Pier Paolo Fumagalli, Developer in Berlin, Germany
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Pier Paolo Fumagalli

Verified Expert  in Engineering

Cryptography Developer

Berlin, Germany
Toptal Member Since
September 14, 2018

Pier is an experienced technology leader, passionate about all aspects of software: hardware and networking, from the server side, large-scale distributed architectures to small hardware prototypes. His experience stems from a solid background in open source having participated in the growth of Apache from a group of individuals into one of the biggest open source foundations, and as an advisor in numerous roles behind the Java platform.


Körber Digital GmbH (Berlin, Germany)
Distributed Systems, Java, JavaScript, Industrial Internet of Things (IIoT)
Relocately GmbH (Berlin, Germany)
Microservices, Salesforce, PostgreSQL, Angular, JavaScript, Node.js
Leomo, Inc. (Tokyo, Japan)
M4, ARM, STM32, Kotlin, Java, Linux, Android




Preferred Environment

Git, Eclipse, Sublime Text, Linux, MacOS

The most amazing...

...thing I've created was the Java EE platform and building the Apache Software Foundation from the ground up!

Work Experience

Lead Architect

2017 - PRESENT
Körber Digital GmbH (Berlin, Germany)
  • Joined Körber Digital, the digital arm of Körber AG, a world leader in the production of manufacturing machines, as their lead architect for smart factories.
  • Built a global platform collecting near-real-time telemetry data from industrial machines based on AWS IoT Core, and MQTT.
  • Designed and implemented a standalone gateway that was able to connect to a number of PLCs (Siemens S7, Allan Bradley, and others) and send MQTT messages over 4G/LTE connections based on Linux and Node.js; I built this to connect and extract data from industrial machines.
  • Developed a fully distributed, microservices-based architecture for the large-scale, globally distributed storage, analysis, and retrieval of time-series data, completely server-less on Amazon AWS.
  • Automated the build/test/release/deploy cycle for approximately 40+ individual microservices based on Git, CircleCI, and Ansible.
Technologies: Distributed Systems, Java, JavaScript, Industrial Internet of Things (IIoT)

Interim CTO

2016 - 2017
Relocately GmbH (Berlin, Germany)
  • Worked as the interim CTO of Relocately, a German startup that was innovating the way personal and corporate overseas relocations are handled.
  • Joined the Relocately co-founders in the early stages of the company and served as the interim CTO for the first six months until March 2016, then continued as technical and management consultant after successfully hiring their permanent CTO.
  • Outlined the initial vision and architecture for the technical platform and led the outsourced teams in charge with the first implementation, while at the same time building the initial in-house technical team.
  • Ensured that the platform was centered around SalesForce for both customer and partner management, and was augmented by several in-house external services dealing with the more specialized aspects of the relocation workflow (pricing, logistics, and inventory management).
Technologies: Microservices, Salesforce, PostgreSQL, Angular, JavaScript, Node.js


2015 - 2016
Leomo, Inc. (Tokyo, Japan)
  • Joined Leomo (a Japanese startup focusing on a hardware and software solution for professional cyclists) to structure the 20-strong technology team and introduce solid development practices; after the company's pivot from a software-only activity tracking app to a complex hardware and software solution.
  • Created the high-level organization of product development, project management, and development practices.
  • Drove the product re-architecture from two monolithic blocks (a Python/Django website and back-end, and a single on-device Android application) to a flexible, testable, separate set of microservices and applications/libraries.
  • Spent time learning in depth about the hardware development (especially custom Android devices, and low powered external sensors) and gathered some invaluable hands-on experience on Android internals and the STM32/ARM Cortex M4 hardware platform.
Technologies: M4, ARM, STM32, Kotlin, Java, Linux, Android

Engineering Manager

2015 - 2015
Groupon (Tokyo, Japan)
  • Joined Groupon as a consultant to provide help and guidance to the local Tokyo team during their migration of the Japanese-specific site and infrastructure onto Groupon's global infrastructure platform.
  • Coordinated the platform and data migration from a monolithic PHP codebase to Groupon's international microservices based platform.
  • Trained the local team on the new architecture and coding practices.
Technologies: Java, Node.js, PHP

Founder | Owner

2013 - 2014
USRZ.com (Tokyo, Japan)
  • Spent approximately one year consulting with smaller startups and more established companies approaching the complex task of building high-profile technology teams in Japan.
  • Worked on a few projects that were focused on applied cryptography, specifically trying to address the problems of user, directory, and single-sign-on management across web, devices, and connected services (e.g., SSH) for small-to-medium enterprises.
Technologies: Cryptography, Java, Node.js


2010 - 2013
Gilt Groupe (Tokyo, Japan)
  • Joined Gilt Groupe Japan in order to build and lead the technology team in Tokyo.
  • Grew the team grew from three people to more than 20 developers and QA engineers, while we shifted the focus from primarily translating and customizing our US-developed platform to a locally-led and developed system, better answering the demands of the Japanese business.
  • Re-engineered the main eCommerce website and moved from a monolithic Ruby on Rails system to a multitiered microservices architecture employing Java and Node.js REST back-end services communicating with a fully responsive Angular front-end.
  • Focused on optimizing our hardware investment through the use of Linux and Linux containers, achieving dynamic optimization of hardware resources through pseudo-virtualization and automated deployments, and using third-party services such as Amazon's EC2 and S3 when needed.
  • Achieved a better synergy with local partners, especially on the logistics front where we completed the integration with two different Japanese 3PL/WMS solutions for our local warehouses, and on the payment front as we integrated with Japanese credit card providers and local payment methods such as convenience store payments.
  • Was directly involved in a more hands-on role, leading the engineering effort behind the main CRM platform overseeing user analysis, segmentation, targeting, and email personalization and delivery.
Technologies: LXC, Linux, Ruby, PostgreSQL, Angular, Node.js, JavaScript, Java

Reliability Architect

2010 - 2010
Ning (Palo Alto, United States)
  • Architected and implemented a prototype for a large-scale distributed cloud management infrastructure solution based on Linux containers managed via RESTful services. The resulting platform resembled what today can be achieved with Docker and Kubernetes, from container management to services orchestration.
  • Developed a product was designed to manage and optimize the deployment, monitoring, configuration and usage of Ning's internal software on a pool of 1,500+ physical servers and approximately 5,000 virtual machines.
Technologies: Java, LXC, Linux

Senior Architect | Tech Lead

2006 - 2009
Joost (New York, United States)
  • Primarily worked on the architecture of the back-end platforms for Joost, a startup company focusing on delivering video over the internet.
  • Dedicated most of my time ensuring that our metadata and event collection services could be scaled horizontally in order to cope with traffic demands and could be made fault tolerant.
  • Manage a small New York-based team of five back-end engineers, and during this phase, I was given the responsibility of leading the architecture and re-implementation of our web platform.
  • Built a new web architecture that was based on a set of autonomous RESTful services, fronted by a custom server-side publishing framework written in Java, and uses the Rhino JavaScript engine as a logic controller and Apache Velocity for view rendering.
Technologies: JavaScript, PostgreSQL, Linux, Java


1997 - 2009
Apache Software Foundation
  • Joined the Apache Group in 1997 as one the main contributors behind Apache JServ, the very first open source Java servlet container.
  • Helped outline the path behind Sun's donation of the Java Servlet Development Kit (what later became Apache Tomcat), and contributed in the definition of the underlying initial structure of the Foundation.
  • Aided in the creation of the Apache XML Project.
  • Co-founded the Apache Jakarta Project.
  • Contributed to a number of Apache and non-Apache open source projects (Tomcat, Cocoon, HTTPD, JDom, Jetty, and several others).
  • Participated in different standardization efforts: I was a member of the expert group of the Java Servlet and JSP specifications (JSR 53, 154 and 315), XML (JSR 5 and 63) and of the overall J2SE 5.0 specification (JSR 176).
Technologies: XML, Java

Principal Architect

2002 - 2006
VNU Business Publications (London, United Kingdom)
  • Joined VNU (now Incisive Media), one of the biggest B2B publishing companies in Europe, in early 2002 initially as a senior developer and technical lead.
  • Led a small team of Java and XML engineers and focused on a number of different projects.
  • Developed VNU's subscriber information database, a unique database collecting demographic data across on-line users and print subscribers.
  • Created VNU's web presence: focusing on a cost-effective, open-source based (MySQL, Linux, Apache, Java, Cocoon/XML) replacement of a number of proprietary and extremely expensive systems (mainly Oracle, Sun).
  • Constructed VNU's news workflow: the complete back-office re-architecture, integrating the new website's back-end with a new content management system (Hippo), a taxonomy-based knowledge and search engine (Autonomy), Quark DMS (digital asset management and off-line publications), and others.
  • Began working on VNU's pan-European architecture and the platform (which my team and I designed for the UK) and scaled it to power the other six European countries where VNU was present.
Technologies: XML, Solaris, Linux, Oracle, Java

Senior J2EE Developer

2000 - 2001
Sun Microsystems (Sunnyvale, United States)
  • Joined Sun's J2EE development team in August 2000 where my primary task was to work on the Servlet API reference implementation: Apache Tomcat.
  • Participated in a number of JSRs including the Servlet and JSP, XML Processing, and Java Daemon specifications.
Technologies: XML, Jakarta EE, Java

The Apache Software Foundation

I was one of the co-founders of the Apache Software Foundation and saw it grow from a small group of friends, into one of the biggest open-source organizations on the planet.

I am happy to have been a member from the very first day of the Foundation's existence for more than a decade and to have been a part of shaping its community, serving on the PMC of several projects, and as a guide for new members, developers, and projects.

Leomo Type-R

At Leomo, I led the development of both software and hardware of the Type-R motion analysis system for the professional cyclist.

Today, the same product I put so much love and passion into, is also used by Cameron Wurfone–one of the top triathletes in the world–to monitor and improve his training.

Apache Tomcat

I started working with Java Servlets, the core Java API for HTTP servers, in 1997 while developing the very first open-source engine Apache JServ.

Throughout the years, I've contributed both to the development of Tomcat, the servlet reference implementation, and the Java Servlet specification itself; acting as a core member of the specification team for more than a decade.


Rodosha is a library to allow multithreaded JavaScript programming in the browser.

Before the WebCrypto API came along, implementing cryptography in the browser resulted in long pauses in the main thread, application freezes.

The solution I found was to implement multithreading, in pure JavaScript, with a little bit of help from web workers.

Guice for Android

While working for Leomo, we wanted to use proper dependency injection (JSR-330 style) within our applications.

My port of Guice for Android allows not only the use of simple @Inject annotations but integrates perfectly with the lifecycle of Android apps and services.

TestNG for Android

While at Leomo, I wrote the de-facto standard port of TestNG (the best Java unit testing framework available) for Android platforms.


Node.js, Java Servlets, Salesforce API


Git, CircleCI, Ansible, IntelliJ IDEA, Sublime Text


Swagger, Google Guice, Express.js, Angular


JavaScript 6, Java 8, Python 2, C, JavaScript, Java, Kotlin, M4, PHP, Ruby, XML


Agile, Concurrent Programming, Microservices


Linux, Android, Debian, Ubuntu, Amazon EC2, AWS IoT Core, AWS Lambda, Eclipse, MacOS, STM32, Oracle, Solaris, Jakarta EE, Salesforce


PostgreSQL, JSON, MongoDB


Cryptography, SSL Certificates, SSL, Industrial Internet of Things (IIoT), Distributed Systems, ARM, LXC

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