10/15/2026 updated
100 % available
Hands-on Software Architect | Principal Engineer | .NET & C#
Jirkov, Czech Republic
Only remote
Secondary School Diploma – ITAbout me
Hands-on Software Architect and C#/.NET Engineer with 20 years of experience in enterprise and e-commerce systems. I help clients modernize legacy applications, improve architecture and performance, review code, design APIs, and solve complex backend problems. Available remotely from Czechia.
ASP.NETX86 ArchitectureApplications ArchitectureASP.NET MVC FrameworkC Sharp (Programming Language)Client Server ModelsData ArchitectureE-CommerceEnterprise Architecture FrameworkHigh-Level ArchitectureIBM Systems Network ArchitectureLegacy System Migration WorkbenchMicrosoft SQL ServersPerformance EngineeringSoftware Architecture
Software Architecture & System Design
Expertise in software architecture, system design, modular monoliths, ADRs and architecture fitness tests. Long-term architectural ownership of business-critical platforms across multiple generations, with pragmatic, trade-off-driven decision-making.
Backend Development with .NET & C#
Deep proficiency in C#, .NET, ASP.NET Core, ASP.NET MVC, SQL Server and Dapper. Hands-on development of business-critical backend systems, including asynchronous processing, data layer modernization and stored procedures.
Legacy Modernization & Incremental Migration
Proven track record in legacy modernization using the Strangler Fig approach, incremental migration strategies and production-first thinking. Ability to stabilize poorly tested legacy code while keeping revenue-generating systems operational.
Web & API Development
Experience with Angular, AngularJS, GraphQL, JavaScript and SignalR for building modern web frontends and APIs, including founding and leading a new Angular frontend for a large-scale eCommerce platform.
Search & Elastic Stack
Initiation and design of Elasticsearch-based catalogue search and the supporting ELK stack, including nightly search-data preparation batches and knowledge transfer to reduce single-person dependencies.
Security & OWASP
Execution of OWASP ASVS-based production security audits with concrete remediation programs covering authentication, password storage, CSRF/CORS, webhook validation and secret handling.
Technical Leadership & Mentoring
Technical leadership, code review, mentoring of junior developers from onboarding to independent contribution, and serving as the regular technical and architectural point of contact for the team.
Architecture Documentation & ADRs
Documentation of significant architectural choices through ADRs and technical plans, explicitly comparing alternatives and trade-offs, and introduction of architecture fitness tests in CI.
Cloud & Azure
Familiarity with Azure and cloud concepts through exploration and selected services, though not presented as production Azure project experience.
Expertise in software architecture, system design, modular monoliths, ADRs and architecture fitness tests. Long-term architectural ownership of business-critical platforms across multiple generations, with pragmatic, trade-off-driven decision-making.
Backend Development with .NET & C#
Deep proficiency in C#, .NET, ASP.NET Core, ASP.NET MVC, SQL Server and Dapper. Hands-on development of business-critical backend systems, including asynchronous processing, data layer modernization and stored procedures.
Legacy Modernization & Incremental Migration
Proven track record in legacy modernization using the Strangler Fig approach, incremental migration strategies and production-first thinking. Ability to stabilize poorly tested legacy code while keeping revenue-generating systems operational.
Web & API Development
Experience with Angular, AngularJS, GraphQL, JavaScript and SignalR for building modern web frontends and APIs, including founding and leading a new Angular frontend for a large-scale eCommerce platform.
Search & Elastic Stack
Initiation and design of Elasticsearch-based catalogue search and the supporting ELK stack, including nightly search-data preparation batches and knowledge transfer to reduce single-person dependencies.
Security & OWASP
Execution of OWASP ASVS-based production security audits with concrete remediation programs covering authentication, password storage, CSRF/CORS, webhook validation and secret handling.
Technical Leadership & Mentoring
Technical leadership, code review, mentoring of junior developers from onboarding to independent contribution, and serving as the regular technical and architectural point of contact for the team.
Architecture Documentation & ADRs
Documentation of significant architectural choices through ADRs and technical plans, explicitly comparing alternatives and trade-offs, and introduction of architecture fitness tests in CI.
Cloud & Azure
Familiarity with Azure and cloud concepts through exploration and selected services, though not presented as production Azure project experience.
Experience
Professional experience10+ years
Freelancer since2007
Languages
EnglishFluent
Project history
Independent software architect and .NET/C# engineer working primarily on long-term software architecture and development engagements, alongside smaller projects for other clients. Primary long-term engagement: LKQ / Auto Kelly eCommerce Platform (2006/2007 - 2026). Designed and evolved a business-critical eCommerce platform used across five markets (CZ, SK, RO, UA, HU), covering spare-parts catalogue and ordering, service management, fleet management, content management, payments and integrations with ERP and external partner systems. Led the platform technical evolution through multiple generations while remaining hands-on with the code. Designed the target architecture for the next generation: a .NET 8 backend organized as a modular monolith with clearly separated domains and architecture tests enforcing module boundaries. Planned and executed incremental modernization using the Strangler Fig approach. Modernized critical backend paths, audited and modernized the data layer from ADO.NET toward Dapper, initiated Elasticsearch-based catalogue search, performed an OWASP ASVS-based production security audit, documented architectural choices through ADRs, and mentored three junior developers.
Software development in C#/.NET and ASP.NET, including work on a customer project for Hewlett-Packard. Technologies included C#, .NET Framework, ASP.NET and SQL.