Juha Wilppu
In early 2017, I launched a side project called Siikli. It’s a simple, mission-critical ERP that has been used to invoice over €13M. (To clarify: That figure is the amount invoiced by my users, not my revenue.) How it started In 2016, a friend asked ...
Recently, I migrated our production servers from the US to Europe with zero downtime. The technical execution was straightforward with our plan, but caused one issue. Why we migrated We originally launched our servers in the US with high expectations...
Back in 2013, I tried to reinvent how kids learn math by building a competitive online multiplayer game. I tested it in a real classroom with 20 students. Here’s how it went. The idea I believed that competition would motivate students. Kids who norm...
IP whitelisting is old-school. But it’s also a simple way to add a surprisingly strong second layer of defence. Here’s how it saved us during a security audit. The mistake: Trusting the Host header We had a vulnerability in the “Forgot password” feat...
Many years ago, I lost production data that I couldn’t recover. I remember looking at the screen in disbelief. The mix of regret and helplessness is something I never want to experience again. Today, I use a “paranoid” backup strategy built on immuta...