Slaven Semper, Developer in Zagreb, Croatia
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Slaven Semper

Verified Expert  in Engineering

Software Architect and Developer

Location
Zagreb, Croatia
Toptal Member Since
October 11, 2022

Slaven has been passionate about technology and software development from his earliest days and won some awards, like first place in the American Computer Science League in 1996 in Washington, D.C. He was a team leader in NBMIS, a €5.25 million project involving 65 team members on 25 international border crossings with more than 640 pieces of hardware, such as ANPR cameras and mobile devices. Slaven has successfully led many teams to complete their projects in his 16-year professional career.

Portfolio

Sandstorm
Swift 5, Ethereum, Solidity, React, Analysis, HTML5, Swift, iOS, GitHub, Git...
Solvency II Wire Ltd
Front-end, JavaScript, User Experience (UX), User Interface (UI)...
Taqniat
.NET 4, SharePoint, HTML, JavaScript, AngularJS, Angular, CSS3, Sass...

Experience

Availability

Full-time

Preferred Environment

.NET 5, Angular, SQL Server 2017, Visual Studio 2016, HTML, Sass, CSS3, Web API 2, ASP.NET, Windows Services

The most amazing...

...project I worked on was a national border management information system, leading teams of seven members in a 65-member environment in Croatia and Spain.

Work Experience

Senior Full-stack Developer

2022 - PRESENT
Sandstorm
  • Developed a real-time strategy game on the Ethereum network. The front end was made in React using the OpenStreetMap API and Metamask API. The application was optimized due to the large number of objects displayed in a layer on top of the map.
  • Produced a feature set for the game and modified the settings to ensure that all features were mutually compatible.
  • Involved in strategic business decision-making, such as planning investments and hiring employees.
  • Managed a domain specialist, providing insight for ideas, resulting in features.
Technologies: Swift 5, Ethereum, Solidity, React, Analysis, HTML5, Swift, iOS, GitHub, Git, Front-end, Full-stack, Python, API Integration, JSON, JSON REST APIs, .NET Core, OAuth 2, Mobile Apps, Maps, MacOS, Debugging, Databases, System Administration, Requirements Analysis, Blockchain, Web3.js, Decentralized Finance (DeFi), Cryptocurrency, Smart Contracts, Bots, C#.NET, Development, Websites, Docker, Python 3, Leadership, Xcode, Swift 4, Front-end Development, Responsive UI, Web, Mobile Development, Web Applications, Mobile Applications, .NET 6, Web Development, Software Engineering, UI Development, UI Design, Angular, TypeScript, Project Management, IT Projects, Business Requirements, User Experience (UX), User Interface (UI), Software Design, JavaScript Libraries, Back-end, Scripting, Software Architecture, Virtual Machines, NPM, RESTful Web Services, Web Security, Crypto, Full-stack Development, Trading, OAuth, Semantic HTML, Bitbucket, Auth0, QR Codes, GitLab CI/CD, Cloud Services, Front-end Architecture, Microsoft Excel, Data Structures

Front-end Developer

2022 - 2023
Solvency II Wire Ltd
  • Developed an app that enables comparison and analysis of financial reports of insurance companies.
  • Tracked and fixed bugs using Jira as an issue tracker.
  • Provided a mechanism for migrating old technology forms to Angular templates.
Technologies: Front-end, JavaScript, User Experience (UX), User Interface (UI), Data Visualization, Angular, Chart.js, RxJS, Lottie, PDF.js, Figma, Virtual Machines, NPM, RESTful Web Services, Web Security, Charts, Graphs, Full-stack Development, SCSS, Semantic HTML, Cloud Services, Front-end Architecture, Microsoft Excel, Data Structures

Software Architect

2017 - 2021
Taqniat
  • Helped develop projects across multiple business domains, facilitating agile principles.
  • Tracked and fixed bugs using Team Foundation Server as an application lifecycle management tool.
  • Wrote technical documentation, providing expertise on security models, data structures, and other aspects of the system.
  • Headed a team consisting of a designer and developer by providing guidance and code reviews.
  • Handled a business analysis of the project by moderating meetings with multiple clients.
  • Architected system design by integrating technologies that best fit the business requirements and client's needs.
Technologies: .NET 4, SharePoint, HTML, JavaScript, AngularJS, Angular, CSS3, Sass, Windows Communication Foundation (WCF), Photoshop CS3, Team Leadership, Business Analysis, Oracle, SQL Server 2017, TypeScript, C#, Node.js, Microsoft Team Foundation Server, jQuery, APIs, CSS, Chart.js, Architecture, .NET, Analysis, Angular Material, Microsoft SQL Server, Content Management Systems (CMS), HTML5, RxJS, REST, REST APIs, Scrum, Front-end, Full-stack, Solution Architecture, SQL, Technical Writing, API Integration, JSON, JSON REST APIs, .NET Core, Linux, Windows, Windows Forms (WinForms), OAuth 2, Bootstrap, WebSockets, Debugging, Databases, System Administration, LAMP, Requirements Analysis, C#.NET, Development, Websites, Leadership, Technical Leadership, Front-end Development, Vanilla JS, Responsive UI, Software Architecture, Web, i18n, Multi-language Support, Windows Desktop Software, Desktop App Development, Web Applications, Agile Sprints, Web Development, Software Engineering, UI Development, UI Design, UX Design, Project Management, IT Projects, Business Requirements, User Experience (UX), User Interface (UI), Data Visualization, Agile, Software Design, JavaScript Libraries, Back-end, Scripting, DevOps, Document Management, Virtual Machines, Windows Server 2016, NPM, RESTful Web Services, Web Security, WCF Web Services, Content Writing, Writing & Editing, Windows PowerShell, Search Engine Optimization (SEO), Charts, Graphs, Dashboards, Full-stack Development, Monday.com, SCSS, Semantic HTML, Enterprise Architecture, Enterprise Business Architecture, Technical Architecture, C#.NET WinForms, Front-end Architecture, Microsoft Excel, Data Structures

System Architect

2008 - 2017
IN2
  • Worked as a team leader and a remote team leader on a project with 65 team members.
  • Tracked and fixed bugs using Jira and Team Foundation Server as reporting tools.
  • Helped develop 12 projects, primarily focusing on government entities.
  • Wrote technical offers and conducted pre-sales presentations.
  • Trained end-users on how to use newly developed software.
  • Wrote multi-level technical documents and user manuals.
Technologies: ASP.NET, Windows Services, Windows Communication Foundation (WCF), SharePoint, Windows Forms (WinForms), .NET 3, Document Design, System Design, Team Leadership, Remote Team Leadership, .NET Compact, HTML, jQuery, SQL Compact CE, Oracle, Business Analysis, .NET 4, SQLite, Entity Framework, APIs, CSS, MySQL, PostgreSQL, Architecture, .NET, Analysis, Azure, Microsoft SQL Server, Content Management Systems (CMS), HTML5, Microsoft Azure, REST, REST APIs, Scrum, Front-end, Full-stack, Solution Architecture, SQL, Technical Writing, SOAP, API Integration, JSON, JSON REST APIs, Microsoft Access, Windows, Windows Presentation Foundation (WPF), OAuth 2, SharePoint 365, Selenium, Web Scraping, Real-time Data, Web Crawlers, SharePoint Online, Office 365, Debugging, Unit Testing, Databases, Requirements Analysis, Single Sign-on (SSO), SAML-auth, C#.NET, Development, Websites, Leadership, Technical Leadership, Front-end Development, Vanilla JS, Software Architecture, Web, Windows Desktop Software, Desktop App Development, Web Applications, Mobile Applications, Agile Sprints, Web Development, MVC Design, Software Engineering, UI Development, UI Design, Project Management, IT Projects, Business Requirements, User Experience (UX), User Interface (UI), Agile, Software Design, Reporting, JavaScript Libraries, Back-end, Scripting, OCR, Test-driven Development (TDD), CI/CD Pipelines, LINQ, SQL Server DBA, DevOps, Document Management, Virtual Machines, Windows Server 2016, RESTful Web Services, Web Security, WCF Web Services, Content Writing, Writing & Editing, Online Payments, Windows PowerShell, Search Engine Optimization (SEO), Azure SQL, Full-stack Development, Semantic HTML, Enterprise Architecture, Enterprise Business Architecture, Technical Architecture, Cloud Services, C#.NET WinForms, Front-end Architecture, Microsoft Excel, Scalability, Data Structures

.NET Developer

2006 - 2008
M SAN Grupa
  • Developed an application to support the wholesale distribution of products.
  • Tracked and fixed bugs, developed new features, and trained users.
  • Made critical deployments in an environment with very costly downtime.
Technologies: Windows Forms (WinForms), Web Services, SQL Server 2008, C#, Visual Studio, .NET, Microsoft SQL Server, SQL, API Integration, Windows, Debugging, Databases, C#.NET, Development, Websites, Web, Windows Desktop Software, Desktop App Development, Web Applications, Web Development, Software Engineering, UI Development, IT Projects, Virtual Machines, C#.NET WinForms, Data Structures

National Border Management Information System

A .NET Compact app developed for a handheld device used by border police officers to handle train and airport border crossings. I was a team leader for a team in Croatia and a remote team leader for a team in Spain. This project was a high-budget project that included 65 team members at its peak.

ePassport

A Windows application for acquiring biometric data in issuing a new passport.

As the lead developer, I oversaw the development of the Windows application. I worked on all application modules, such as fingerprint acquisition, biometric image conversion to JPEG 2,000, and final verification of a new passport.

Revenue Administration Modernisation Project

https://www.porezna-uprava.hr/
A SharePoint web application displaying information to taxpayers. I developed a regulation module with advanced caching logic. This includes recursively traversing entities so that regulations load as quickly as possible.

Support to the Establishment of the Components of the Integrated Land Administration System (ILAS)

A SharePoint web application that supports business processes of handling second-instance cases related to land administration. As the team leader on the project, I decided to introduce Workflow Manager technology to this project, which has since been reused in other projects. All business processes were modeled as workflows.

Healthcare Web Application

An HTML/jQuery/.NET/SQL Server web application for managing requests regarding healthcare services in the local county.

I was a web developer developing forms needed to manage requests created by end users. Local county employees would then take appropriate actions on demand.

Energy Market Regulation Web Application

An ASP.NET web application to support business processes for Croatian Energy Market Operator (HROTE).

I was a business analyst responsible for defining and understanding business processes in the Croatian energy market.

Forms Web Application

An ASP.NET 4.0/SQL Server web application for requests of local county users to local government. I was a team leader responsible for business analysis, leading a team, and developing the web application.

Person Register Web Application

An ASP.NET 2.0/Oracle web application for managing personal identification numbers and places of residence for the Ministry of Interior, Republic of Croatia.

I was a web developer responsible for implementing web pages.

Company Intranet Web Application

A company intranet web application based on Microsoft SharePoint 2007.

I was a web developer responsible for implementing/enabling out-of-the-box features and customizing the features to comply with business requirements.

Point of Sale Windows Application

A point of sale (POS) Windows application product to handle receipts.

I was a developer responsible for writing a Windows service to synchronize data between point of sale stations and the central system. Synchronization was bidirectional.

Languages

HTML, C#, TypeScript, JavaScript, CSS, HTML5, C#.NET, SCSS, Sass, CSS3, SQL, T-SQL (Transact-SQL), Semantic HTML, Solidity, Swift 5, Swift, C++, Python, Java, C, Python 3, Swift 4

Frameworks

Angular, ASP.NET, .NET 3, .NET 4, AngularJS, .NET, Angular Material, .NET Core, Vanilla JS, ASP.NET Web Forms, Windows PowerShell, .NET 5, .NET Compact, WWF, Windows Presentation Foundation (WPF), OAuth 2, Bootstrap, Selenium

Libraries/APIs

Entity Framework, Chart.js, LINQ, Windows Forms (WinForms), jQuery, React, REST APIs, Web API 2, Node.js, RxJS, Web3.js

Tools

Visual Studio 2010, Microsoft Team Foundation Server, Visual Studio, C#.NET WinForms, Microsoft Excel, Figma, NPM, Bitbucket, Auth0, Jira, Photoshop CS3, GitHub, Git, Microsoft Access, Apache, MATLAB, Xcode, Microsoft Visual C++, GitLab CI/CD

Paradigms

Scrum, Requirements Analysis, Desktop App Development, Agile, REST, MVC Design, Test-driven Development (TDD), DevOps, Search Engine Optimization (SEO), Unit Testing, Mobile Development, UI Design, UX Design

Platforms

Visual Studio 2016, SharePoint, Windows, Web, Windows Server 2016, SharePoint 365, Oracle, Ethereum, Azure, iOS, Linux, MacOS, LAMP, Blockchain, Docker, PDF.js

Storage

Microsoft SQL Server, Databases, SQL Server 2017, SQL Server 2008, SQLite, JSON, SQL Compact CE, MySQL, PostgreSQL, SQL Server DBA, SQL CE, Azure SQL

Other

Software Development, Algorithms, Software, APIs, Architecture, Content Management Systems (CMS), Front-end, Debugging, System Administration, Development, Websites, Front-end Development, Software Architecture, i18n, Multi-language Support, Windows Desktop Software, Web Applications, Agile Sprints, Web Development, Software Engineering, UI Development, IT Projects, Business Requirements, User Experience (UX), User Interface (UI), Data Visualization, Software Design, JavaScript Libraries, Back-end, Document Management, Virtual Machines, WCF Web Services, Content Writing, Writing & Editing, Charts, Graphs, Dashboards, Full-stack Development, Enterprise Architecture, Enterprise Business Architecture, Technical Architecture, Front-end Architecture, Data Structures, Windows Services, Web Services, Windows Communication Foundation (WCF), Analysis, System Design, Interactive JavaScript, Business Analysis, Full-stack, Solution Architecture, Technical Writing, API Integration, JSON REST APIs, SharePoint Online, Office 365, Leadership, Technical Leadership, Responsive UI, Mobile Applications, Reporting, Scripting, OCR, CI/CD Pipelines, 3D, RESTful Web Services, Web Security, Online Payments, Cloud Services, Scalability, Document Design, Team Leadership, Remote Team Leadership, Microsoft Azure, Multithreading, SOAP, Mobile Apps, Maps, WebSockets, Web Scraping, Real-time Data, Web Crawlers, Decentralized Finance (DeFi), Cryptocurrency, Smart Contracts, Bots, Single Sign-on (SSO), SAML-auth, Payment Gateways, .NET 6, Lottie, Crypto, Leadership Development, Monday.com, Trading, OAuth, QR Codes

Industry Expertise

Project Management

1999 - 2006

Master of Science Degree in Computer Science

University of Zagreb, Faculty of Electrical Engineering and Computing - Zagreb, Croatia

NOVEMBER 2015 - NOVEMBER 2017

MCSD: SharePoint Applications

Microsoft

SEPTEMBER 2014 - PRESENT

Microsoft Programming in HTML5 with JavaScript and CSS3

Microsoft

APRIL 2013 - PRESENT

MCTS: .NET Framework 4, Service Communication Applications

Microsoft

APRIL 2013 - PRESENT

MCPS: Microsoft Certified Professional

Microsoft

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