Sr. Software Engineer @ Marqeta is an online-to-offline payments and commerce platform that gives consumers more money for the things they buy everyday, enables merchants to capture repeat business and greater customer spend and empowers large enterprises to better serve their constituents by participating in the payment stream of relevant transactions. It's the most
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Sr. Software Engineer @ Marqeta is an online-to-offline payments and commerce platform that gives consumers more money for the things they buy everyday, enables merchants to capture repeat business and greater customer spend and empowers large enterprises to better serve their constituents by participating in the payment stream of relevant transactions. It's the most advanced card payment platform ever built. From November 2014 to Present (1 year 2 months) Infrastructure Engineer (Sr. Software Engineer) - Socialcast @ Member of the Socialcast On-Premise team. Socialcast is a social network for the enterprise and way better than email. I split my time between three primary areas of focus.
First, I worked on building and configuring the virtual appliance that we shipped to our on premise customers. I helped maintain an appliance that was based on CentOS and Puppet.
Second, I maintained a Rails application which allowed customers to easily configure and deploy their cluster. I added a number of features at this point as well as fixing a few minor bugs. It was a solid codebase built by some very awesome senior colleagues of mine.
Third, I assisted customers with upgrade, install, and troubleshooting. This meant getting on a phone call or WebEx to talk to the people who were actually running and using our software. I dealt with customers on either coast in the USA as well as customers based in Europe. I did support calls that were as short as 30 minutes and as long as 12 hours. Multi-day engagements with customers and external vendors also occurred. From February 2012 to November 2014 (2 years 10 months) Site Engineer @ My primary focus was helping the Core Services team scale out a new backend infrastructure for serving ads. We had 1M+ mobile clients in the wild but we served it without issue through judicious use of caches and CDN.
I worked on interesting one-offs: I got to write a data pipe using ZeroMQ to funnel lots of email demographic data from our Social data warehouse into a legacy email system for targeted marketing.
I supported PlayFirst's old website. I tried not to write too much new J2EE code, preferring to inject Spring under the hood to make certain tasks easier. I used Quartz to circumvent a home-grown scheduling implementation. I also helped make the site stable by tweaking some Java memory settings - the site was regularly hiccuping from GC issues before then.
I also maintained some Python scripts that pulled in data feeds from portal partners to update prices on the main website. From January 2011 to February 2012 (1 year 2 months) Software Engineer @ Member of Foundational Services Team. Worked on CafePress's backend SOA infrastructure to help keep the site stable and performant. Got to pair with some really awesome people who taught me a ton.
Primarily worked in C#/.Net and Java 6. On the Java side, we used Spring, Maven, Jersey and JUnit as a framework for building services. On the C# side, the team used NHibernate, NUnit, Spring.NET and NAnt to modernize the legacy codebase.
A major project involved migrating 6M+ rows of customer credit card data from one data store to another, securely and transparently, as part of a PCI compliance effort. The project was completed without any customer impact. We also built into the software a "contingency plan" for high availability and failover. From August 2009 to December 2010 (1 year 5 months) Infrastructure Engineer @ Member of the Developer Operations team. Helped build and administer infrastructure to assist in the development and deployment of new code.
The bulk of my time was spent supporting our VMware-based Dev lab. Our lab had 150+ virtual machines so I helped automate the process of setting up new environments using Ruby. I also helped troubleshoot network and performance issues, sometimes working closely with VMware support to help get our issues resolved.
I also helped administer our Perforce server. From May 2008 to August 2009 (1 year 4 months) QA Engineer @ Wrote a great deal of UI automation using Gosu, Guidewire's then-proprietary, now open-sourced, programming language.
Also automated a few test areas with Ruby.
Learned Gosu and the scripting framework well enough to be able to give a small introductory lesson to the Demo team.
When our internal QA build tool was being re-written, I wrote some Windows automation scripts to turn the developer build and deploy process into a one-click process for the QA engineers. The automation was flexible enough to be re-used across different teams. From 2006 to 2008 (2 years)
B.A, Economics @ University of California, Santa Cruz Sebastian Wittenkamp is skilled in: Ruby, Agile Methodologies, REST, Java, Linux, Ruby on Rails, Perforce, Bash, Git, Spring, Software Development, Web Applications, Python, Cloud Computing, JUnit
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