Senior Back-End Developer (Java / .NET Core)

CoSourcing Partners Inc.; Houston (TX); Hybrid; USD 120,000 - 160,000; Full time

Job summary

CoSourcing Partners Inc. is seeking a Senior Back-End Developer (Java / .NET Core) in Houston, TX, offering hybrid work with 3+ days onsite.

The role focuses on leading backend design, API development, and modernization from low-code platforms to robust, scalable services within a healthcare/diagnostics environment. You will mentor teammates and collaborate with data architecture to deliver reliable integrations, security, and performance in a regulated setting, with opportunity to shape the

Qualifications

• 8+ years of backend development experience.
• Strong hands-on with Java and .NET Core.
• Experience designing RESTful APIs and SQL Server tuning.
• Azure cloud experience and CI/CD practices.

Responsibilities

• Design, develop, and maintain back-end services and REST APIs using Java and .NET Core for internal applications.
• Lead the migration from low-code tools to scalable, API-backed backend solutions.
• Collaborate with data architecture to define back-end models and service boundaries.
• Mentor junior engineers and ensure documentation, testing, and production readiness.

Skills

Java

.NET Core

REST APIs

SQL Server

Azure

CI/CD

Docker

Git

Communication

Onsite 3 days/week

Job description

Senior Back-End Developer (Java / .NET Core)

• Houston, TX

Job Title: Senior Back-End Developer (Java / .NET Core)
Location: Houston, TX (Hybrid – 3+ days onsite)
Employment Type: Full-time, Direct Hire

About the Role

We are looking for a Senior Back-End Developer to join our internal Innovation & Software Development team in Houston. This role will lead the transition from low-code applications (PowerApps) to robust, custom-built solutions that streamline operations, improve efficiency, and support our growing healthcare/diagnostics environment. You will work closely with our Director of Innovation, data architecture team, and front-end developer to design and build backend services, APIs, and data-centric applications that support critical workflows - such as licensing, compliance, digital pathology, and internal automation. This is a hands-on, senior technical role with strong expectations for mentoring, collaboration, and impact in the first 90 days.

What You’ll Do (Key Responsibilities)

Platform & Application Development

• Design, develop, and maintain back-end services and REST APIs using Java and .NET Core, supporting internal web and data applications.
• Help lead the transition from Microsoft PowerApps and other low-code tools to custom, scalable applications backed by SQL Server and modern cloud services.
• Build reliable integrations between applications, databases, and analytics platforms (including SQL Server and Databricks).

Architecture & Modernization

• Collaborate with the Director of Data Architecture and data engineering team to define back-end architecture, data models, and service boundaries.
• Refine and evolve a primarily monolithic application landscape into a more modular, maintainable platform over time (no microservices today, but a modernization path ahead).
• Implement best practices for API design, error handling, logging, and security in a regulated, healthcare-oriented environment.

Collaboration & Mentorship

• Partner closely with a junior front-end developer to ensure clean, well-documented backend interfaces that support high-quality user experiences.
• Provide technical mentorship across the Innovation team, sharing patterns, code reviews, and guidance on design and implementation.
• Actively participate in design sessions, backlog grooming, and sprint planning, contributing both technical input and business context.

Operational Excellence

• Work with our managed IT partner (ECS) and internal teams to ensure solutions are secure, performant, and reliable within our infrastructure and cloud environment.
• Help establish and refine CI/CD pipelines using GitHub/GitLab and containerization tools (e.g., Docker) for consistent deployments.
• Contribute to technical documentation, system diagrams, and support hand-offs for production readiness.

What Success Looks Like (First 6–12 Months)

• Within 90 days, you have a deep understanding of our existing PowerApps and custom applications, and are contributing production-ready code to at least one high-impact system.
• Within 6 months, you have successfully led or significantly contributed to at least one migration from a low-code solution to a custom backend/API-backed application.
• Within 12 months, you are recognized as a go-to technical leader for backend decisions, mentoring the front-end developer and improving the overall quality, performance, and reliability of our applications.

Required Qualifications

• 8+ years of professional experience as a Back-End Developer / Software Engineer, with significant senior-level responsibilities.
• Strong hands-on expertise in Java and .NET Core for backend development.
• Proven experience designing and implementing RESTful APIs for internal or external applications.
• Solid experience with Microsoft SQL Server (schema design, stored procedures, performance tuning, query optimization).
• Experience working in a cloud environment, ideally Azure (App Services, hosting, identity, basic networking).
• Familiarity with modern development practices:
• Git-based version control (GitHub, GitLab, or similar)
• CI/CD pipelines
• Docker or other containerization tools
• Strong communication and collaboration skills, with experience working cross-functionally with product, data, and IT teams.
• Ability and willingness to work onsite in Houston at least 3 days per week.

Preferred Qualifications

• Experience in healthcare, life sciences, diagnostics, or other highly regulated industries (HIPAA, SOX, or similar).
• Exposure to Databricks or other modern data/analytics platforms.
• Experience working alongside or integrating with low-code platforms (e.g., PowerApps) and helping teams migrate away from them.
• Prior experience mentoring junior engineers or acting as a technical lead on projects.
• Familiarity with container orchestration and infrastructure-as-code (Kubernetes, Terraform, etc.), even if not used in the current environment

About the Team & Environment

• The Innovation team is a focused group (data architect, data engineer, analyst, PM, front-end dev, automation engineer) dedicated to building internal tools that eliminate manual work and improve efficiency.
• We are evolving from low-code, tactical solutions to more strategic, custom-built applications, and this role is central to that transformation.