Karoline Karkosch

Software-Architect and Fullstack-Developer

Lübeck, Germany

karoline.karkosch@gmail.com

Xing

Resume

Languages

German

English

French

Skills

Docker

90%

I. love. docker. It's the best invention since chocolate in my opinion. I am also a big fan of docker swarm which I use for my private server but especially for larger applications I prefer kubernetes or Lambda.

Golang

90%

I introduced Golang to our team three years ago. That included developing a library with basic functions for which we also had a Java library (these include for example Authentication, Kafka-Connection, Error handling on failed events, an api to get dsgvo-relevant data, automatic swagger documentation and more). The first Golang service was then also developed by me and I trained the other developers.

Terraform

90%

I use terraform almost daily and have already worked on developing open source providers.

Kubernetes

90%

I could gain a lot of experience with Kubernetes while working at Dr. Klein. The configuration of deployment-files as well as the scaling and debugging of pods is part of my daily work.

Kafka

90%

Kafka-Events are the main way in which data is distributed between microsvervices and it is the heart of our infrastructure. So to understand its workings is an important part of the daily debugging.

Python

30%

I have some basic experience with Python.

Java Spring MVC / Kotlin

90%

A lot of my private projects were built with Java Spring which was also the main framework used in the backend services at Dr. Klein and Finanzguru.

REST, HTTP, Websockets, SSE

90%

These three protocols are my daily bread and butter and I would hope to know them pretty well.

DevOps

85%

I have a pretty solid understanding of most devOps tasks relating to hosting Webservers. I have worked with a wide range of servers from maintaining and migrating legacy LAMP-stacks installed directly on linux servers up to more professional setups with AWS-infrastructure managed by terraform.

Web-Frontends

80%

Starting with old plain javascript via jQuery all the way up to frameworks like Angular, Svelte or React I feel almost at home in the frontend as in the backend. Material-Styling and responsive design are always a core part as well as PWAs and obviously HTML and CSS.

Git

90%

I used git for all of my private and professional projects so far so by now I have a few years of experience using it.

SQL

90%

Most of the stateful applications I work with store their data in relational databases so working with them is part of daily routine.

PHP

60%

I know my way around php and developed quite a few applications with it. Recently it has lost its charme for me though and I currently prefer developing with Golang.

DynamoDB

70%

I worked mainly with DynamoDB at Moia and Finanzguru.

Angular

90%

Most applications on which I worked are built with Angular so I'm pretty familiar with that framework.

React

75%

When working at Finanzguru I gained a lot of experience using React in productive applications.

Vue, Svelte

30%

Frameworks with which I already worked but not on any large-scale projects.

Self-organization

90%

Engagement

100%

Curiosity

100%

Positive attitude

100%

Education and Occupation

Senior Fullstack Developer and Infrastructure Engineer at Finanzguru by dwins GmbH

Apr 2023 until Current

My first project here was introducing Kafka as a message broker to improve various processes which have been a synchronous "fire-and-forget" in the past and needed various cleanup-batches which tried to repair incomplete states. I setup a Confluent Cloud Kafka cluster and developed a Kafka-Library which could be used in the Kotlin-services and worked with the developers to improve the understanding of how an event-driven-architecture could be introduced feature-by-feature to improve existing and future workflows.
Another project of mine was introducing a pipeline for the terraform-repository to enable developers in each team to apply their changes independently and not be blocked by terraform-changes from other teams.
I also developed a pipeline for the batch-jobs to enable developers to start their batch individually without needing to worry about conflicts with other batches.
Features for the customers and consultants I developed included for example: A document-verification-process that enabled customers to change their personal data and have the required documents automatically redirected to the corresponding insurance company, a management-tool with which team-leads were able to independently manage the permissions of their team members or a feature to automatically connect a free sales-consultant with a customer for an instant-appointment.
My latest project was developing an AI-Chatbot-prototybe to be evaluated in an A/B test in the app.

Senior Cloud Engineer at Moia GmbH

Jan 2023 - Apr 2023

As Cloud Engineer at Moia I worked mainly with Golang, DynamoDB, EventBridge, managing AWS-Multi-Account-setups and more. My tasks included developing new services like an automatized setup for Github-team-assignements based on group-assignements in Okta, the configuration of a new terraform provider and automated AWS policy-validation in Github workflows.

Software-Architect at Dr. Klein Privatkunden AG (Hypoport)

May 2021 - Oct 2022

As a Lead Developer and Software-Architect I led projects like introducing Golang as a new language for our microservices, refactored our pipeline-process to version-control the current state of kubernetes, build a Webhook-System that could distribute events from any context and more.

Fullstack-Developer at Dr. Klein Privatkunden AG (Hypoport)

Mar 2019 - May 2021

While working at Dr. Klein in Lübeck I could expand my knowledge about a lot of technologies like Java / Java Spring, Golang, AWS (S3, SNS, SQS, IAM, KMS, EC2, Secret Manager etc), Kubernetes, Angular, Continuous Integration etc. and learn many new things.
My main focus is on on backend development and architecture in a distributed microservice-architecture with communication via Kafka and REST-endpoints. I mainly work on Java Spring services but occasionaly develop an Angular frontend or do dev-ops tasks like configuring Kubernetes deployments, BitBucket Pipelines or AWS configurations.

PHP-Developer at eos.uptrade

Mar 2018 - Feb 2019

The company eos.uptrade GmbH develops Online- and mobile- shops for public transport companies (HVV, Nah-SH, S-Bahn München, S-Bahn Berlin, Wiener Linien and over 80 more). Eos.uptrade maps the oftentimes complex tariff systems in their software, generates the tickets for customers and offers a lot more features with their software.
My area of responsibility ranges from PHP-development over database-maintenance and the instantiation of new systems up to CSS- and Javascript-adjustments. At eos I had the chance to gain experience in object-oriented development in large teams and deepen my knowledge about PHP, Symfony, jQuery, Bootstrap, Docker, Jira, Jenkins, Graylog and a lot more tools.

Bachelor at mindsquare

Oct 2017 - Jan 2018

Three of my most informative, interesting, fun and exhausting months of my life were spent at the company mindsquare GmbH where I wrote my bachelor thesis about developing a Lightning application for Salesforce. I learned a lot during that time - Not just about Salesforce, how to structure an academic paper and programming in large systems, but also about soft skills, how to improve your working environment, teamwork and understanding of your customer. At the end of my studies I decided against the life of a consultant but I am very glad for the experiences and important skills I gained from my time at mindsquare.

University of Luebeck

Oct 2013 - Apr 2018

After finishing school I studied computer science at the university in Luebeck. The core area of my studies was Security in IT and I finished my studies in April of 2018 with the grade 2,6.

Gymnasium Wentorf

until 2013

In 2013 I received my diploma (Abitur) from the High school "Gymnasium Wentorf" with the grade 2,1.

Student coaching

Jun 2011 - Oct 2013

During my time in school I already coached students between the 1st and 6th grade. The coaching lessons were organized over differnt contact channels. For example one teacher of mine suggested me for another student of hers which was struggling in english.
During my studies at university I worked for the agency NachhilfeCoach, who connected me to more students and while I taught a broad spectrum of subjects for the first few years (chemistry, geography, english, maths, physics, biology, history), my focus shifted more and more towards teaching maths in the last year of german High School (Abiturvorbereitung), which I taught almost exclusively in the last few years.

Projects and Goals

What I am working on

Jan 2015 - Current

Here you find a list of current and finished projects from me:

Lionafire Notes

100%

Since I was not happy with OneNote as my primary NoteApp anymore and could not find an alternative I liked after trying Evernote, Simplenot etc., I wrote my own: lionafire-notes.com

Chat-App

10%

To practice better software-architecture and learn new technologies I started developing a chat-application which should enable users to register, add friends and talk to each other in self-created chatrooms.
The server is based on Java and can be accessed by any application that can open a socket connection. The frontends I am currently building are an Android App, a Java application and a web-frontend.

Phoenix-Finances

70%

My first version of this was the first website I ever built myself and consisted of a PHP backend with Bootstrap-CSS and jQuery in the frontend hosted in apache directly on an ubuntu server with cronjobs and manual certbot configuration. A few years ago I upgraded it to an Angular Frontend with a Golang backend hosted in a docker swarm environment with traefik for automatic ssl-certificate generation. The reason for developing it was that none of the existing tools I could find like YNAB etc. provided the features I wanted to be able to control and visualize transactions and "virtual budget accounts" in the way I wanted. So I built my own version according to my own requirements: phoenix-finances.com

Doma Website

100%

I upgraded the web-presence of the Doma Clasica, a horse riding group which I am also a member of.

Homepage

95%

The Webpage you are currently on is also one of my projects. It may look like static html-content but actually there is a lot of dynamic rendering when creating this site: Amongst other things the translations(to try it out press the button below "Languages") are dynamically generated with PHP. The different milestones in my resume and my abilities are also generated from an xml to make it easier to change the styling.

Doctor's office

100%

I developed a website for a small doctor's office for which I built a simple CMS-Backend with PHP with which news could easily be updated by the staff. Since it was only very few fields that needed to be saved, the data is simply stored in a JSON-file so that no database needed to be configured at the hosting company. The editing is done with a WYSIWYG-Editor.

CMS

100%

For Christmas I decided to gift all my cousins their own website including a domain, a (self-built) CMS-Area and a prepared default template. My main goal was that it should be possible to customize the page a lot with very little effort (only upload a few images or texts). That's why the color scheme for headings can be chosen by the user and images take up a large amount of space while the default-menu can be set to transparent so not all pages look similar.
A new challenge was my goal to automate the creation of a new instance -> it should automatically create an SFTP-user (the receiver of the gift can use that to directly upload HTML-files if he/she preferred that over the CMS. Their log-files are accessible here as well.), setup the database inclusive their own database-user with an automatically generated password and filling the database with testdata so the page doesn't start out empty all up to registering the spring-boot-instance in a cronjob to restart on reboot.
In the end my script only needed to be started with the domain that this instance should run on as well as the username and the port and it will execute all above described steps (and a few more) to create a working instance. The generated passwords (e.g. the Login for the CMS) is stored in a secured Log-file that I can access as the server admin (obviously the CMS-password is changeable in the CMS after the first login).
I also automated the configuration of the Server including installing git, Java and mongodb all up to creating an admin-user for the database, configuring apache etc. so that now the script can be run on a fresh Ubuntu system and then each instance can be created with a simple command. That was very useful for setting up the 12 instances that I needed. (including some test-instances)
In this project I learned a lot: about shell scripts, mongoDB, Java/Java Spring and many more technologies and techniques.

Ulrich Bitter

100%

I designed this page for Mr. Bitter according to his design wishes. Before my update the page was realized as an Adobe Flash-Application which meant, it had no responsive design, zooming was not possible, texts could not be copied and the content was displayed statically in the top left corner of the monitor. Mr Bitter also had no option to change texts or images by himself (e.g. make changes in his price list).
I had to start from scratch to redesign the page in HTML, make it responsive and I also designed a CMS-Editing-Area where Mr. Bitter could change texts, images and uploaded files (for example pdf-articles) himself.

Ina Krüger-Oesert

100%

In 2016 the website from Ina Krüger-Oesert received a relaunch by me which included a more modern, responsive design and a CMS-Editing-Area for Mrs. Krüger-Oesert where she could easily enter new dates for workshops she was planning, edit texts and images, add new horses and more functions.

Stable-duty organizer

100%

I developed a Webpage during my time in a local stable where we used to have a physical calendar hanging in which we noted which person had stable duty on which day. Since it was at times a bit annoying to have to drive to the stable to see whether you had duty today and you couldn't swap days with someone else from home but had to drive to the stable for that as well I decided to improve that process.
It's a pretty simple program where each user can assign himself a regular day of the week (e.g. Wednesday) for which he is automatically assigned but he can swap individual days (e.g. if he can't do it one Wednesday he can swap with someone who has Tuesdays in a certain week).
Users also have the option to choose a color in which their name is displayed in the calendar, change their name and password, check an option to stay logged in for 30 days instead of 30 minutes and there is also an admin panel in which the stable owner could add and delete accounts and see which account was assigned to which day.

Weseby

100%

The Weseby-Seite-page is a symfony-based website on which the owner can add and edit images and texts on a simple UI where it is also possible to arrange them with drag- and drop.

What I wanna learn and achieve

Although I am already very experienced with many technologies there is never nothing left to learn. These are some things I still wanna improve on:

Better understand data mesh
work in an international company
work with database sharding
development close to hardware - something with cars and Arduinos
Develop a really cool project with AI

Hobbies

Cycling

Since I was able to cycle until Current

Riding my bike is not just my first choice of transport, I also participated in sporting events with it - for example in a Triathlon-relay in Hamburg.

Carpeting

In my free time I like to build self-designed furniture made out of wood - half of my shelves came into existence that way and it is an activity I enjoy a lot.

Horse-Riding

since 2000

I love horses. Not just riding them but also working with them on the ground. I am a big fan of liberty and horsemanship. My role models are pople like Iseulys Deslé, Anja Beran, Bent Branderup, Irene Raab-Hinrichs, Ina Krüger-Oesert and other people who put the wellbeing of the horse before competitive ambitions.
After 20 years of dreaming I was finally able to fullfil my dream of owning a horse and Galeon has since become the second-most important man in my life.

Internship with Ina Krüger-Oesert

Okt 2016 - Dez 2016

I spent the winter of 2016 in the stable of Ina Krüger-Oesert. During that time I took care of the horses by feeding them, moving them to their assigned paddock, cleaning the stables, watering them and helping riding students with preparing their horses. I enjoyed the privilege of getting lessons from Mrs. Krüger-Oesert on her perfectly trained horses and could also join smaller shows for example a quadrille on the Day of the Horse.
I also improved on my programming skills: On my free day I drove back to Lübeck to attend further studies at my university and I spent the remaining time developing a website for Mrs. Krüger-Oesert where she could independently insert dates of planned workshops and manage other displayed information.

Paragliding

2017 - 2013

During my last three school years I spent most of my summer holidays in Menzenschwand where I was taught by the Flugschule Airpower and spent many fun hours flying.