Mariusz – Node.js, React, Typescript

This is an all-in-one platform that helps users create more sustainable packaging quickly and at scale. Users can design the packaging online in minutes or collaborate with experts to develop a bespoke solution.

• Designed and implemented product configurator for ecommerce basket (next.js + react.js);
• Architected and implemented an integrated stock-management system, unifying various spreadsheets and web apps into one comprehensive platform, driving 55% of company revenue and optimizing operations;
• Spearheaded the creation of an innovative greenfield platform, designed and developed with micro-frontends to enable seamless team collaboration, which improved operational efficiency and client satisfaction, establishing the platform as the default offering for all client interactions;
• Implemented a cross-application passwordless and SSO solution, enhancing security and accessibility across all enterprise applications;
• Transformed the hiring process by refining interview practices and standardizing questions;
• Provided engineers with the support, guidance, and mentorship to advance their careers, resulting in the promotion of two engineers to senior positions;
• Established coding standards and best practices, conducting regular code reviews and knowledge-sharing sessions;
• Led several POCs on integrating LLMs to automate the extraction of data from supplier orders in PDF format;
• Led implementation of the supplier quotes uploader using Next.js and Postgres.

This is a platform for Real Estate Agents to gain unique access to leads based on signals coming from the market on who are willing to sell and establish custom outreach channels on LinkedIn on behalf of agents. It has involved custom API integrations with data sources (planning applications, land registry, company houses, and various property listing pages) and setting up MVP for agents to use and gain access to leads.

• Used LLM (OpenAI) for conversation classification and automated tagging;
• Designed and scaffolded MVP;
• Provided web scrapping solution for obtaining data from public sources on property listings;
• Integrated firebase auth with react SPA;
• Designed and scaffolded async flows in Inngest;
• Designed DB schema;
• Integrated application with different source providers (land registry, heyreach.io, overlead.io, LinkedIn, Slack, etc.);
• Set up CI/CD and deployed on Cloudrun on gcloud and Vercel;
• Added monitoring and observability (sentry.io).

Proximie is a technology platform that allows clinicians to virtually ‘scrub in’ to any operating room or cath lab from anywhere in the world. The target audience is surgeons, hospital coordinators, health professionals, and medical students. The app consists of 2 client-facing single-page apps: the dashboard app and the live app.

• Was responsible for leading a "dashboard" team of 6 software engineers to deliver the solution;
• Helped to grow the team members, organized show & tell sessions and OKRs reviews;
• Implemented an 0Auth invite-only flow integration and turned off the standard registration as only hospitals and unis were allowed to invite trusted users;
• Implemented 0Authauth management API integration to allow managing users and organizations;
• Wrote unit & integration tests;
• Implemented cypress e2e tests, including 0Auth login flow + user journeys;
• Improved Devex, including local development: DB seeds, CLI commands, and debugging solutions.

Main achievement:

• As this industry was highly regulated by HIPAA compliant, data had to be stored in the location where the existing session/organization, so Mariusz was involved in designing multi-region data center architecture for providing a de-identified data storage solution - imagine a central server hosting non-PII in central location and store reference to data in data stores in satellite locations, the challenge was to marry up those data in the dashboard and get accurate PII in the runtime performance, and fallbacks.

Nationwide Building Society is a building society owned by its members. Anyone who banks, saves, or has a mortgage with them. They run for members' benefit and help the communities around them. The app Mariusz worked under was for mortgage brokers to make the process of streamlining mortgages easier, including all its stages and integration with banking services using event-driven architecture.

Main responsibilities:

• Developed several features of mortgage application single page application, using React.js, React-Router v4, Context API, SignalR, Axios, Formik, Semantic-UI, NBS-UI Library, Jest;
• Worked effectively with UI/UX designers producing high-quality prototypes using storybook and invasion;
• Created and maintained shared components and themes of internal UI library (NBS-UI), using React.js, Semantic-UI, Storybook, Jest
• Helped develop node.js CLI tool to speed up BDD testing;
• Assisted in Jenkins pipelines setup, maintained and monitored Kubernetes microservices using EFK stack;
• Worked in cooperation with .NET engineers pioneering implementation of Event Driven Architecture at Nationwide Building Society;
• Mentored Technology Development Programme graduates, enabling them to gain real-world experience.
• Worked on C#/.net microservices (affordability-checker, eligibility-checker, message-service, api gateway)

Main accomplishment:

• Worked on first market mortgage product for over 55s from service design to live in 10 months;

HT2Labs help learning and development get brighter through data. Mariusz developed and maintained the GDPR application, which allowed clients to stay compliant with EU law regulations.

Main tasks:

• Created front-end and backend architecture;
• Dockerized solution;
• Implemented CI/CD pipelines;
• Set up infrastructure including MYSQL DB;
• Wrote unit, integration, and e2e tests.

Mariusz has created a multi-threaded CLI tool in Java to import 16GB CSV files (Experian data) into a local database used for marketing purposes.

• Implemented CLI app using java and 4 threads concurrency;
• Designed and implemented DB schema (migrations)
• Maintained the app over time according to the new requirements