Nikolas Lahtinen

Software Developer

Oikotie Asunnot is one of Finland's most-visited residential real estate portals, serving millions of property seekers and connecting them with agents and private sellers nationwide. As a full stack developer on the platform, I contribute to the entire application lifecycle — from designing and implementing new user-facing features to optimizing backend services and maintaining the infrastructure that supports high-traffic loads.

My day-to-day work spans the full technology stack, including PHP and MySQL on the backend, Solr for search indexing, and Angular on the frontend, all running on AWS infrastructure. I focus on delivering features that improve the property search experience while ensuring the platform remains performant and reliable at scale.

Beyond feature development, I drive improvements to the CI/CD pipelines that enable the team to ship with confidence, and I have been instrumental in integrating AI capabilities into the platform — exploring how large language models and intelligent automation can enhance both the user experience and internal workflows.

Senior Consultant, Partner

As a co-founder and senior consultant at PHZ Full Stack, I have spent over a decade building a consultancy that bridges the gap between emerging technologies and practical business solutions. The company serves clients ranging from early-stage startups to established enterprises, delivering expertise across the full spectrum of modern web development, cloud infrastructure, and DevOps practices.

My role encompasses both technical leadership and business development. On the technical side, I research and prototype new web technologies, evaluate their production readiness, and architect solutions tailored to each client's specific needs and constraints. This continuous R&D work ensures that the consulting practice stays at the forefront of an industry that evolves rapidly.

Over the years, PHZ Full Stack has become a trusted partner for organizations seeking to modernize their technology stacks, migrate to cloud-native architectures, or build new digital products from the ground up. The breadth of engagements has given me deep exposure to a wide range of domains, technology stacks, and organizational challenges.

Software Developer

SokoPro is a document management platform designed for the construction and real estate industries, enabling project teams to organize, share, and track critical project documentation throughout the building lifecycle. I joined as a full stack developer to help expand the platform's capabilities and deliver new document workflow features to its growing user base.

On the frontend, I built interactive interfaces using TypeScript and React, focusing on usability and responsiveness for users managing large volumes of project documents. On the backend, I worked with a graph database architecture powered by Neo4J alongside PostgreSQL, leveraging the strengths of each — Neo4J for modeling complex document relationships and access hierarchies, and PostgreSQL for structured data and transactional integrity.

Cloud Engineer

Heeros provides cloud-based financial management software for Finnish businesses, offering solutions for accounting, invoicing, and expense management. As a cloud engineer, I designed and built serverless applications using AWS SAM, Node.js, and React to extend and modernize the platform's service offerings.

My work centered on architecting cloud-native microservices that could scale elastically with demand while keeping operational overhead low. By leveraging AWS Lambda, API Gateway, and other managed services through the SAM framework, I helped the team adopt an infrastructure-as-code approach that improved deployment reliability and accelerated the development cycle. The role also involved building responsive React frontends that connected to these serverless backends, delivering end-to-end features from the user interface through to the cloud infrastructure layer.

CloudOps / DevOps

Working within the City of Helsinki's digital services organization, I helped establish and mature the cloud infrastructure practices that support the municipality's portfolio of citizen-facing applications and internal services. My primary focus was on automating infrastructure provisioning using Terraform and managing containerized workloads on Kubernetes.

I designed and maintained infrastructure-as-code pipelines that enabled development teams across the organization to deploy services consistently and reliably. This involved defining reusable Terraform modules, configuring Kubernetes clusters for multi-tenant workloads, and building the CI/CD integrations that tied everything together.

System Developer

Grano is Finland's leading printing and media company, and I was brought on to design and build a modern e-commerce platform that would transform how the company's customers order printed materials online. The solution I architected featured a static Angular frontend distributed via CloudFront CDN for fast, globally cached delivery, backed by a Node.js API layer running on auto-scaled EC2 instances to handle variable order volumes.

A key technical challenge was building a robust print-material verification pipeline. I implemented an SQS-based workflow that validated uploaded PDF files against print specifications, integrated cloud-based virus scanning for all user-submitted content, and used Lambda functions for asynchronous background processing. User authentication and authorization were handled through AWS Cognito, providing secure, standards-based identity management.

DevOps

I joined Sanoma Media Finland's DevOps team at a pivotal moment — the organization had committed to migrating Oikotie Asunnot, one of Finland's largest real estate portals, from traditional on-premise hosting to the AWS cloud. I played a central role in planning and executing this migration, working to re-architect the platform's infrastructure for the elasticity, reliability, and cost efficiency that cloud hosting provides.

Beyond the migration effort, I was actively involved in developing and maintaining the Oikotie Asunnot platform itself, contributing to both the application layer and the operational tooling that kept the site running smoothly under high traffic. This role gave me a strong foundation in combining development and operations disciplines — an experience that has shaped my approach to infrastructure and platform engineering throughout my career.