DatabaseElasticsearch MongoDB Redis MySQL Lucene DB2/2 Informix Oracle OpenLDAP PostgreSQL HsqlDB H2
Web-ServerLighttpd Nginx Apache Http Tomcat JBoss Bea Weblogic Coucho Resin James JetSpeed
FrontendHTML CSS / LESS / SASS React Vue / Nuxt Svelte / Sapper Pure.css / Bootstrap, Bulma, RMWC Mithril Knockout Gimp Inkscape
Build ManagementAnt Atmosphere Brunch Gulp Gradle Maven make npm Rollup
Version ManagementGit Mercurial Subversion CVS
TestMocha Chai Cheerio jUnit Gatling Selenium
FrameworkAspectJ Cocoon FOP Grails Hibernate iText JavaCC JUnit Log4J Meteor Mithril React React Native Spring Struts Swing XStream
StandardAOP EJB J2E JAAS JDBC JMS JNDI JSP Servlet OMT OOD OOP RUP Scrum SOAP SQL UML V-Modell XML XP XSLT XSL:FO
Planning/DocumentationConfluence Daisy JIRA Liferay MS Project OpenOffice TRAC Trello Enterprise Architect
OSLINUX OS X Solaris Windows
Side project initially written for a family business to rent out properties in Paraguay. Currently working on a MVP for international markets.
Recruiting platform based on a video interview process
In-house web app for all business processes of a management consultant company. The app includes the external website and modules for clients, consultants and different company administrators.
User can write Stori(es) and share them with selected contacts. The MVP has extended image editing features, runs on iOS and in the browser.
Backend Developer, CTO, Tutor.chat, Homework.chat2016-05 — 2016-10 | CoffeeScript Meteor MongoDB Redis Git Google Analytics IBM Watson Segment Mixpanel Sendgrid Twilio
Tutors are able to give chat based private lessons on the subjects maths, physics, chemistry and biology. The clients connect with iOS or Android devices. I started working on the back end for the mobile applications and the tutor front end, as the company grew took over the role of a CTO hiring and coordinating a team in 9 different countries travelling between Barcelona and Asunción.
Developer, WorkGrades2016-04 — 2016-05 | CoffeeScript Meteor MongoDB Git Google Analytics Hotjar
WorkGrades takes the guesswork out of checking references. We’ve made it easy for candidates to reach out to past employers, verify their work history, and rack up recommendations.
Tech lead, Sales Booster2015-11 — 2016-03 | CoffeeScript Meteor MongoDB Git Trello Slack
Salespersons find used cars somewhere in the USA. Salespersons save searches
and receive an email once new results arrive. Salespersons choose listings
and send them per email or text message to potential buyers.
Developed from prototype to production and still do the hosting
Marketing application based on surveys.
Developing new features and maintained the site for a San Francisco Start Up.
Game to teach math
Students: Do your exams or homework or just play against the machine or other students, win coins, trade coins for prizes.
Teachers: Define questions and exams. assign them to classes or individual students, use extensive reporting features.
Tech lead, Rsrvtr2015-09 — 2015-10 | CoffeeScript Meteor MongoDB moment.js Git SOAP
Customer-Notification-System: Question the reservation system of a limousine
service through a SOAP API, correct time zone data and display them.
User: Send or schedule text messages (sms) to clients.
Administrator: Define text message templates
Creator, Protothril2015-05 — 2015-08 | CoffeeScript Cordova Elasticsearch Express Git Gulp Node
Application blueprint. A little bit like Meteor but based on Mithril and Elasticsearch.
Creator, meteor-accounts-t9n2014-02 — Present | CoffeeScript Meteor Git
Beside a solid translation engine it comes with more than 30 translations for Meteor standard modules, it has over 50 contributors and more than 6.000 downloads on Atmosphere
Developer, Ganagro2014-02 — 2014-12 | CoffeeScript Meteor Mercurial MongoDB
Planing and Administration for Cattle Farming
Acquisition, Sales, Breeding, Insemination, Vaccination, Diet, Statistics, Rainfall, Bookkeeping
Financing, Tenancy of Animals and Ground
Developer, Prestafin2013-11 — 2014-01 | CoffeeScript Meteor Git MongoDB
The client offers financing of consumer credits to retail stores. The retailer uses his computer or mobile phone to consult the credit line of the customer which gets reported back to him after a short research by the credit agents on his display and by email. The retailer then is able to generate and print a contract that the customer signs. The systems offers various statistics and reports.
Consultant, Chaco2013-03 — 2013-09 | Groovy MySQL Eclipse Libnotify Gradle MySQL Restlet Centos MCDM (Decision Making)
A leading paraguayan money exchange company grows quickly (about 400 employees now and growing by 30%/year) and wants a system check for all its information systems and an actionable catalog of projects to execute to guarantee this growth rate. Side goals are to asure that the systems can be extended to integrate franchising partners in the future and to extend the business model to neighbour countries.
- Analisis of the system landscape in the central and the branches, Interviews with all responsible staff and partner companies
- Creation of a catalog difining 17 follow up projects
- Development of a MySQL replication that reduces the time to consolidate the data between 30 branches and the central to a few seconds instead of 20 minutes
- Market-Study about money exchange software that works with virtual currencies and mobile devices and has an easy migration path from the systems in production today.
- Search-Engine for paraguayan tax numbers (http://ruc.sun.com.py/) - (Scala/Xitrum/Lucene)
- Search-Engine for Clasified Ads in Paraguay (http://agrupados.biz/) - (Scala/Lucene)
- Web Shops Platform (http://shops.com.py/) - Example Shop, (Java/MongoDB)
- Clasified Ads (http://ads.sun.com.py/) - (Java/H2)
- Several Play Framework Modules (https://bitbucket.org/softwarerero)
Developer, architect, technical project lead, consultant, Lots of projects mainly with Java, Smalltalk and C++1991-08 — 2010-10
Managing Director, SUNCOM Systems2004-02 — 2016-12 | Freelancing
Development consulting most of the time as a one-person-company, sometimes with other freelancers under the company umbrella. Releasing a bunch of web applications under the brand SUNCOM Systems.
Lead Consultant, Unilog (Logica)2002-01 — 2004-01 | E-Business Project Leading Project Planning Budgetting Sales Support Offer Strategy Conference Speaking
Representing the office in Stuttgart in the area of E-Business. Coordination and development of several Java projects
Developer, Architect, Technical project lead, Freelancing1994-01 — 2003-12 | Smalltalk C++ Java
Consultant for object oriented software development, Ingenieurbüro Letters1991-08 — 1993-12 | Smalltalk C++
After leading the support team for 6 month the first consulting experience coaching clients on site and working on their projects with Clipper, C++ and Smalltalk
- Distributed sales support system working offline and synchronizing data as soon as a network is available
- Programable Workflow-System for 6.000 public workers in Switzerland
Diplom-Informatiker (Computer Science), Freie Universität Teufen1997-10 — 2000-01
Thesis: A distributed and secure development environment based on open-source components.
Studies of computer science
3 semester of business administration
Introduction to ViewModel, MeteorBCN #6, June 20162016
Stefan will talk about ViewModel, a view layer that integrates with Blaze. While there has been much discussion if one should use React, Angular or Vue, other technologies haven't got much attention, sometimes the discussion feels politically motivated. ViewModel solves a lot of the problems people face with Blaze, it is easy to use and helps to write less code. It can bring back the fun to Blaze development. The presentation can be found here.
Nicholas Hinrichsen, Founder of Carlypso Inc (Y Combinator)
I asked Stefan to create a prototype car search interface for our sales team. Two days later he came up with an impressing demonstration. Then we asked him to build Sales Booster, the new central sales application of Carlypso. He understood what we needed and build it in record time. Whenever we come up with new ideas it usually pops up in staging or production a few hours later as he does our hosting too.
Jordan Baker, Founder of Scyent
We were looking for a Meteor developer to integrate quickly a bunch of features into a math game. Stefan connected right away with our globally distributed team, grabbed tickets from our Scrum board on Trello and implemented them in record time. He came up with creative ideas and thought out of the box for the better of our product. We look forward to work with him in the future.
Silviu Bojica, Lead developer at +1 Math, peer developer at Tributr
Silviu is based in Dubai, he can be reached under his office number +1-650-842-0703. Our team was distributed over San Francisco, Dubai, Asunción and we communicated mainly with Slack, Skype and Trello.
John Wentworth, Data Scientist at Carlypso Inc
John is responsible at Carlypso's San Francisco office to squeeze the most data out of Salesbooster. You can reach John at email@example.com.
Editor2014-07 — 2016-05
Activity: Editing a German online newspaper with daily information about Paraguay
Details: On a normal day we have around 5.000 to 6.000 page views. According to the German embassy Paraguay has a community of about 100.000 to 120.000 German speakers.
German Teaching2015-02 — 2015-06
Activity: Substitution teacher for a semester
Location: Universidad Paraguayo Alemana, San Lorenzo
Activity: Teaching a sunday school group, leading (together with my wife) the weekly prayer group, preaching
Location: Iglesia Cristiana Bautista Villa Patricia
Creating Websites1998-01 — Present
Activity: Creating dozens of websites since 1998, most of the time as a volunteer