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I am an experienced C#/.NET developer with a strong track record in designing, enhancing, and maintaining business-critical applications across government, financial, energy, defense, and private sectors. I focus on secure, high-quality software and use structured delivery, clear documentation, and transparent communication to align with both technical teams and stakeholders. In my day-to-day work I primarily use Visual Studio with Git and Azure DevOps (often set up and optimized CI/CD environments). I regularly take ownership in teams, strengthening code quality and maintainability through SOLID principles, automated testing (TDD), and practical improvements to development processes.…I am an experienced C#/.NET developer with a strong track record in designing, enhancing, and maintaining business-critical applications across government, financial, energy, defense, and private sectors. I focus on secure, high-quality software and use structured delivery, clear documentation, and transparent communication to align with both technical teams and stakeholders. In my day-to-day work I primarily use Visual Studio with Git and Azure DevOps (often set up and optimized CI/CD environments). I regularly take ownership in teams, strengthening code quality and maintainability through SOLID principles, automated testing (TDD), and practical improvements to development processes.

Wesley Jansen

Back-End Developer, Web Developer, Software Engineer, +2

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I am an experienced C#/.NET developer with a strong track record in designing, enhancing, and maintaining business-critical applications across government, financial, energy, defense, and private sectors. I focus on secure, high-quality software and use structured delivery, clear documentation, and transparent communication to align with both technical teams and stakeholders. In my day-to-day work I primarily use Visual Studio with Git and Azure DevOps (often set up and optimized CI/CD environments). I regularly take ownership in teams, strengthening code quality and maintainability through SOLID principles, automated testing (TDD), and practical improvements to development processes.…I am an experienced C#/.NET developer with a strong track record in designing, enhancing, and maintaining business-critical applications across government, financial, energy, defense, and private sectors. I focus on secure, high-quality software and use structured delivery, clear documentation, and transparent communication to align with both technical teams and stakeholders. In my day-to-day work I primarily use Visual Studio with Git and Azure DevOps (often set up and optimized CI/CD environments). I regularly take ownership in teams, strengthening code quality and maintainability through SOLID principles, automated testing (TDD), and practical improvements to development processes.

Available to hire

I am an experienced C#/.NET developer with a strong track record in designing, enhancing, and maintaining business-critical applications across government, financial, energy, defense, and private sectors. I focus on secure, high-quality software and use structured delivery, clear documentation, and transparent communication to align with both technical teams and stakeholders.

In my day-to-day work I primarily use Visual Studio with Git and Azure DevOps (often set up and optimized CI/CD environments). I regularly take ownership in teams, strengthening code quality and maintainability through SOLID principles, automated testing (TDD), and practical improvements to development processes.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Beginner

Language

Dutch

Fluent

English

Advanced

Work Experience

C#/.NET Developer at CIBG (Government sector)

March 1, 2025 - October 1, 2025

Worked in a development team expanding “Cobra”, an application within the BIG register. The application supports professional registrations, including manual and bulk registration processes for organizations with larger employee populations. Developed new functionality including API endpoints and Angular application pages. Focused on Test Driven Development and high-quality automated testing, and maintained related documentation in the team wiki within Azure DevOps. Contributed within a Scrum delivery context with emphasis on security, quality, and maintainable architecture.

C#/.NET Developer at Stedin (Energy sector)

February 1, 2024 - March 1, 2025

Maintained and further developed the Cryptex application, delivering new functionality and contributing to a renewed version using modern technologies. Helped strengthen the team’s Scrum practices through retrospectives and removal of bottlenecks. Aligned with client and product owner to refine requirements so the team could deliver efficiently. Developed new features and automated parts of the production release process, with strong focus on code quality, testing, CI/CD, and secure software development.

Lead C#/.NET Developer at Achmea (Financial sector)

July 1, 2023 - November 1, 2023

Assessed an archive system used by multiple Achmea subsidiaries, analyzing team maturity, technical baseline, and prerequisites for building a new archive system. Built on existing proof of concept and limited documentation. Aligned with managers, architects, and cloud/system administrators to confirm pending architectural decisions and OpenShift as the preferred platform. Interviewed the intended development team and produced an advisory report outlining outstanding decisions, team situation, and solution directions. Delivered an initial setup enabling a developer to start working immediately in line with the desired approach.

C#/.NET Developer at UWV (Government sector)

February 1, 2022 - February 1, 2023

Worked on expanding and modernizing UWV’s application landscape, building new applications with additional functionality and modernizing existing ones using newer technologies. Introduced standards and structures into the development approach, emphasizing secure software development, coding standards, and maintainable architecture. Delivered presentations/knowledge sessions to support team adoption and coordinated with administrators and architects from design through operations.

C#/.NET Developer at Rabobank (Financial sector)

March 1, 2021 - February 1, 2022

Worked on RRP DM, an ETL-style application delivering data to De Nederlandsche Bank for regulatory reporting. Implemented SAML authentication and authorization. Set up Azure DevOps pipelines and release pipelines and ensured development/release processes met compliance requirements. Maintained a strong focus on security guidelines and coordinated regularly with different departments to support delivery and onboarding of new developers into the required processes.

C#/.NET Developer at HSB & Defence (Defence sector)

July 1, 2020 - October 1, 2020

Contributed to the NOMAD project at Defence/HSB, building a Voting Management System for election processes. Implemented authentication and authorization for different user types. Developed data management pages and created a separate export application for generating voting cards and voter lists in required file formats. Aligned with stakeholders on functional requirements, technical prerequisites, and hardware requirements to ensure the solution matched real-world operating context.

PHP Developer at HSB (Private sector)

October 1, 2019 - July 1, 2020

Independently implemented predefined functionality in existing applications, including technical analysis and targeted improvements. Worked with a document scanner for passports, visas, and identity documents; developed functionality to process scanner data, store it in the database/session, and expose it efficiently within the application. Updated the front end to display new data clearly. For another project, adapted the application to new user requirements and significantly improved performance.

C#/.NET Developer at UWV (Government sector)

July 1, 2018 - September 1, 2019

Part of a six-person team ensuring Java and .NET applications complied with predefined security requirements. Assessed how well applications met security requirements; when deviations were found, implemented targeted changes (including rewriting software/protocols, adjusting server configurations, and preparing/updating documentation). Contributed to improved security and maintainability across the application landscape, with emphasis on clear structure and precise execution.

C#/.NET Developer at Capgemini & Defence (Defence sector)

May 1, 2018 - June 1, 2018

Contributed to “Whiteflag”, an open communication channel for armed conflict designed to avoid dependency on a trusted third party and to enable encrypted or unencrypted messages recorded on a blockchain system. Developed production software components for encoding and decoding and contributed to technical design and overall coherence so that production software could work with other parts of the Whiteflag protocol.

Software Developer at Capgemini (Private sector)

March 1, 2018 - April 1, 2018

Developed a Hyperledger Fabric application concept for Rijkswaterstaat to encourage inland shipping vessels to comply with applicable rules. In the concept, skippers earned coins by demonstrating desired behavior on the inland waterway network, then exchanged coins for benefits. Contributed to system architecture, connecting multiple nodes, and documenting technical choices and system setup. Delivered a working Hyperledger Fabric network to store data across multiple systems using blockchain technology.

Java/Kotlin Developer at Capgemini (Private sector)

October 1, 2017 - March 1, 2018

Worked on a Corda platform template for Capgemini, focusing on documentation of technical choices and troubleshooting documentation. Developed a Corda application allowing different Corda nodes on separate machines to communicate through transactions, with an emphasis on protecting sensitive data.

C#/.NET Developer at DesignCloud (Private sector)

February 1, 2017 - August 1, 2017

Developed ready-to-use C#/.NET web applications for clients, including developing, configuring, and preparing Umbraco CMS-based web applications. Built integrations with external web services (Facebook, Twitter, Instagram) using REST and SOAP. Integrated front-end work into the CMS, extended systems with new functionality and data types, resolved client issues by analyzing limited/complex problem causes, and delivered solutions enabling clients to manage content and load third-party data in real time.