Senior Architect / C# / Greenfield

Motion Recruitment; Boulder (CO); Hybrid; USD 140,000 - 180,000; Full time

Job summary

Motion Recruitment in Boulder, CO is seeking a Senior Software Architect to join our engineering team in a hybrid setup with three onsite days per week. You will help build SaaS products using C#, .NET, SQL Server, and modern development practices, collaborating with experienced founders and a small, highly collaborative team to unify business operations into a single intelligent platform.

You will own architecture and design, contribute to technical planning, and work across the platform, from

Qualifications

• 7+ years of software development experience.
• Strong object-oriented programming fundamentals.
• Experience with C# and .NET ecosystem.

Responsibilities

• Design and implement software architecture across multiple components.
• Lead technical decisions and best practices.
• Collaborate with founders and a small team to deliver a unified platform.

Skills

C#

.NET ecosystem

Architecture

SOLID principles

OOP fundamentals

SQL Server

Database design

Requirements translation

Problem solving

Independent work

Communication

Education

7+ years of professional software development experience

Tools

WinForms

WPF

Wisej.NET UI

Job description

A growing software startup is seeking a Senior Software Architect to join its engineering team in Boulder, Colorado, working in a hybrid environment with three onsite days per week. This full-time opportunity offers the chance to help build SaaS productsusing C#, .NET, SQL Server, and modern development practices. Working alongside experienced founders and a small, highly collaborative team, you'll play a key role in designing and developing a product intended to unify business operations into a single intelligent platform.

The team is looking for someone who thrives when given a problem to solve rather than a step-by-step set of instructions. You'll be trusted to take ownership of features, explore solutions independently, and contribute to key technical decisions in an environment that values initiative and accountability. From application architecture and database design to feature development and technical planning, this role offers the opportunity to work across multiple areas of the platform while helping shape the future of a growing company.

Required Skills & Experience

• 7+ years of professional software development experience
• Strong expertise with C# and the .NET ecosystem
• Experience designing and building applications from the ground up
• Strong object-oriented programming fundamentals
• Deep understanding of SOLID principles and modern design patterns
• Experience with inheritance, composition, interfaces, and abstraction layers
• Strong SQL Server development experience
• Experience with database design, entity modeling, indexes, and constraints
• Experience translating business requirements into technical solutions
• Strong problem-solving and solution-design skills
• Ability to work independently with minimal direction
• Excellent written and verbal communication skills

Desired Skills & Experience

• WinForms or WPF development experience
• Startup experience
• Greenfield or build-from-scratch development experience
• Experience with Repository, Factory, Strategy, Observer, and Dependency Injection patterns
• Experience building workflow, project management, or enterprise software platforms
• Experience evaluating architectural tradeoffs and technology choices
• Experience working closely with executive leadership and product stakeholders
• Experience mentoring or guiding other developers

What You Will Be Doing

Tech Breakdown

• 50% C#/.NET Development
• 20% Software Architecture & Solution Design
• 20% SQL Server & Data Modeling
• 10% Wisej.NET UI Development

Daily Responsibilities

• 75% Hands-On Development
• 15% Architecture & Technical Design
• 10% Team Collaboration

Applicants must be currently authorized to work in the US on a full-time basis now and in the future.