Contractbook - shipping what was actually needed

The Situation

After running my own R&D business with a pretty large team, I decided to try something different and join a small startup. But my karma was not ideal - the last backend engineer had already left by the time I joined. Sound familiar? He stayed long enough to walk me through the codebase and hand over the keys, and then I was on my own.

The good news: the codebase was solid. The bad news: it was all running on Heroku.

What I Shipped

I spent the first few days understanding the product, the business model, and what was actually blocking growth. Three things stood out immediately:

Self-service billing. The business was growing but couldn’t scale revenue without a proper billing system. I built one that let customers manage their own subscriptions, upgrades, and payments without needing sales or support to hand-hold them through it. The product was already really simple to use.

B2B API. Enterprise customers needed integrations. No API meant no enterprise deals. I built an API platform that opened that door.

CRM and marketing pipeline. The business team was flying blind - no proper data on user behavior, no way to track the funnel, no tooling to make informed decisions. I wired up the analytics and CRM integrations so they could actually see what was happening and act on it.

What I Learned

Sometimes a short engagement teaches you more than a long one. I was at Contractbook for about nine months, but it reinforced something I keep seeing: the biggest blocker to growth is rarely the code - it’s the missing pieces around it. Billing, APIs, data pipelines, infrastructure, ops and sales teams that can actually scale. The unglamorous stuff that lets a business go from “promising startup” to “real company” (they’re Series B now, with Microsoft as one of the investors).