prod · stable since 2004 · pager: carried · audits: passed
Janaka
Premathilaka
Senior Java Engineer & Solution Architect
I build rock-solid enterprise Java systems — and lead them into the AI era.
22+ years of mission-critical banking and public-sector software for UBS, Credit Suisse and the European Commission.
Profile
Proven enterprise tech, practical AI.
I am the engineer teams call when a regulated system must not fall over. In 22+ years of banking and public-sector software I have kept six enterprise applications stable through the Credit Suisse–UBS merger, delivered an audit-grade archiving programme on time, and made a front-office FX platform about 20% faster.
Today I bring that discipline to LLMs, RAG and agentic automation inside the bank’s perimeter — Spring Boot with LangChain, LangGraph, CrewAI, AutoGen and the OpenAI Agents SDK — held to the standard the domain demands. Calm under pressure, explicit about trade-offs, and finished means running in production. The most recent evidence is AssetCare: a Java 25, Spring Boot and Angular application I took from architecture to a live Kubernetes deployment, with AI used to accelerate the engineering rather than replace it.
I also run Janaka Academy: daily notes and learning paths for engineers who intend to surpass their teacher.
Recent build
AssetCare: a production-deployed Java, Angular and Kubernetes application.
AssetCare
assetcare.janaka.me · asset and maintenance management, reference application
Idea to public URL by one engineer: Java 25 and Spring Boot 4.1 behind an Angular 22 front end, Keycloak identity, PostgreSQL 18 with Liquibase, S3-compatible storage, all running on Kubernetes (K3s) with Helm, Traefik and a Let's Encrypt certificate on a Hetzner Cloud server created from Terraform. Tested at every level, scanned, signed and released through GitHub Actions. AI-assisted engineering accelerated the implementation, the investigation and the documentation; the architecture, security, validation and production decisions stayed engineering-led.
Public demo account with sample data only. The story from four angles: the engineering article, the Academy course, the AI-assisted workflow and the public showcase (source on request).
Contact
- Phone+41 76 224 84 45
- Emailjanaka2@gmail.com
- LinkedInin/janakapremathilaka
- Blogjanaka.me/blog
- GitHubgithub.com/Janaka2
Core skills
Engineering
AI / LLM engineering
DevOps & cloud
Versions as they run today in AssetCare: Java 25, Spring Boot 4.1, Angular 22, PostgreSQL 18, Keycloak 26, Helm on K3s. Java 17, Kafka, Oracle and OpenShift are the bank stack.
Languages
Key Metrics
Numbers that hold up.
Experience
22+ years, production-grade.
-
01.2024 — present · Zürich, Switzerland
Senior Full-Stack Solution Engineer (Lead)
UBS / Cognizant
- Full ownership of six enterprise applications through the Credit Suisse–UBS merger — system stability and zero operational interruptions under sustained pressure.
- Led teams through multi-platform migrations and technology decommissioning, resolving high-priority production incidents with calm, decisive execution.
- Led the application-archiving initiative to 100% on-time delivery under audit-grade deadlines; built Linux + Oracle CLI pipelines for multi-gigabyte regulated data feeds.
- Designed and shipped LLM and agentic-RAG automations for internal banking workflows, integrated with existing Java services — including local Llama 3 inference for data that cannot leave the bank’s perimeter.
- Hands-on with the OpenAI Agents SDK and Model Context Protocol (MCP): multi-tool orchestration, guardrails, and RAG-powered enterprise applications in Python.
- Mentor junior engineers, lead code reviews, carry the on-call (Pikett) pager.
Java 17Spring BootKafkaOracleOpenShift / KubernetesReactGraphQLJenkinsn8nLangChainLlamaIndexRAG / CAGOpenAI Agents SDKMCP -
05.2019 — 01.2024 · Zürich, Switzerland · remote from the UK 2019–2020
IT Solution Developer
Credit Suisse / Cognizant
- 100% ownership of the mission-critical Master Data Management tool, built from scratch — the bank’s golden data source for search and reporting.
- Architected and delivered three cloud-native applications end-to-end (Spring Boot, React, Oracle, microservices), including a web application for dynamic consumer endpoints and case-management tools with streaming integration.
- Low-latency front-office FX trading platform (Java 11–17): ≈20% responsiveness gain through multithreading and memory tuning.
- Built the team’s CI/CD, Kubernetes/Docker and observability pipelines; championed TDD with JUnit and Mockito.
Java 11–17Spring BootReactGraphQLKafkaLiquibaseOracle / PL-SQLOpenShiftHelmSplunkGrafana -
01.2018 — 05.2019 · Zürich, Switzerland
IT Solution Development Specialist
UBS / Cognizant
- Modernised 20+ legacy components into Spring Boot microservices with robust solution architectures.
- Automated Jenkins delivery pipelines; migrated the codebase from SVN to Git.
- Strengthened testing with JUnit, integration tests and Cucumber BDD.
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06.2011 — 01.2018 · Brussels, Belgium
Senior Full-Stack Java/JEE Developer
European Commission (DIGIT Division)
- Engineered and maintained the EU’s core e-procurement system — mission-critical, multi-language, public-sector — over a 6.5-year tenure; the system contributed about 40% of the department’s total revenue.
- Distributed integration flows with Spring Integration; JBPM workflows for approvals, escalations and audit trails.
- Full-stack delivery (Angular, Spring/Hibernate, EJB3, Oracle, WebLogic); release ownership and L3 production support.
JEEAngularJBPMSOA -
05.2004 — 06.2011 · Belgium & Sri Lanka
Senior Java/JEE Consultant & Engineer
Johnson & Johnson · Nokia Siemens · Union Bank of Colombo · and others
- Core technical consultant across healthcare, telecom, banking and e-commerce — enterprise-grade Java/JEE solutions.
- Union Bank of Colombo: core banking modules — loan system, lease schedules, cheque and passbook printing (EJB2, JSP, DB2 on AS/400).
- Modernised architectures in Agile/Scrum settings; SOAP/REST integration; Oracle/MySQL optimisation.
After beginning my career in Sri Lanka, I spent nearly a decade in Belgium working with ABSI, Roomsnet.com and Simbios on projects for clients including Van Genechten Packaging, Nokia Siemens Networks and Johnson & Johnson. This period gave me broad exposure across healthcare, hospitality and enterprise IT, before I joined the European Commission – DIGIT Division to deliver large-scale e-procurement systems. Since 2018, I’ve continued my journey in Switzerland, leading full-stack engineering and AI integration at Credit Suisse and UBS.
My journey began in Sri Lanka, where I started as a computer science instructor and soon entered the banking world at Union Bank. In 2008, I moved to Belgium, and the decade that followed became a transformative period of growth in my career.
I worked with ABSI in the healthcare sector, later joined Roomsnet.com as a Java/JEE Developer and Technical Lead in the hospitality domain, and collaborated with Simbios on projects for clients such as Van Genechten Packaging, Nokia Siemens Networks, Johnson & Johnson and Centric IT Solutions.
In 2011, I joined the European Commission – DIGIT Division, leading the development of robust e-procurement systems and complex workflows for the EU.
Since 2018, Switzerland has been my base — with UBS and Credit Suisse at the centre of my journey, where I’ve focused on high-performance full-stack engineering, system migrations and the integration of AI-driven automation.
Independent Projects
Five products, idea to production.
Built in my own time and on my own equipment, independently of my employment and unrelated to my employer’s business. All five are live, all five are for sale, and all five are private by construction.
nüchtern
nuechtern.appA fasting companion that keeps the biology visible — phase timer, hydration, electrolytes. German and English.
Open ↗Daily Momentum
daily-momentum.comA quiet record of where the day went. One tap says what you are doing; everything else is derived.
Open ↗Loop
loop.janaka.meA memory for the things that repeat. Note when it happened, and the app learns the rhythm from what you actually did.
Open ↗BabyLoop
babyloop.janaka.meKeep the little moments without keeping your phone in your hand. Two taps, a daily summary, a PDF for the paediatrician.
Open ↗LeftHere
here.janaka.meTake a photo. It remembers where — the car, the keys, the bag, the bench with the view — and walks you back.
Open ↗All five: progressive web apps, offline-first, no accounts, no servers. Records stay on the user’s device or in storage the user owns.
AssetCare
assetcare.janaka.me · reference application, source on request, not for sale
The sixth project has a backend by design. A complete asset-maintenance application on Java 25, Spring Boot 4.1 and Angular 22, with Keycloak, PostgreSQL and object storage, deployed on Kubernetes with Helm and Terraform and verified from outside. Where the five products show restraint, this one shows the whole production path executed.
New in autumn 2026
BlitzMath
bm.janaka.meLive maths battles for classrooms and families. Children join with a six-digit code and everyone answers at the same time; one Cloudflare Durable Object per room is the referee. No accounts, no ads, no chat. How it is built.
Open ↗MP3 Alarm Clock
github.com/Janaka2A desktop alarm clock that plays an MP3 or your own recorded voice, keeps the computer awake and wakes it from sleep. One Python file, open source under the MIT licence.
Source ↗How they were built
One engineer, AI in the loop, shipped.
All five products were specified, designed, built, written and deployed by one person — evenings and weekends — with LLMs used deliberately at each step rather than as a novelty. This is the same practice I bring to regulated engineering work: use the model to move fast, then hold the output to the standard the domain demands.
- Product scope and interaction flows drafted against a model, then cut back by hand until only what earns its place remains.
- Implementation in tight generate-and-review loops — I stay the architect and the reviewer, and nothing ships that I cannot explain line by line.
- Interface copy in two languages, and the visual identity of all five apps, produced with AI assistance and edited to a consistent voice.
- Blank page to public URL in weeks, not quarters, with no team, no budget and no outside help.
Any of the five could find a better home.
All five were developed independently of my employment, so they are mine to pass on. If one fits a portfolio you are building, I am open to a conversation about acquisition or licensing — source, brand, domain where applicable, and a documented handover.
Certifications & Courses
Always learning.
Anthropic Claude Academy (2026)
Claude Code 101
Issuer: Anthropic
✓ Badge · completed August 2026
Claude Code in Action
Issuer: Anthropic
✓ Badge · completed August 2026
AI Fluency: Framework & Foundations
Issuer: Anthropic
✓ Completed September 2026
AI Fluency for Builders
Issuer: Anthropic
✓ Completed August — September 2026
AI Fluency for educators
Issuer: Anthropic
✓ Completed August — September 2026
AI Fluency for students
Issuer: Anthropic
✓ Completed August — September 2026
Introduction to agent skills
Issuer: Anthropic · Claude Code
✓ Completed September 2026
Introduction to Model Context Protocol
Issuer: Anthropic
✓ Completed September 2026
Model Context Protocol: Advanced Topics
Issuer: Anthropic
✓ Completed September 2026
Claude Certified Architect — Professional
Issuer: Anthropic
Exam preparation · 2026
Cloud, AI & Automation
CKA — Certified Kubernetes Administrator
Issuer: The Linux Foundation / CNCF
Issued 2024
AI Automation: Build LLM Apps & AI-Agents with n8n & APIs
Instructor: Arnold Oberleiter
✓ 100% complete
AZ-900: Microsoft Azure Fundamentals Exam test 2025 (480Q)
Instructor: Global Edtech
✓ 100% complete
Helm 3 — Package Manager For Kubernetes
Instructor: Himanshu Sharma
✓ 100% complete
The Complete Agentic AI Engineering Course (2025)
Instructors: Ed Donner, Ligency Team
Completed 21 September 2025
✓ 100% complete
Java, Spring & Dev Productivity
IntelliJ IDEA Tricks to Boost Productivity for Java Devs
Instructors: Tao W., James Lee, Jiarui Zhou
✓ 100% complete
Ready for Production with Spring Boot Actuator
Instructors: John Thompson, Spring Ahead Code Academy
✓ 100% complete
Escalate Scala Training — Setup Instructions
Instructor: Dick Wall
✓ 100% complete
Data & SQL
SQL Programming Basics
Instructor: Global Academy
✓ 100% complete
Languages & Soft Skills
Communication & Social Skills
Instructor: MicroLearn Ltd
✓ 100% complete
Remember the German Articles der, die, das (Mini-Course)
Instructor: Anja Winter
✓ 100% complete
Mental Health First Aid Skills
Instructor: Mark Paddock
✓ 100% complete
Mastering Success: Achieve Happiness, Wealth & Health
Instructors: Chris Croft, CRFT Productions
98% complete
First Aid
Instructor: Arthur Jackson
✓ 100% complete
Sun Certifications (since 2006)
Sun Certified Enterprise Architect (SCEA)
Issuer: Sun Microsystems
Issued January 2006
Sun Certified Business Component Developer (SCBCD)
Issuer: Sun Microsystems
Issued January 2006
Sun Certified Java Programmer (SCJP)
Issuer: Sun Microsystems
Issued January 2006
Education
Credentials.
University of Sri Jayewardenepura
BSc — Computer Science, Statistics & Mathematics
1999 — 2004
University of Colombo
BIT — Bachelor of Information Technology
1999 — 2004 · 6 semesters completed
University of Moratuwa
Master’s in Computer Engineering
2007 — 2008 · paused on relocating to Belgium
My Life Journey
From Galle to Zug.
Bachelor’s Degree
1999 — 2004
University of Sri Jayewardenepura
BSc in Computer Science, Statistics, Mathematics
Second Bachelor’s
1999 — 2004
University of Colombo
BIT (6 semesters completed)
Master’s Degree
2007 — 2008
University of Moratuwa
Computer Engineering · paused on relocating to Belgium
Certifications
2006
Sun Java Certifications (SCJP, SCBCD, SCEA)
Want to know more?
Chat with my AI assistant about my experience, skills or availability.