What we actually got was a week of deliverability problems, churning a handful of users who thought the product was broken when it was really just our SPF records. Switched to a third-party provider, never touched it again.
So the rule became concrete: if a third-party goes down or changes pricing, does it break the customer's core experience or just cause internal pain? Internal pain is fine to outsource. Customer-facing fragility is not.
The edge case that trips people up is speed. Sometimes you buy a third-party service to validate that a capability is worth building at all. We've done that twice, where we used an off-the-shelf integration for 6-12 months, watched how customers actually used it, and only then rebuilt it properly in-house. Buying first doesn't mean buying forever. It means you're not building the wrong thing.
The trap is the opposite: building something foundational in-house because it feels strategic, when actually it's just infrastructure nobody sees. Authentication, billing, notifications -- buy those. Your core value loop -- build it yourself and protect it.
