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Senior Application Developer

SystemDomain, Inc.United States🇺🇸United StatesPosted 7 Aug 2026

Quick Overview

Work Type
On Site
Level
Mid Senior

Job Description

Senior Application Developer - GenTax

Job Type: Contract

Location: Hybrid (Weekly Onsite Required)

Duration: Long-Term Contract

Position Overview

We are seeking a highly skilled Senior Application Developer with extensive experience supporting and enhancing enterprise GenTax applications. The ideal candidate will possess deep expertise in GenTax, C#, SQL, Visual Studio, and enterprise application integration technologies. This position is responsible for designing, developing, maintaining, and supporting mission-critical tax administration solutions while collaborating with business and technical stakeholders to deliver scalable, high-quality software solutions.

The successful candidate will play a key role throughout the Software Development Life Cycle (SDLC), including requirements analysis, application development, testing, deployment, system enhancements, and production support.

Key Responsibilities

  • Design, develop, enhance, and maintain enterprise applications within the GenTax platform.
  • Develop and optimize complex SQL queries, stored procedures, and database objects.
  • Design, develop, consume, and maintain RESTful and SOAP web services for enterprise integrations.
  • Collaborate with business users and stakeholders to gather, analyze, and document functional and technical requirements.
  • Translate business needs into scalable, maintainable technical solutions.
  • Perform application analysis, workflow design, and business process improvements.
  • Participate in application architecture, coding, testing, deployment, and production support activities.
  • Troubleshoot and resolve application, database, integration, and performance issues.
  • Conduct code reviews and ensure compliance with development standards and best practices.
  • Support software upgrades, version migrations, application enhancements, and data conversion activities.
  • Identify technical risks and recommend process and application improvements.
  • Mentor junior developers and provide technical guidance across development teams.
  • Collaborate with cross-functional teams throughout the Software Development Life Cycle (SDLC).
  • Prepare and maintain technical documentation, design specifications, and implementation guides.

Required Qualifications

  • Minimum 5 years of hands-on GenTax application development experience.
  • Strong proficiency in C#, SQL, and Visual Studio.
  • Experience designing, developing, and supporting RESTful and SOAP web services.
  • Strong experience gathering business requirements and preparing technical specifications.
  • Experience performing system analysis, workflow design, and business process implementation.
  • Excellent troubleshooting, debugging, and application support skills.
  • Strong understanding of enterprise application development methodologies and SDLC.
  • Excellent analytical, organizational, and problem-solving skills.
  • Strong written and verbal communication skills.
  • Ability to work independently while collaborating effectively with technical and business teams.

Preferred Qualifications

  • Experience supporting tax administration or revenue management systems.
  • Knowledge of government tax processing, motor vehicle registration, property tax, or related business processes.
  • Experience performing software upgrades, version migrations, and data conversion projects.
  • Experience providing technical leadership and mentoring development teams.
  • Knowledge of enterprise application architecture and integration patterns.
  • Experience working with Commercial Off-The-Shelf (COTS) enterprise applications.
  • Experience in Agile development environments.

Desired Skills

  • GenTax
  • C#
  • SQL
  • Visual Studio
  • REST API
  • SOAP Web Services
  • Application Development
  • System Analysis
  • SDLC
  • Database Development
  • Stored Procedures
  • Application Integration
  • Debugging
  • Software Upgrades
  • Data Conversion
  • Technical Documentation
  • Business Process Analysis
  • COTS Applications
  • Agile
  • Technical Leadership

Skills

SOAP
SQL
Agile
C#
REST

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