A destination management company wanted to build a web-based reservation management system that would allow their staff based in different countries around the world to manage products & services that they offer and manage reservations for services that come from different sources. My Responsibilities: - Held several meetings with key stakeholders to gather requirements and specifications; - Worked with a UI designer to come up with UI templates for the functionality that they wanted; - Used PostgreSQL for the database, ExpressJS for the backend/API, and ReactJS for the front-end; - The application also required integrations with Booking.com, TripAdvisor, Hoteliga, AirBnb and Agoda. I built all the integrations through workflows using n8n; - Since the solution had to be web-based, accessible world-wide but still remain an internal system, I deployed it on their private cloud in AWS accessible only through a company VPN connection.

The company operates warehouses that support their ecommerce operations. They required an Android app that runs on the Zebra MC9400/MC9450 series devices that they use for scanning in the warehouses. The app would have to help them with daily warehouse management tasks and manage data in their central ERP database in SQL Server. My Responsibilities: My role was to design and develop the app. It includes common warehouse operations such as Receiving, Putaway, Stock Transfers, Cycle Counting, Picking, and Reporting. The arrangement of bins and locations within the warehouse influenced the design and setup, as it determined the order of locations during scan processes. I developed the front-end using .NET MAUI, focusing on high performance due to limited resources on Android devices. The backend was built as REST services with ASP.NET Web API, employing a microservices architecture to manage most of the application logic. I relied heavily on stored procedures written in T-SQL within the SQL Server database. The outcome was a highly responsive, efficient app that warehouse operators found very beneficial, as it helped to improve their productivity.

The client operates as an international corporate service provider and as such provides the services of incorporation and management of companies, trusts and foundations. They also register and license vessels in different jurisdictions. They have over 10,000 companies and 2,000 vessels under management and needed a data-driven application to keep track of everything. My Responsibilities: I served as a full stack engineer: - built the front end of the app in NextJS/React, and the backend included an API and job runners developed in C# with a PostgreSQL database. The app facilitated integration with the registrar for operations like incorporating companies and exchanging data to place orders for registrar services. This business environment operates under strict confidentiality and secrecy, so I had to implement numerous security features into the app to enhance security. It also featured an automated document generation system with a trained AI agent that produces documents from company data, based on templates provided by the user. This feature is particularly useful because the documents are based on verified legal templates and were previously generated manually, requiring legal verification before use. Now, the company only needs to verify the template beforehand, eliminating worries about user errors in the final document, resulting in faster document delivery!

The company sells clothes online through several marketplaces like Amazon, Allegro, Etsy and eBay. They also ship products through several carriers like DHL, UPS, FedEx, and RoyalMail. They required a central database that would manage the operations and be the single source of truth for all data relating to suppliers, products, inventory, warehousing, orders and shipments. The system had to be distributed, web-based, and feature integrations with all the aforementioned third parties. My Responsibilities: My role was to design and develop the app with the assistance of a UI Designer. - We conducted meetings with key stakeholders, gathering requirements and specific business workflows. - I divided the functionality into five modules: Purchasing, Warehousing, Sales, Shipping, and Reporting. While UI templates were being created, I developed the database; they preferred MS SQL. - I started the database design and backend development using ASP.NET Web API configured as microservices. I also initiated a job handler to manage integrations with third-party carriers, marketplaces, and suppliers. Following the UI templates from the designer, I built the application one module at a time using ASP.NET Blazor. - Once a module was ready for validation, I met with users, trained them, collected their feedback, and integrated it into the app. - Users were very satisfied with the final product due to the continuous communication and feedback cycle maintained during the development process.

The company operates an ecommerce business and required system that would allow them to quickly post products on several marketplaces, update inventory levels and price changes in real-time and also ship orders through several carriers. My Responsibilities: I served as a senior engineer on the project. After analysing their requirements, I decided to adopt a no-code, workflow-based approach as much as possible using n8n. There were instances where some coding tasks were necessary, mainly to handle parts that n8n could not perform on its own. Within one month, I built several workflows that enabled the company to list its products on Amazon, eBay, Rakuten, RealDE, Allegro, and Shopify, and they were able to ship via StallionExpress, TwoShip, UPS, USPS, DHL, ChitChat, FedEx, Globale, RoyalMail, and Passport. The company was very satisfied with the initial project and frequently contacts me to add more marketplaces and shipping carriers to their network.

The QuickBooks Desktop (QBD) API communicates with other apps over the SOAP protocol and uses the XML data format. The QuickBooks Online (QBO) API and the QuickBase API are both based on REST and uses JSON. The client required a SaaS solution to easily integrate QuickBase applications with the QBD and QBO accounting systems. My Responsibilities: I worked as a software engineer alongside a UI designer. - We created a simple, modern, and responsive UI to configure integration routes and map fields between QBO/QBD and QuickBase, and we designed reports for system monitoring. - I relied on QuickBase as the data store and primary UI, utilising custom CSS and Sencha Ext JS to support complex, dynamic field mappings and live reports. - QBO/QBD fields are fixed, with very limited options for customisation. QuickBase fields are highly adaptable. This required the field-mapping engine to be flexible enough to support various mapping configurations. - I also developed a backend for executing jobs that read each account's configuration and manage the data exchange between the three systems. I implemented this as a multi-threaded routine in C#, running on a Linux server. Multi-threading and parallel processing were essential to achieve high-speed data handling for each account. Quickbase eventually acquired this solution.