Joel Purra Résumé job@joelpurra.

com

Joel Purra 
CV/résumé — check online for the latest version 

joelpurra.com joelpurra.com/cv job@joelpurra.com

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The ace up your sleeve 
I do freelance software development consulting. Adding new features, refactoring old systems,
building entire greenfield projects and MVPs from scratch. Primarily short-term contracts (0-3 months
with option to extend), optionally part-time (8-40 hours per week), mostly working remotely.
Subcontracting accepted.
Hands-on software development in the entire stack as well as code reviews, designing system
architecture and being an interim CTO. Emphasis on quality code with tests. With a wide range of
skills and experience, I enjoy being the go-to guy. Working full-stack, but prefer backend over
frontend.
Grew up in an entrepreneurial family and have been running businesses since I was a teenager.
Co-founded several e-commerce sites, built tools for the government, done internet/security research,
released dozens of open source projects, advised developers and startups. Have a master's degree
in information technology and engineering, army officers' training, traveled the world with my
backpack, lived in several countries. Prefer to have a flexible lifestyle; am currently a freelance
contractor/consultant. Message me.

Location Berlin, Germany (flexible worldwide and remotely)

Nationality Swedish (implicit EU work permit, company HQ in Sweden)

Experience 
The below experience list excludes several positions, intermediary consultancy firms and links.
Additional positions/entries and details are available on my Linkedin profile page: ​joelpurra.com/cv

Consultant (International) 
January 2010 – present
Gun for hire. I do freelance software development consulting. Primarily short-term contracts (1-3
months with option to extend), optionally part-time (16-40 hours per week), mostly working remotely
(with occasional in-person/video meetings). Subcontracting accepted.
Focused on open source (based) software development. Specialist/senior engineer in web
technologies (full stack; preferably back end but also front end). Ready to dive into app development,
AI, machine learning, etcetera.
Currently preferred tech: backend development in NodeJS, focusing on architecture and scalability.

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Systems Architect, Shing 
March 2017 – present・Remote
Moving Shing forward from an MVP towards a stable SaaS platform for e-commerce in the age of
sharing economy. Providing feedback on business requirements and transforming it to a full-stack
systems architecture. Supporting developers, from junior to senior, in their decisions. Part time, 100%
remote.
Node.js, AWS, microservices, ES2017, message queues. Outsourcing development teams, code
reviews.

Backend Software Engineer, BCG Digital Ventures 
July 2016 – September 2016・Berlin, Germany
Working on the backend in an agile, mid-sized greenfield project for an external Boston Consulting
Group client. Designing the distributed microservice oriented architecture, designing the API for
iOS/Android/web, implementing business logic together with the backend team in close collaboration
with other teams. Contract, 40 hours per week/100%, 80% of work done remotely.
Node.js, microservices, architecture, API, Amazon Web Services (AWS Lambda, S3, SNS, SQS,
DynamoDB etcetera), design patterns, dependency injection, Aurelia, javascript
ES6/ES2015/ES2016, Promises, git, github, Stash, JIRA, agile development methodologies.

Backend Software Engineer, Ohlala.com 
May 2016 – June 2016・Berlin, Germany
Refactored the entire backend, stepwise taking the company from an MVP to a stable platform for
international customers. Architectured a promise-based implementation together with the CTO,
working towards creating a reliable, tested, distributed, micro-service based architecture. Contract, 20
hours per week/50%, 80% of work done remotely.
Javascript, TypeScript, Node.js, NPM, ES6/ES2015, Promises, refactoring, architecture, git, git-flow,
agile development methodologies.

Software Engineer, KAYAK 
October 2015 – February 2016・Berlin, Germany
Working on the full stack of kayak.com and affiliated web sites, out of the 120+ employee office
(technology center) in Berlin. Collaborated with product managers to implement new features from
scratch, all the way from the database layer, through the java backend, to the responsive frontend.
Solved as well as reported bugs and tickets, mostly on the frontend. Dealing with dynamic site
branding in a shared codebase, localization and internationalization issues. 40 hours per week/100%.
Java, Spring, Tomcat, Keel, Velocity, Javascript, HTML, LESS, CSS, git, JIRA, lots more.

Consultant (Sweden) 
March 2014 – October 2015・Stockholm, Sweden
Technical reviewer of programming books in writing, such as NodeJS Design Patterns for Packt

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Publishing.
NodeJS, design patterns, code review, text review, documentation.
Involved in DNS, DNSSEC software development and promotion through Verisign Labs, NLnet Labs
and IIS.se. The quick hack dnssec-name-and-shame.com has received attention from the DNSSEC
community, and has been presented by top names at RIPE, ICANN conferences. There's even an
official t-shirt.
Web, internet, software development, security. DNS, DNSSEC, getdns, getdnsapi, node.js, mongodb.

Master’s Thesis Researcher 
March 2014 – February 2015・Stockholm, Sweden
Writing my master's thesis researching web page resources in general and ads, web bugs, click/user
trackers in particular, within the .SE top level domain. The thesis was the final step in receiving my
Master’s Degree in Information Technology and Engineering. 40 hours per week/100% for six months,
50% of work done remotely. ​joelpurra.com/projects/masters-thesis/
The paper "Third-party Tracking on the Web: A Swedish Perspective", based on the master's thesis,
has been accepted to IEEE LCN 2016. It was co-written and presented (2016-11-08, Dubai, United
Arab Emirates) by my thesis supervisor Niklas Carlsson, associate professor at LiU.

Research, web, automation, crawling, software development, technical writing. PhantomJS, jq, bash,
HAR, JSON, HTTP, HTML, JavaScript, git, LyX, LaTeX.

Backend Software Engineer, Enginuity Group 
July 2012 – January 2013 (7 months)・Toronto, Canada Area
Developing private demo/minimum viable product for stealth startup. Working with system
architecture, development practices, code review/testing, visualization, cross-operating system
development support, deployment and tools plus introducing new coders to the system. Contract, 20
hours per week/50%.

Built using CouchDB/CouchApp on Cloudant and VM Farms, node.js, backbone.js, Backbone

Marionette, mustache.js, underscore.js, fabric deployment, leiningen, shell scripting, SilverLight 5,
Twitter Bootstrap, jQuery, git/github.

Senior Backend Web Engineer, Mercatus Technologies Inc. 
May 2012 – August 2012 (4 months)・Toronto, Canada Area
Optimizing complicated backend architecture, implementing critical speed improvements before
relaunch of www.PriceChopper.com, a grocery store chain with over 100k likes on Facebook.
Implementing a caching layer to reduce the number of remote API calls. Implementing additional
backend and frontend features after relaunch. Implementing supporting software, proof-of-concept
code/tests for Mercatus' clients. Improving Mercatus' .NET API. Contract, 16 hours per week/40%.
Working with C#/.NET4, ASP.NET MVC3, NHibernate, MySQL, Mercatus API, log4net, Visual Studio
2010, ReSharper. Mercurial HG, Subversion SVN. Javascript, jQuery, AJAX, HTML5, CSS3, XML,
XSD, XSLT.
Architecture. Optimization. Debugging. Caching. Web. Cross-browser compatibility. Maintainability.

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Frontend Software Engineer, Open Source Clinical Application Resource 
(OSCAR) 
March 2012 – August 2012 (6 months)・Toronto, Canada Area
Implementing the front-end for medical intake forms in the Client Access to Integrated Services and
Information (CAISI) submodule for some of the health care providers in Toronto. The submodule is an
integrator to facilitate the seamless flow of medical information in multi-site care. Contract, 10-16
hours per week/25-40%, 100% of work done remotely.

HTML5. CSS3. jQuery. Twitter Bootstrap. Jekyll. PhantomJS. Legacy system integration. Forms.
Usability. Accessibility.

Software Engineer, The Swedish Post and Telecom Authority (PTS) 
August 2011 – January 2012 (6 months)・Stockholm, Sweden
Developing software to manage undeliverable letters and other mail. Three developers, one product
owner developing for eight postal administrators and one manager. Business improvements leading to
improved results for the administrative unit. Working with agile methods. Contract, 40 hours per
week/100%.

System coded in C#/.NET4 with Entity Framework 4.1 Code First against MySQL, ASP.NET MVC3,
Visual Studio 2010, ReSharper, HTML5, CSS3/.LESS CSS, AJAX/jQuery/JavaScript, MS SQL Server
2008, Code Contracts, Pex, MSBuild, NuGet, open-source frameworks/tools Selenium WebDriver,
CruiseControl.NET, NAnt, Castle Windsor, NUnit, QUnit, labJS, Modernizr, Solr, SolrNet, Elmah,
Glimpse, Rhino Mocks, OpenCover, log4net and more.

Architecture, framework evaluation, coding, testing, unit tests, high code coverage, best practices,
refactoring, code cleanup, object-oriented programming, object-relational mapping, user education,
scripting, layout, cross-browser compatibility, usability, maintainability.

Software Developer, Outokumpu Nordic Brass Gusum AB 
February 2010 – June 2010 (5 months)・Linköping, Sweden
Developing client, administration and server software to manage material and products in the brass
industry. Main full time developer, with one tester and three part-time consultants for different
separate, but integrated, systems. Contract, 40 hours per week/100%.

Agile development following Microsoft Solution Framework (MSF) for Agile Software Development
Process, using VSTS/Team Foundation Server for project tracking/source control and SharePoint for
documentation/planning.

System coded mainly in C#/.NET3.5 with MS SQL Server 2005+2008, WPF, ASP.NET MVC, LINQ to
XSD, XML/XSD/XSLT, open-source frameworks NHibernate, NUnit, Rhino Mocks, Sharp
Architecture, Caliburn, log4net and more.

Running in a Citrix environment, integrated with legacy systems (Movex/DB2 on AS/400), custom
GS1-128 barcodes (Datalogic barcode readers), barcode/label writers, legacy printing systems
(StreamServe).

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Architecture, automated unit tests, high code coverage, object-oriented programming, object-relational
mapping, N-tier, multiple front ends/clients, specialized industrial environment, workflow, resource
management.

Hacker, Software Developer, Swedish Defence Research Agency (FOI) 
October 2009 – December 2009 (3 months)・Linköping, Sweden
Developing cyber warfare (hacking) simulation infrastructure and supercomputer/cluster control
software. Part of a team of 17 engineers. Software in use at national and international cyber warfare
(hacking) exercises. Contract, 10 hours per week/25%.

C#, WinForms, SQLite, LINQ to XSD. XML/XSD/XSLT. VMWare, Linux, Windows.

Business analyst/requirements engineer and systems developer, BAE 
Systems Hägglunds 
January 2009 – June 2009 (6 months)・Linköping, Sweden
Gathering system requirements and co-developing a C++ bridge between a CORBA (Common Object
Request Broker Architecture) service and a COM (Component Object Model) application called
www.COM2CORBA.com. Part of the course TDDD09 Software Engineering Project (PUM-projekt)
with six other master students. Now released as open source under GNU GPL.

Team Leader, Swedish Defence Research Agency (FOI) 
October 2008 – December 2008 (3 months)・Linköping, Sweden
Four teams (in Sweden and Estonia) of computer engineering students playing defense in an
international cyber warfare exercise, preparing online server systems against hacking and DDOS
attacks. Working with the web backend (Ubuntu, Lighttpd, WordPress, MySQL), team leader during
attacks -- successfully defending the systems. A joint exercise between Swedish Defence Research
Agency (FOI), The Swedish National Defence College (FHS), The Estonian National Defence College
(KVÜÕA/SIVAK), Swedish Defence Materiel Administration (FMV), SAAB Combitech and Linköping
University (LiU).

Second Lieutenant, Systems Specialist, Swedish Armed Forces 
January 2002 – May 2003 (1 year 5 months)・Enköping, Sweden
Fänrik. In charge of personnel (second in command) and technology at company level. Advanced
systems specialist (Swedish Military Academy for Technology) for all land-based communications
system, including mission critical long and short distance mesh networks. Teaching radio/phone
communications, systems setup to the Swedish Armed Forces of Kosovo (NATO's KFOR) before
deployment.

Education 

Master of Science in Information Technology and Engineering, The 

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Institute of Technology at Linköping University 
2003 – 2015
Master's thesis: "Swedes Online: You Are More Tracked Than You Think"​.
(urn:nbn:se:liu:diva-117075) ​joelpurra.com/projects/masters-thesis/

All courses finished in January 2010. Master's thesis written 2014/2015. 2006, 2007, 2010, 2011,
2012, 2013 was spent working and traveling.
Problem based learning, group projects, computers, programming, networks, math, engineering.
Majored in Media Informatics.

High School Diploma, Computer Technology and Natural Science, 
Forsmarks Skola 
1999 – 2001
Private boarding school for science studies, specializing in computer science and physics/energy
production. Owned and operated as a part of Forsmark Nuclear Power Plant, a subsidiary of
Vattenfall. Designated as the best school in Sweden by the government's Expert Group on Public
Economics (ESO) in a report during my second year.

References 
At least 13 people have written recommendations on Linkedin, and dozens have given skill
endorsements. Contact information and further details available through Linkedin, or upon request.

"I was managing Joel directly as the CTO of Spreefang (Ohlala.com), where I hired him as an interim
software engineer contractor, working part-time remotely and part-time in the office. Our goal was to
redesign the company's "minimum viable product" API/backend written in a custom style, to a modern
NodeJS architecture. The long-term goal is a distributed microservice-based architecture with
reliability and scalability in focus, which was devised with Joel's help. He has long experience in
breaking down an existing, complex solution to manageable parts suitable for distributed execution,
automated testing and highly collaborative programming.
The refactoring uses NodeJS 6 and TypeScript with ES6/ES2015 features, on top of CouchDB, with
multiple tiers connected in a promise-based, asynchronous style. Joel is familiar with a wide range of
tools and techniques, and his sense of order and structure instills trust. With a lot of my focus devoted
to other tasks than refactoring, he was largely left to his own devices solving a large problem by
himself. Within the framework given, he rewrote complex code to much more straightforward code in
components which can be easily reused. This gives us a good base to work towards our longer-term
goals by speeding up both technical and product development.
Having worked with Joel, I can vouch for his dedication to technology and delivering high-quality
solutions, and recommend him to any company which needs a great engineer. He cares deeply about
code quality and architecture, and it's a shame that we can't hire him full-time to our startup. Good
luck and hope to work with you again!"
— Dr. Torsten Stüber, ​Co-Founder & CTO at Spreefang, ​was Joel’s client at Ohlala.com

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"Joel is a pro active problem solver with long years of experience as software developer. He's fun to
work with, reliable and happily shares the broad knowledge he gathered throughout his career which
has been very valuable for the team and the project."
— Daniel Schäfer, ​Full Stack Mobile/Web Developer, ​worked directly with Joel at Ohlala.com

"I met Joel at the 2014 "The Next Web" conference in Amsterdam last year. We were partners in a 36
hour Hack Battle. In that short time we developed and launched dnssec-name-and-shame.com, which
is still up and running today. The web site allows the user to enter any domain and discover if that it is
secured by Secure DNS (DNSSEC). At the end of the hack battle and conference, the web site won
an award from PayPal.
Joel is a "SuperCoder", understanding all aspects of a web site, from registering the domain, setting
up the sites DNS entries, and the bulk of the websites development in a 36 hour period. He was a
great teammate and was a pleasure to work with. Also a quick learner, having to pick up a new API in
a short time to provide the DNSSEC queries.
I would highly recommend Joel for any software related position."
— Tom Cuddy, ​Principal Consultant at NARTech, Inc, ​worked directly with Joel at joelpurra.com

"With great devotion Joel took on the complex problem to identify the scope and use data tracers on
the Internet. The task was complex both in terms of the technical challenge to monitor a large portion
of the Internet and the ethical and social science questions that surrounds the subject area. He
showed a lot of good will and an endurance to independently accomplish this extensive work to a
conclusion."
— Staffan Hagnell, ​Head of R&D at IIS (The Internet Infrastructure Foundation), ​managed Joel at IIS

"Joel has keen eye for structure, and following best practice. He really knows how to keep a
repository looking clean, writes fantastic documentation, and is fun to work with."
— Josh Teneycke, ​Front End Developer and IT Support, Enginuity Group, ​worked indirectly for Joel at
Enginuity Group

"Joel worked on the full stack of the project; from our NodeJS backends to maintaining visualization
code in the front end, as well as taking lead on managing code pushes to the production servers. We
could always count on him to make code thats well-organized, readable and maintainable. And he
would make sure to take a look at our commits and give regular feedback regarding best-practices
and improvements. As an example of his professionalism, upon leaving our team, he made sure that
the transition was as smooth as possible by training myself and other teammates. This was just one of
the many ways that he contributed to the overall productivity of the team."
— Ravi Desai, ​Programmer, Enginuity Group, ​worked directly with Joel at Enginuity Group

"I hired Joel as a developer on a software project I am managing in a stealth start-up in Toronto. This
is the second time I've had the opportunity to hire him; it's something I could not pass on. Joel's role
was to design the system/service architecture, implement several subsystems, improve development

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practices and to aid the other developers with his expertise in web and software development. He's
not afraid to dive into new areas, working with multiple programming languages/libraries and has
helped out a lot when we've been under time constraints. He's also been very helpful in stabilizing and
normalizing the entire multi-server environment across multiple operating systems/platforms to
minimize perceived differences between development and production. We're sad to see Joel leave
Canada for new opportunities and adventures, and would gladly have him work with us in an even
greater capacity - you are welcome back anytime!"
— Paul Bearne, ​WordPress / Technical Consultant, Freelance, ​managed Joel at Enginuity Group

"Joel is a passionate ASP.NET MVC3/C# developer consult. He has a sound understanding of

software development and architecture, and can formulate a maintainable and clean solution to any
problem I presented to him. He is extremely pleasant to work with and is an asset to work with."
— Alan Lok, was Joel's client

"Joel is a motivated and passionate technologist. Joel is committed to resolving complex

software/architectural/web issues quickly and effectively."
— Bohdan Zabawskyj, ​VP - Technology, Mercatus Technologies Inc., ​managed Joel indirectly at
Mercatus Technologies Inc.

"Joel is a skilled developer with a wide knowledge of useful techniques, frameworks and products. We
formed a team to develop an internal tool, where Joel was in charge of the architecture and back end
development. He's got drive and I would not pass on the opportunity to work with him again!"
— Paul Bearne, ​WordPress / Technical Consultant, Freelance, ​managed Joel at rDoing.com

"Joel was part of a project at the Swedish Post and Telecom Authority (PTS) Aug 2011 through Jan
2012 where Attentec supplied all of the designers and developers. The project was a great success
and managers at PTS were very happy with the team from Attentec both regarding competence and
attitude. A key success factor was the agile approach adopted from the very start. I know Joel as a
brilliant developer eager to learn and use the very latest tools and methods to achieve optimum
results. He has good communication skills which allows him to build confidence with end-users
leading to a positive requirements dialog and a great result. I wish Joel best of luck with his
international ambitions and career. I can easily recommend him as a designer and developer and am
happy to provide further details upon request."
— Lars Lundberg, ​Partner and General Manager, Stockholm, Attentec AB, ​managed Joel at Attentec
AB

"Joel is a highly skilled software developer with good knowledge of tools and best practices. You can
be rest assured that code written by Joel is of the latest standards, robust and exceeds your
expectations."
— Johan Govers, ​Software Systems Designer Consultant, Attentec AB, ​worked directly with Joel at
The Swedish Post and Telecom Authority (PTS)

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"I had the fortune to work six months together with Joel on a project where we designed a new a
system. Joel was a great injection of technical excellence and always made sure that the system was
built to hold together and he took no short-cuts. Joel strived for a good test coverage and left us with a
clean nice code. Joel is very social and got along really well with our end users and rest of our
technicians at our company. I believe that Joel would bring value to any project where new technology
is used and there is need of someone “who is willing to try just one more thing to make it better”."
— John Cirverius, was Joel's client

"In Skill's project at FOI, where a lab-environment for IT-safety technicians was developed by 15
people during a couple of months in 2009, Joel was one of the most skillful programmers. Joel is
charismatic, open-minded and a high performance programmer with a genuine interest in
programming techniques. His has a broad network within his area of work and is an explorer in the
field of new software. Therefore Joel also made a terrific job, coming up with a quick solution to a
customer problem, even at Nethouse. If you need an inventive expert I would gladly recommend
hiring Joel."
— Ove Sjöström, was Joel's client

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