Java Developer in Prague, Czech Republic
Consultant2011 - PRESENTFreelance
Technologies: Ruby on Rails, JRuby, TorqueBox, Trinidad, PostgreSQL, MySQL, Resque
- Helped a client resolve a concurrency issue on a high-load database connection.
- Provided on-site support for an application, expecting thousands of req/sec deployed to Heroku.
- Configured and fixed an application's ability to run with zero downtime deploys.
- Converted an outdated massive code base to an up-to-date Rails version (from 2.3).
- Resolved an issue in a TorqueBox/JBoss cluster for a client in staging, and offered advice for improving Server configuration.
Technical Support Engineer2016 - 2018Enrian
Technologies: Ruby on Rails, Tomcat, JRuby, Logstash, CircleCI, Apache JMeter, Splunk
- Started as a technical (support) expert for the team, dealing with production issues in one of Europe's biggest banks. This later also turned into implementing new features for the lending platform apps and pushing the technological stack for better tomorrows, while also helping out engineers in their day-to-day development.
Software Craftsman2008 - 2011JetMinds
Technologies: REST, Rails, JRuby, Trinidad, jQuery, Facebook Platform, J2ME, LWUIT, MySQL, Git, EC2, Puppet
- Built a social web application with a REST API for mobile clients.
- Invented a re-usable REST client for limited environments (J2ME) and built a portable mobile client using LWUIT.
- Automatized deployment and EC2 machine setup, using Puppet.
- Migrated the app to an early version of JRuby and performed routine maintenance, including fixes and implementing new features for the server.
- Became involved in open-source libraries and learned what open-sourcing a project entails.
JavaEE Consultant2009 - 2010Ceska Sporitelna, a.s.
Technologies: JaveEE, Beehive, WebLogic Server 10, WebLogic Portal 10, Oracle 10g, Maven, TeamCity
- Converted the existing (huge) infrastructure of a portal project, under Maven.
- Automatized build as much as possible, including generating setup files for a custom IDE.
- Helped the bootstrap of existing(internal) and new developers.
- "Hacked" a custom, third party application to run nicely on an existing infrastructure, since the new version was having issues with the logging libraries.
- Supported user requirements and adjusted third-party app to meet the needs of the bank's intranet.
Senior Developer2007 - 2008Tempest, a.s.
Technologies: JavaCard, Global Platform, Swing, AOP, PKI, JCE, LDAP, Groovy, Spring 2.x, MySQL, Sun Access Manager, Sun AppServer, Sun Portal Platform, Portlets, Sun Identity Manager
- Created a flexible, customizable and secure one-time-password solution, based on smart cards, from scratch.
- Built smart-card "hacking" tools to resolve an EMV-compatible communication protocol, with an OTP pocket-reader.
- Helped and managed a small team of junior and mid-senior developers.
- Developed an Identity module to integrate the company's user management software with Sun's Identity Manager.
- Built a few Nagios monitoring portlets for SysAdmins.
Software Engineer/Integration Consultant2006 - 2007Adastra, s.r.o.
Technologies: JavaEE, JSF, EJB, JDBC, JMS, WS, ESB, Spring, PL/SQL, Hibernate 3.x, JBoss 4.x, Oracle 10g
- Created a messaging layer to communicate with existing services over ESB.
- Crafted custom JSF UI components for the client side.
- Performed optimizations, by moving parts of the Java decision logic into PL/SQL.
- Built a support project for SQL migrations between releases.
- Built a project for reading FoxPro Database files seamlessly (in JDBC).
Team Leader2005 - 2006Dupres Consulting
Technologies: J2EE 1.4, EJB 2.1, Hibernate 3.0, RMI, MyFaces 1.1, JBoss 4.0, MySQL 5.0, Oracle 10g
- Built a domain model based on an existing design and requirements.
- Exposed a remote business-service layer for a front-end user interface.
- Developed a web prototype, which consumed the services and showcased design practices.
- Resolved back-end issues and lead its development with two others.
- Helped newcomers on both ends (back-end and front-end) to get into the work flow.
- JRuby (on Rails) (Development)https://github.com/jruby/
Worked on ActiveRecord-JDBC-Adapter, JRuby-Rack, Trinidad and much moret.
- Adtile (Development)http://www.adtile.me/
As ads met mobile, the API scales just right from the cloud.
- eVue (Development)
Make sure those industrial laundry machines keep working as they should.
- PeersONE (Development)
First social network that pushes you off-line ... low-cost and retro!
- INET (Development)
Portlets every where you look on the site of the largest bank in Czechia.
- CMS TatraBanka (Development)http://www.tatrabanka.sk
Collateral - collateral - collateral ... collateral management it is!
- MAIS (Development)
Facing some ~50.000 students daily as their central information system at the University, and still counting.
FrameworksRuby on Rails (RoR), Sinatra, Grails, Spring, JavaServer Faces
Libraries/APIsRhino, jQuery UI, jQuery, Node.js
ToolsApache Tomcat, Git
PlatformsJEE, Linux, TorqueBox, Oracle, Heroku, AWS EC2
StorageCache, MySQL, JBoss Cache, PostgreSQL, JBoss AS
- Master's degree in Mathematical Informatics2000 - 2005University of P.J.Safarik - East Coast