Daniel Javier Costa

Overview

Currently at Radix Pay, where I lead iOS apps with a team of 28. Mentored 11 engineers through their first promotion. Reduced cloud spend on iOS by 32% in two quarters. Before that: Wise and Novo Nordisk. Most at home with Rust and UIKit.

Answers in batches on Fridays

Experience

1. CTO

   Jan 2025 - Present
   Radix Pay · 1 yr 9 mo · Full-time · Barcelona, Spain
   • Wrote the Rust service that now handles 29 million requests a day.
   • Cut p99 latency on the iOS services from 774ms to 93ms.
   • Shipped a rewrite that took build times from 32 minutes to under 5.
2. Principal Engineer

   Apr 2023 - Sep 2024
   Wise · 1 yr 5 mo · Full-time · Barcelona, Spain
   • Previously an operator for 8 years before investing.
   • Sit on 2 boards.
3. Senior iOS Engineer

   Feb 2021 - Apr 2023
   Novo Nordisk · 2 yr 2 mo · Full-time · Barcelona, Spain
   • Grew the iOS team from 5 to 30 engineers.
4. Senior Engineering Manager

   Jun 2018 - Feb 2021
   Société Générale · 2 yr 8 mo · Contract · Barcelona, Spain
   • Built the experimentation framework 11 product teams use to ship changes safely.
5. Senior iOS Engineer

   Aug 2014 - Jun 2018
   McKinsey & Company · 3 yr 10 mo · Full-time · Barcelona, Spain
   • Cut p99 latency on the iOS services from 357ms to 120ms.

Projects

No references yet.

Education

1. Bocconi University

   BSc, Computer Science
   2006 - 2009