Sijmen Koffeman
Software Engineer at Sijmen Koffeman Informatica
Fundão, Castelo Branco, Portugal
Summary
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SeniorSijmen Koffeman is a pragmatic, hands-on software engineer with over 15 years’ experience building front- and back-end solutions—primarily in the .NET ecosystem—across the Netherlands, Israel and Portugal. He combines deep experience in application integration (early BizTalk/EAI work) with SQL-backed web development (ASP/ASP.NET/ASP.NET Core) and growing interest in Blazor and cloud CI/CD. Comfortable in roles from developer to CTO and technical advisor, he excels at architecture, requirements scoping, and keeping teams motivated through tough decisions. A frequent contributor to open-source (notably Orchard Core fixes and UI enhancements), he blends bug fixes and small UX improvements that improve stability and developer experience. Based in Fundão, Portugal, he brings a consultant’s focus on pragmatic, deliverable solutions and a knack for persisting until the problem is resolved.
9 years of coding experience
Portuguese, English, Dutch, Hebrew, German
Stackoverflow
160reputation
14kreached
4answers
2questions
Github Skills (12)
asp-net10
cms10
asp-net-core10
csharp10
orchard-core10
dotnet-core10
javascript8
blazor6
wpf6
single-page-application6
xaml6
openid-connect6
Programming languages (9)
Github contributions (5)
OrchardCMS/OrchardCore
Oct 2018 - Mar 2019
Orchard Core is an open-source modular and multi-tenant application framework built with ASP.NET Core, and a content management system (CMS) built on top of that framework.
Role in this project:
Back-end Developer
Back-end DeveloperContributions:1 review, 8 commits, 11 PRs in 5 months
Contributions summary:Sijmen contributed to the Orchard Core project by addressing several issues and implementing new features. They focused on fixing bugs related to content deployment and search functionality, ensuring the application's stability. The user also added a copy-to-clipboard button for the HTTP request event editor, enhancing the user interface. Additionally, the user made a small fix to the copy clipboard script, improving functionality.
cmstenantwcfc-sharporchard-core
psijkof/CultureInfos
May 2018 - Jun 2023
Simple example using builtin culture infos in .net core
Contributions:4 PRs, 3 pushes, 3 branches in 5 years 1 month
dotnetbuiltinnet-corecsharpdotnet-core
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