Backend .NET Engineer

Blueface Ltd; Philadelphia (Philadelphia County); On-site; USD 90,000 - 120,000; Full time

Job summary

Blueface Ltd is looking for a backend engineer to join Comcast’s technology team. You will be responsible for delivering across high-visibility program areas, owning .NET services from specifications to production code. Your role involves designing and maintaining backend services and APIs in C# / ASP.NET Core, while mentoring teammates and collaborating with other teams.

The ideal candidate will have 5–7 years of backend software development experience and strong communication skills.

Qualifications

• 5–7 years of professional backend software development experience.
• Strong proficiency in C# and the .NET stack.
• Experience designing REST APIs and working with relational databases.

Responsibilities

• Author and refine OpenSpec artifacts and implement them as the source of truth.
• Design, build, and maintain backend services and APIs in C# / ASP.NET Core.
• Use AI coding assistants effectively to accelerate delivery.

Skills

C#

ASP.NET Core

REST APIs

SQL

Entity Framework Core

CI/CD

Git

Azure

OpenSpec

Job description

Job Summary

As a backend engineer in Comcast’s technology team, you will deliver across three high‑visibility program areas: the Managed Enterprise Services (MES) suite, the CBA side of AIX, and the Digital Convergence initiative (CVG/MA360). You will own .NET services end‑to‑end—authoring specifications, building and operating production code, and mentoring teammates—within our spec‑driven development (SDD) workflow powered by OpenSpec and AI coding assistants.

Responsibilities

• Author and refine OpenSpec artifacts—including proposals, requirement specs, design notes, and task breakdowns—and implement them as the source of truth.
• Design, build, and maintain backend services and APIs in C# / ASP.NET Core, including data access with SQL and Entity Framework Core.
• Use AI coding assistants effectively, driven by approved specs, to accelerate delivery without sacrificing quality.
• Write automated tests and ship through CI/CD pipelines; support deployment and operation of services in the cloud.
• Review peers’ specifications and code, mentor less‑experienced engineers, and help mature the team’s SDD practice.
• Collaborate with product, QA, and other engineering teams to translate ambiguous requirements into precise, buildable specifications.
• Engage with Quality Assurance to verify that software meets technical specifications and delivers high‑quality, reliable applications.
• Troubleshoot and resolve complex technical issues in software applications and systems.
• Conduct analysis of system requirements and customize applications to ensure optimal functionality.
• Assist with the software update process for existing applications and roll‑outs of software releases.
• Conduct training sessions for operational staff to ensure effective use of internally developed applications.
• Perform other duties and responsibilities as assigned.

Required Qualifications

• 5–7 years of professional backend software development experience.
• Strong proficiency in C# and the .NET stack (ASP.NET Core Web API).
• Experience designing REST APIs and working with relational databases (SQL, EF Core).
• Working knowledge of CI/CD, automated testing, version control (Git), and at least one cloud platform (Azure preferred).
• Comfort with or strong aptitude for spec‑first / specification‑driven workflows; direct OpenSpec or comparable SDD experience is a plus.
• Strong collaboration and communication skills; able to handle ambiguity well, provide thoughtful code feedback, and actively support and mentor teammates.
• Experience with AI‑native development tools such as OpenSpec or comparable frameworks (e.g., GitHub Spec Kit).

Employees at all levels are expected to:

• Understand and apply Comcast’s Operating Principles.
• Own the customer experience, think and act with the customer first.
• Be enthusiastic learners, advocates of technology and products.
• Work collaboratively as a team.
• Support a culture of inclusion and do what’s right for employees, customers, investors, and communities.
• Participate in the Net Promoter System to gather feedback and improve customer outcomes.

Equal Opportunity Statement

Comcast is an equal opportunity workplace. We will consider all qualified applicants for employment without regard to race, color, religion, age, sex, sexual orientation, gender identity, national origin, disability, veteran status, genetic information, or any other basis protected by applicable law.

For additional benefits information, please visit our careers site.