Essay · 10 min read

In Defense of Not-Invented-Here Syndrome

Joel Spolsky · Joel on Software Free Intermediate

This gives you the sharpest rule for the build versus buy call: if it is a core business function, build it yourself, and if it is not, buy it. Spolsky's line maps almost exactly onto the question you are asking, because auth, payments, and email are rarely the thing customers pay you for. Use it as a one sentence test you can apply to every piece of your MVP.

• Build the code that is your actual competitive edge, and only that
• Commodity functions bought off the shelf free you to ship the differentiated part faster
• The test is whether a function is core to why customers choose you