Kiriakos Krastillis

Tech Lead: API Experience Platform

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Nickenich, Germany

Experience

Nov 2023 - Present
2 years 3 months

Tech Lead: API Experience Platform

OTTO

  • Eliminate friction in API development within the IT organization through technological tools or organizational changes
  • Technologies: Keycloak, Terraform, CI-CD (Github Actions), React, Node.js, TypeScript, Redocly, AWS (ECS, Lambda, EKS, RDS, SNS, SQS, Route 53, EFS, S3), Kubernetes, PostgreSQL, Postman, OpenAPI, AsyncAPI, Kafka, pact.io, Docker, CDE, WSO2, Axway Amplify, Gravitee, Go, Gingonic
Apr 2022 - Sep 2023
1 year 6 months

Backend Engineering Lead

AMVLET / SCOVR

  • Created backend, machine learning, chat, and infrastructure landscape for the SCOVR app and led the backend team
  • Technologies: Kotlin, Quarkus, Hibernate, FaceTec, Keycloak, Terraform, CI-CD (Github Actions), Python, TensorFlow, Keras, GloVe, FastAPI, Gunicorn, ELM, AWS (EKS, RDS, SNS, SQS, EC2, Route 53, EFS, S3, DocumentDB), Kubernetes, PostgreSQL, Postman, OpenAPI, Docker, Mesibo, Dockerized local development
Jan 2022 - May 2022
5 months

Service Rewrite

BDK (via 58 agents)

  • Replaced an old Java EE data import service that only allowed JDBC integration with a modern tech stack offering REST and GraphQL APIs
  • Technologies: Java, Quarkus, Jenkins, Ansible, CI-CD, AWS, Kubernetes, Terraform, Hasura, React, PostgreSQL, Dockerized local development
Nov 2021 - Dec 2021
2 months

PoC Bridge between Cardano and Filecoin

Self-employed

  • Developed proof of concept for a bridge between the Cardano and Filecoin blockchains to enable Cardano users to contract data storage on Filecoin, funded by the Cardano Foundation; project evolved into permanentum.io
  • Technologies: Haskell (cardano-node, Plutus, postgresql-simple), Elm, Docker, IPFS, Filecoin, DevContainers
Jul 2021 - Oct 2021
4 months

Codebase Refactoring

Böhringer Ingelheim (via 58 agents)

  • Supported and coached the team, reduced technical debt, improved software development hygiene, enhanced frontend state store usage, and resolved numerous bugs
  • Technologies: TypeScript, Angular, Redux, Java (Spring Boot, Hibernate, OpenAPI, ArchUnit), Node.js, OpenShift, MinIO
Nov 2017 - Jun 2021
3 years 8 months

Team Lead - Software Engineering

PwC Digispace

  • Built a high-throughput software development department, led teams, and performed hands-on software development
  • Guided transformation from matrix organization to self-determined teams, established developer recruiting, fostered developer culture, introduced an agile mindset among staff and partners
  • Delivered first PwC Assurance software products developed in Germany, championed lean principles, servant leadership, and lead by example, and conceptualized and implemented various blockchain product ideas
  • Technologies: Java, Spring (Spring Boot, Hibernate, Orika, Bucket4j), API Blueprint, Vue, Elm, Haskell (Servant, Parsec, Persistent, Aeson), Python (Flask, scikit-learn, NLTK), GitLab, Kubernetes (OpenShift, K3s, Rancher), Ansible, Ethereum, IPFS, Kafka, containerd, Tern, Harbor, JFrog, Black Duck
Apr 2015 - Oct 2017
2 years 7 months

IT Consultant

Monday Consulting

  • Provided application and enterprise architecture consulting (CoreMedia, WebForms, and greenfield solutions), led integration projects including Boots.com relaunch, and supported the OTTO B2C team as senior engineer
  • Introduced best practices in product development and enterprise culture and contributed to software development
  • Technologies: TOGAF, Git, Jenkins, Bamboo, Linux, Java EE 7, Java 8, JavaScript, Bash, Spring, Maven, UML, OpenStack, Kubernetes
Sep 2013 - Apr 2015
1 year 8 months

Technical Lead

Glanzkinder GmbH (Cancom Group)

  • Led a technical team of 12 (8 developers), managed workflows and requirements modeling, acted as Scrum Master, formalized conventions, testing, pair programming, introduced best practices, performed software development and customer consulting
  • Technologies: Git, Jenkins, Linux, Java EE 7, PHP 5, JavaScript, Bash, Python, Liferay, GlassFish, ExtJS, Java, Spring, Maven, UML, Scrum
Oct 2012 - Sep 2013
1 year

Senior Backend Developer

Glanzkinder GmbH (Cancom Group)

  • Designed and modeled CMS requirements, developed CMS, advised on back-end architecture, developed frameworks, and performed data mining
  • Technologies: UML, PHP 5, SQL, JavaScript, Python, Linux, Git, CakePHP, Yii
Oct 2009 - Dec 2009
3 months

Developer

Lectus Publishing

  • Automated internal IT processes, developed CMS (Joomla extensions and vanilla PHP), built web spiders, and performed SEO
  • Technologies: PHP, JavaScript, MySQL, AutoIt v3, cURL
May 2009 - Oct 2012
3 years 6 months

Lead Developer

KIND Studios

  • Led projects, developed CMS solutions (Yii, WordPress), created frameworks, and performed Linux development
  • Technologies: AWS, UML, PHP 5, SQL, JavaScript, Python, Linux, Git, Yii, jQuery, MooTools, AutoIt v3, Photoshop, GIMP
Jul 2008 - Oct 2009
1 year 4 months

Founder & Developer

aether3d.com

  • Developed a 3D engine and CMS solutions
  • Technologies: Shockwave 3D, PHP, JavaScript, MySQL, Linux
Aug 2007 - Aug 2008
1 year 1 month

Conscription

Greek Military Service

  • Completed mandatory military service in Greece
May 2003 - Jul 2007
4 years 3 months

Event Manager

LP loving-people.com

  • Managed event operations including DJ bookings, marketing, and venue scouting

Skills

  • Lean Thinking: How Much Organization Do We Really Need? How Do We Make Sure We're All Pulling In The Same Direction? How Often Do We Need To Ask These Questions For This Scope?
  • Purpose-driven Leadership: It's Helpful To Motivate Employees And Organizations With A "Why", To Find Out With Them "What" Their Goal Should Be And To Give Them The Right Freedom On "How" To Reach It.
  • Fail Fast & Fail Safe: Promoting An Error-tolerant Culture Is Essential Today At All Levels Of The Organization. Developers Want And Need To Learn From Their Experiments, Ideas, And Decisions. But In Larger Organizational Structures, It’s Also Important To Have Success And Fail Indicators And To Deal With Them Openly And Confidently. I Always Enjoy Supporting And Creating Formats For Sharing Such Learnings.
  • Scaled Agile: Safe, Less, Nexus Are Great Frameworks. When Implementing Scaled Agile, It's Important To Stay True To Your Own Identity And Take A Non-religious Approach With Rich Feedback ("There Is No Silver Bullet" - Agile Swarming – Dan North).
  • Enterprise Architecture: Applying The Togaf 9.1 Framework, Adapting Methodologies, Capability Modeling, Strategic Alignment, Etc.
  • Software Architecture: Domain Analysis, Complexity Analysis, Solution Architecture, Etc.
  • Product Architecture: Leadership Roles In Product Development And Strategic Setup Within Long-term Teams/projects.
  • Documentation Methodology: Methods For Building Single Version Of Truth (Svot) Constructs In Large Companies. Living Document Principle, Web Api Documentation Using Api Blueprint.
  • Continuous Integration & Deployment: Gitlab, Bamboo, Jenkins, Teamcity, Automated Code Quality Analysis (Sonar), Project Templating, Git Workflows, Programmable Quality Gates, Blue/green, Canary, Rolling Deployments.
  • Git: Developing Flexible And Effective Strategies For Source Code Management, Converged Code Management And Release Dependency Modeling Using Git Submodules. Multi-remote Architectures In Git, Git Deploy, Continuous Integration Triggers, Etc.
  • Linux: Server Development And Operations, Building Full-stack Web Hosting Services (From Dns Servicing To Applications). Automating Tasks, Debugging Various Services, Personal Desktop Os, Devops.
  • Configuration Management: Ansible, Terraform, Cloudformation, Each Has Its Own Charms And Pitfalls
  • Compliance & Due Diligence: Ensuring Compliance Of A Team's Software Outputs, Sonarqube Setups, Black Duck, Tern, Copper (K8s), Polaris (K8s), Due Diligence Reviews Of Software Companies And Products, Either For Purchase Valuations, Purchase Compliance, Or Carve-out Needs.
  • Declarative Environments: Kubernetes (Openshift, Rancher, K3s), Vagrant, Docker, Lxc
  • Java: Java 7-13, Java Ee7, Spring, Spring Boot, Orika, Coremedia, Hibernate, Jax-rs, Jersey, Glassfish, Tomcat, Etc.
  • Php: Zend, Yii, Cakephp, Symfony, Codeigniter, Self-built Frameworks And Dependency Injection Containers.
  • Python: Django, Flask, Boto, Scikit-learn, Pypy.
  • Mysql: Installation, Configuration, Administration, Development Of Detailed Schemas And Their Behavior, As Well As Custom Triggers And Stored Procedures, Etl Workloads.
  • Sqlite: Mobile App Databases, Structured Logging.
  • Oracle: Web App & Etl Use Cases.
  • Javascript: Ui Development With Jquery, Extjs, React.
  • Cloud (Amazon Web Services, Azure, Openstack): Creating, Maintaining, And Developing Web Applications, Email Servers, Dns Systems, Vpns, File Systems. Openstack Hamburg Meetup 2015–2018.
  • Octave: Creating Basic Clustering And Feature Recognition Algorithms For Machine Learning.
  • Haskell: Creating Small, Purely Functional Stream Processors, Working With The Xmonad Window Manager. Haskell Is A Very Powerful Tool For Broadening A Developer's Horizons. I Enjoy Organizing Workshops Where I Introduce Property-based Testing With Quickcheck Or Type-based Apis With Servant.
  • Message/event Driven Systems: Kafka, Streaming Apis, Etc.
  • Serverless: Actually Only Openfaas, So "Self-hosted Serverless" And Not Out-of-the-box.
  • Database Design: Designing And Developing Relational Schemas, Replication, Clustering, Sharding, Creating Denormalized High-performance Structures (Triggers Or Other Etl-based).
  • C: Cuda And Low-level Hobby Applications.
  • Bash: Linux Server Automation, Git Hooks, Project Workflow Tools, Helper Tools, Etc.
  • Data Mining: Statistical Analysis Of Datasets With R And Sql, Data Preparation For Other Processes.
  • Big Data: Hadoop.
  • Machine Learning: Feature Analysis, Cluster Detection (K-means).
  • Tdd/bdd: Junit, Mockito, Jbehave (Or Gherkin), Selenium Webdriver (Ui Validation And Behavior Verification), Component Or Product-level Integration Tests, E2e Tests, Api Tests With Postman Or Dredd, Cypress.
  • Agile Methodologies: Xp, Kanban, Scrum, Lean, Moscow, Timeboxing, Pragmatism & Common Sense.
  • Rest & Async Apis: Developing And Consulting On A Wide Range Of Apis Based Either On The Rest Principle Or Asyncapi Approaches With Underlying Technologies Like Kafka/sns-sqs/etc. Applying Hateoas. Openapi, Asyncapi, Api Blueprint Ecosystems (Postman, Redocly, Pact.io, Wiremock, Spectral, Zenwave, Dredd, Drakov, Aglio, Etc.)
  • Blockchain: Running And Developing Various Blockchain Projects At Work And In Free Time (Ethereum Nodes, Smart Contracts, Cardano Stake Pools, Plutus Smart Contracts, Various Cardano Indexers, Filecoin, Technical Analysis Of Blockchain Concepts).

Languages

Greek
Native
German
Advanced
English
Advanced

Education

Oct 2001 - Jun 2006

Höhere Technische Lehranstalt Serres

Bachelor's degree, Civil Engineering · Civil Engineering · Serres, Greece

Oct 1998 - Jun 2001

Lyceum Chrisoupolis

Greece

Oct 1996 - Jun 1998

Gymnasium Keramoti

Keramoti, Greece

...and 3 more

Certifications & licenses

Certified TOGAF 9 Enterprise Architect

The Open Group

Computing For Data Analysis

Johns Hopkins University

Machine Learning

Introduction To Artificial Intelligence

Introduction To Databases

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