Systems design for Advanced Beginners

You’ve started yet another company with your good friend, Steve Steveington. It’s an online marketplace where people can buy and sell things and where no one asks too many questions. It’s basically a rip-off of Craigslist, but with Steve’s name instead of Craig’s.

You’re going to be responsible for building the entire Steveslist technical platform, including all of its websites, mobile apps, databases, and other infrastructure. You’re excited, but also very nervous. You figure that you can probably cobble together a small website, since you’ve done that a few times before as part of your previous entertaining-if-morally-questionable escapades with the Stevester. But you have no idea how to even start building out all of the other infrastructure and tools that you assume lie behind large, successful online platforms.

You are in desperate need of a detailed yet concise overview of how real companies do this. How do they store their data? How do their different applications talk to each other? How do they scale their systems to work for millions of users? How do they keep them secure? How do they make sure nothing goes wrong? What are APIs, webhooks and client libraries, when you really get down to it?


You send a quick WhatsApp to your other good friend, Kate Kateberry, to see if she can help. You’ve worked together very effectively in the past, and she has decades of experience creating these types of systems at Silicon Valley’s biggest and most controversial companies.

She instantly accepts your job offer. You had actually only been ringing for some rough guidance and a good gossip, but you nonetheless instantly accept her acceptance. No point looking a gift horse in the mouth, even when you don’t have any money to pay her. Kate proposes that her first day be 5 weeks ago in order to help her smooth over some accounting irregularities. She can come into the office sometime next week. You feel encouraged and threatened by her eagerness.


Kate bounces into your offices in the 19th Century Literature section of the San Francisco Public Library. “OK let’s do this!” she shouts quietly. “What have we got so far? How are all our systems set up? What’s the plan?” You lean back in your chair and close your laptop, which was not turned on because you have left your charger at home. You steeple your fingers in a manner that you hope can be described as “thoughtful”.

“Let me flip that question around, Kate. What do you think the plan should be?”

Kate takes a deep breath and paints an extremely detailed vision of the Steveslist platform five years into the future and the infrastructure that will power it.


Read Kate’s in-depth vision in full on my blog. It’s long and detailed and covers topics from database to webhooks, and by the end you’ll understand the infrastructure behind almost all modern online companies.

Read it now.

Rob