Mark Mitchell

Summary

I have over 20 years of Java programming and application development experience across various industries including fintech, telecommunications, and hospitality. I possess practical, hands-on expertise in executing and architecting the modernization of legacy systems, including migration to cloud-native architectures such as microservices. I have strong DevOps skills ranging from cloud infrastructure deployment automation to CI/CD pipeline configuration, with particular focus on AWS environments. During the initial 10 years of my career, I specialized as a full-stack developer, implementing robust middleware and creating feature-rich UIs. Currently, I’m expanding my expertise by integrating AI and machine learning into my technical toolkit to enhance and optimize the systems I build.

Technical Expertise

Core Technologies

• Java (Spring Boot, Spring Security, Spring Cloud, Hibernate)
• API Development (REST, GraphQL, OAuth 2.0, JWT)
• JavaScript/TypeScript (React, Angular, Vue.js, ES6+)
• Database Technologies (SQL, NoSQL, MongoDB, Oracle)

Cloud & DevOps

• AWS (ECS, S3, SQS, Lambda, AppConfig, Cognito, todo - update me)
• Containerization (Docker, Kubernetes, Minikube, Helm)
• Infrastructure as Code (Terraform, Terragrunt)
• CI/CD (Jenkins, GitHub Actions, GitLab CI)

Architecture & Methodologies (todo- update)

• Microservices Design Patterns
• Event-Driven Architecture
• Agile/Scrum, Test-Driven Development
• Legacy System Migration

Professional Experience

Financefair
Fintech platform enabling SMEs to access working capital through invoice trading.

Role & Responsibilities:

• Lead technical architecture and infrastructure modernisation initiatives
• Build and mentor engineering team with appropriate skillsets
• Implement observability solutions and monitoring systems
• Design and deploy secure cloud infrastructure using AWS services

Key Achievements:

• Diagnosed and resolved critical system stability issues by optimizing JVM memory settings, eliminating production crashes
• Implemented comprehensive observability solution using Datadog with custom alarms and dashboards, reducing incident response time by 80%
• Completely rebuilt infrastructure using Terraform, Terragrunt, and GitHub Actions, improving deployment consistency and reducing maintenance overhead
• Enhanced security posture by migrating all services and databases to private subnets and implementing AWS Session Manager, eliminating SSH access vulnerabilities
• Orchestrated migration from EC2/Docker to AWS ECS, improving scalability and reducing infrastructure costs by 40%
• Built and trained a high-performing engineering team, establishing best practices for modern cloud-native development

Workhuman (Integrations Team)
Workhuman provide recognition software to companies enabling employees to recognise and reward each other.

Role:

• Development and maintenance of customer facing APIs and associated security concerns
• Identify process/pipeline/cycle inefficiencies across team & squads
• Provide technical training and advice to squads as part of the integration’s teams modernisation drive

Key Projects:

• Security modernisation for public facing APIs
• Kubernetes sandbox development environment using Minikube, Helm and Skaffold
• Technical training in the form of POCs, detailed documentation, presentations, and recorded videos. Sessions included:
  • Deploying services to AWS ECS (Spring Boot and Terraform)
  • Service security (Spring Security, Ping Federate and AWS Cognito)
  • Various microservice patterns (e.g. Gateway Pattern, Event Driven, etc.)
  • Deploying code with feature flags (AWS AppConfig)

LexisNexis Risk Solutions (Telematics Team)
LexisNexis Risk Telematics provide analytic solutions to car insurance companies using event data provided by automakers.

Role:

• Backend developer responsible for the architecture, development and deployment of Spring Boot based microservices.
• Writing Terraform infrastructure modules & designing AWS deployment pipelines
• Unit, Integrations & BDD Tests using LocalStack.
• Provide technical mentorship to team members.

Key Projects:

• The primary project was developing a set of services responsible for enriching Connected Car event data with Personal identifiable information.
• Services were implemented using Spring Boot & Spring Cloud.
• Data read from encrypted AWS S3 bucket, new data events published to AWS SQS. BDD Tests implemented leveraging LocalStack (AWS docker based emulator).
• Various DevOps related tasks…
  • Write supporting Terraform Modules
  • Resources deployed to AWS using Terragrunt & Terraform via GitLab pipelines
  • Services deployed to AWS Fargate.
  • Continuous Deployment PoC using Github Actions & jFrog

Invoicefair
InvoiceFair is a company that enables SMEs to sell invoices to investors using a bespoke trading platform. They have traded over €1.5 billion through the platform and won Most Disruptive Fintech Award at 2019 Deloitte Financial Services Innovation Awards.

Role:

• Backend developer responsible for the migration of a legacy system to a microservice architecture.
• Prototyping and development of new features.
• Evaluating emerging software technologies and frameworks.
• Provide technical mentorship to team members.
• Identify and address life cycle or process related inefficiencies.

Key Projects:

• The primary project was the migration of a legacy .NET Monolith to a microservice architecture. My tasks included…
• Prototyping various architectures and microservice configurations
• Securing front (Angular) and backend (Spring Boot) microservices using Springs OAuth 2.0 platform security and Netflix’s Zuul router.
• Migrations of .NET services to Spring Boot based REST services.
• Full rewrite of the platforms internal banking API functionality (Spring Boot, SQL server)
• Various external API integrations e.g. Experian Financial reports (WSDL), MoneyCorp banking (REST), Slack (Webhooks)
• Various DevOps related tasks…
  • Configured environment Infrastructure deployments (Terraform and Chef)
  • Setup CI/CD tooling using Jenkins pipelines on a Kubernetes cluster.
  • Creation of a remote developer sandbox leveraging Eclipse Che, allowing developers to spin up fully emulated personal development/debugging environments in minutes, without the need to locally install many programs, frameworks and tools.

The Now Factory (an IBM company)
The Now Factory provides analytics software that helps communications service providers gain real-time insights into their customers by analysing massive quantities of network and business data. It was acquired by IBM in 2014.

Role:

• Applications Team member responsible for developing next generation middleware
• Writing unit tests
• Develop proof of concept products/features utilising latest technologies
• Debug and solve customer issues
• Code reviews
• Participate in scrum development process (planning, estimates, etc.)

Key Projects:

• Developed a data loading CLI module responsible for distributing and loading potentially 100s of millions of records from text files into potentially 80 separate Oracle database instances. A key requirement was high speed loading. Implemented using Java, Spring Batch and SQL Loader.
• Proof of concept next generation data analytics UI. Developed using latest ES6 JavaScript features, NodeJS, Yarn, NMP, React, Redux and many other libraries.

Wedo Technologies
Wedo Technologies provide Revenue Assurance products to communications service providers, which assist in eliminating revenue leakage by reconciling network consumption and billing system information.

Role:

• Full stack development role.
• Writing unit tests
• Debugging and fixing code bugs

Key Projects:

• Responsible for developing the backend of a data analytics application written in Java using Spring, REST, JMS, Presto & Hive.
  
• Developed various features including a formula parser and validation service which involved parsing and validating a grammar and providing detailed feedback to client (that could be used in UI to highlight lexical errors & provide content assist). Implemented using Spring and ANTLR.
• Implemented various features for a data analytics Portlet application container. For example, a configurable charting dashboard using technologies such as jQuery, Highcharts, Struts MVC, Spring services, Velocity, Hibernate, Oracle.
• Expression builder component using jQuery and CodeMirror UI backed by Struts MVC and Spring services

In1Solutions
Provider of Hotel Booking Engine Technology.

Role:

• Responsible for the development of a product called Hotel In1
• Designing and managing the database, writing PL/SQL maintenance scripts, optimising performance, etc.
• Liaising with the Hoteliers system vendor to capture requirements and identify integration issues
• Debugging and fixing code bugs

Key Projects:

• Developed a Hotel booking engine which is used by hundreds of hoteliers worldwide. Implemented using a Flash based UI, Java & EJB middleware. Backed by an Oracle database.
• Integrated the booking engine with several hotelier’s in-house property management systems using various Web Service technologies (SOAP, REST, JAXB, XMLBeans, Axis)

Education

Certifications

• Sun Certified Programmer (Java 5.0)

Athlone Institute of Technology

• H. Dip in Computing (1999-2000)
• B. Eng Polymer Engineering (1995-1999)