Sign up to access all features of our service.
  • Job search
  • Favorites
  • Create a CV
    New
  • Salaries
  • Subscriptions

Software Engineer (C#) - Internal Tooling

Alignerr

Software Engineer (C#) — Internal Tooling (AI Infrastructure)

What if your C# expertise could directly shape the infrastructure powering the world's most advanced AI systems? We're looking for experienced C# full-stack engineers to build and optimize the data pipelines, annotation tooling, and evaluation systems that leading AI labs depend on.

This is a fully remote contract role with meaningful technical scope — real production systems, high-impact workflows, and the kind of engineering problems that actually stretch your skills.

Organization: Alignerr

Type: Hourly Contract

Location: Remote

Commitment: 20–40 hours/week

What You'll Do
  • Design, build, and optimize high-performance C# systems supporting AI data pipelines and evaluation workflows
  • Develop full-stack tooling and backend services for large-scale data annotation, validation, and quality control
  • Improve reliability, performance, and safety across existing C# codebases
  • Collaborate with data, research, and engineering teams to support model training and evaluation workflows
  • Identify bottlenecks and edge cases in data and system behavior, and implement scalable, production-ready fixes
  • Participate in synchronous design reviews and iterate on system architecture decisions with senior engineers
Who You Are
  • Native or fluent English speaker with clear written and verbal communication skills
  • Full-stack developer with a strong systems programming background
  • 3–5+ years of professional experience writing production-grade C#
  • Experienced in interoperability scenarios — such as invoking Python ML models from.NET or wrapping native libraries
  • Skilled at designing robust benchmarking and evaluation harnesses
  • Able to commit 20–40 hours per week consistently
Nice to Have
  • Prior experience with data annotation, data quality, or evaluation systems
  • Familiarity with AI/ML workflows, model training, or benchmarking pipelines
  • Experience with distributed systems or developer tooling
  • Background working directly with or alongside AI research teams
Why Join Us
  • Work on cutting-edge AI infrastructure alongside leading research labs
  • Fully remote and flexible — work from wherever you do your best engineering
  • Freelance autonomy with the structure and consistency of ongoing, meaningful project work
  • Tackle genuinely hard technical problems with real-world impact on AI systems at scale
  • Potential for ongoing work and contract extension as new projects launch

Apply now

Vacancy posted 1 day ago
Similar jobs that could be interesting for youBased on the Software Engineer (C#) - Internal Tooling in United States vacancy
  •  ...Software Engineer (C#) - Internal Tooling (AI Infrastructure) About the Role What if your C# expertise could directly shape the infrastructure powering the world's most advanced AI systems? We're looking for experienced C# full-stack engineers to build and optimize... 
    Suggested
    Hourly pay
    Ongoing contract
    Contract work
    Freelance
    Remote work
    Flexible hours

    Alignerr

    New York, NY
    2 days ago
  • $20 - $71 per hour

    Software Engineering Intern, AI Tools - Fall 2026 page is loaded## Software Engineering Intern, AI Tools - Fall 2026locations: US, CA, Santa Claratime type...  ...in at least one programming language such as C, C++, C#, Java, or Python (Python preferred)* Experience with writing... 
    Suggested
    Hourly pay
    Internship

    NVIDIA Corporation

    Santa Clara, CA
    4 days ago
  • $66.3k - $70k

     ...Schedule: 9:00 am – 5:30 pm, Monday - Friday Compensation: $66,300 - $70,000 annually DOE Role The Software Developer/IT – Internal Tools will take full ownership of an internally built business application that powers key operational workflows at Gamer... 
    Suggested
    Local area
    Monday to Friday

    Gamer's Choice

    New York, NY
    17 days ago
  • $216k - $270k

     ...Scale AI is hiring a highly skilled Senior Software Engineer to help design, build, and operate...  ...applications, slackbots, and dashboards for internal users, and streamline complex workflows...  ...work with your team to build amazing tools/applications for internal company use... 
    Suggested
    Full time
    Work experience placement

    Scale AI

    San Francisco, CA
    1 day ago
  • $107.36k - $182.51k

     ...Software Engineer Because this role involves a combination of collaborative/in-person and independent work, it will take the form of...  ...eye for efficiency and enjoy tackling unique problems? The Internal Tools team is a multi-skilled development team looking for a talented... 
    Suggested
    Full time
    Work experience placement
    Local area
    Remote work
    Flexible hours

    BAE Systems USA

    Cedar Rapids, IA
    1 day ago
  •  ...infrastructure, and seamless developer tooling, we enable companies operating...  ...and help build the platform engineers turn to to ship AI products. THE ROLE: As a Software Engineer at Baseten, you will...  ...experience for customers and internal teams. Partner closely with... 
    Flexible hours

    Baseten

    New York, NY
    1 day ago
  • Software Engineer, Internal Tools Metriport is an open-source data intelligence platform that helps healthcare organizations access and exchange patient data in real-time. We integrate with all major US healthcare IT systems and tap into comprehensive medical data for... 
    Work at office
    Local area
    Remote work
    Work from home
    Relocation
    Flexible hours

    Metriport Inc

    San Francisco, CA
    1 day ago
  •  ...C++ Developer - Internal Tooling & Optimization What if your C++ expertise could directly shape the infrastructure powering the next generation of AI? We're looking for senior-level C++ engineers to design, build, and optimize the high-performance systems that leading... 
    Hourly pay
    Ongoing contract
    Contract work
    Freelance
    Remote work
    Flexible hours

    Alignerr

    United States
    1 day ago
  •  ...C++ Developer - Internal Tooling & Optimization (AI Infrastructure) About the Role What if your C++ expertise could directly shape...  ...advanced AI systems? We're looking for a Senior C++ Full-Stack Engineer to build and optimize the high-performance tooling, data... 
    Hourly pay
    Ongoing contract
    Contract work
    Freelance
    Remote work
    Flexible hours

    Alignerr

    Denver, CO
    2 days ago
  •  ...C++ Developer - Internal Tooling & Optimization (AI Infrastructure) About the Role What if your C++ skills could directly shape the...  ...AI systems? We're looking for a Senior C++ Full-Stack Engineer to design, build, and optimize the high-performance tooling and... 
    Hourly pay
    Ongoing contract
    Contract work
    Freelance
    Remote work
    Flexible hours

    Alignerr

    Seattle, WA
    2 days ago
  •  ...C# Developer (Tools and Installers) Orlando, FL ThreatLocker® is a leader in endpoint...  ...to design, build, and maintain internal tools and software installers that support our products...  ...usability. You'll work closely with engineering, QA, and DevOps teams to develop... 
    Work at office

    ThreatLocker

    Orlando, FL
    3 days ago
  • Software Engineering Intern - Internal Lab Asset Tracking Tool You will be building a simple, internal web application to track lab assets including testers, stations, boards, and chips. Engineers will use the tool to check in / check out equipment, see where assets are... 
    Internship

    TetraMem Inc

    San Jose, CA
    1 day ago
  • Vital Lyfe is seeking a Software Engineering Intern to assist in building software for high-demand consumer hardware. The role involves improving internal tools, designing dashboards, and supporting backend systems. Ideal candidates should have strong programming fundamentals... 
    Internship

    Vital Lyfe

    Los Angeles, CA
    1 day ago
  • $150k - $250k

    Company David creates tools to increase muscle and decrease fat. Our first product is a protein bar. More broadly, David...  ...in North America and beyond. Roles & Responsibilities The Software Engineer, AI & Internal Tools will serve as one of the company's primary builders... 
    Full time
    Work at office

    David Protein

    New York, NY
    1 day ago
  • Gamers Choice in New York, NY is seeking a Software Developer for internal tools. You will maintain an AI-assisted codebase, implement enhancements based on feedback, and troubleshoot IT-related issues. The ideal candidate has 1-3 years of coding experience, strong troubleshooting... 

    Gamers Choice

    New York, NY
    2 days ago
  • $48.1k - $86.95k

    Leidos is seeking a Junior CEMA Software Engineer Intern in Lawton, OK. The role involves working closely with a software development team to create...  ...challenges. Responsibilities include developing cyber tools, collaborating on Agile Scrum teams, and emulating threat-representative... 
    Internship

    Leidos

    Norman, OK
    4 days ago
  • $48.1k - $86.95k

    Leidos is seeking a Junior CEMA Software Engineer Intern in Lawton, OK. This role involves supporting the development of cyber tools and simulations for defense. Candidates should be pursuing a relevant degree and possess experience in Python, C++, and Agile development... 
    Internship

    Leidos

    Edmond, OK
    4 days ago
  • Leidos is seeking a Junior CEMA Software Engineer Intern in Lawton, OK. This role involves supporting a development team in creating cyber tools and simulations for complex engineering challenges. Ideal candidates should be pursuing a Bachelor's or Master's degree in a... 
    Internship

    Leidos

    Oklahoma City, OK
    4 days ago
  • $216.2k - $270.25k

    Scale AI is hiring a highly skilled Senior Software Engineer to help design, build, and operate...  ...applications, slackbots, and dashboards for internal users, and streamline complex workflows...  ...work with your team to build amazing tools/applications for internal company use... 
    Work experience placement

    Scale AI, Inc.

    San Francisco, CA
    1 day ago
  • A leading technology startup in San Francisco is seeking a skilled Software Engineer to develop internal tools for machine learning workflows. The role involves enhancing pipelines for audio and text data ingestion while working closely with cross-functional teams. The... 

    Sesame

    San Francisco, CA
    3 days ago
  •  ...Meta, Google, and Apple, with deep expertise spanning hardware and software. Join us in shaping a future where computers truly come alive. About the Role As a Software Engineer building internal tools at Sesame, you will be building and maintaining the pipelines and tooling... 
    Full time
    Contract work
    Flexible hours

    Sesame

    San Francisco, CA
    3 days ago
  • $120k - $140k

    A leading provider of autonomous systems is seeking a Software Engineer, Internal Tools, in Clarksburg, Maryland. This role involves developing and maintaining tools for autonomous vehicle platforms. Candidates should have 3+ years of software engineering experience with... 

    Forterra

    Clarksburg, MD
    3 days ago
  •  ...contribute, grow, and make a lasting impact on industries that power the world's most dynamic markets. Job Title: Intern: Application Engineering Tools & Resource Catalog Location: Franklin, TN Reports To: Applications Engineering Program Manager About IEM... 
    Internship

    US - Industrial Electric Manufacturing

    Franklin, TN
    1 day ago
  • $30 - $35 per hour

     ...services firm is offering a project-focused internship for an AI engineer embedded on the DevOps team. The role involves designing and...  ..., collaborating with technology teams, and working on internal tooling projects. Candidates should be pursuing a degree in a relevant... 
    Hourly pay
    Internship

    Framework Ventures

    New York, NY
    2 days ago
  • $66.7k - $133.3k

     ...defense technology firm is seeking a Junior C# Software Engineer in Bethesda, Maryland, to design, develop, and maintain software tools for aircraft operational safety. The role...  ...,700 - $133,300 annually, with up to 10% travel expected. #J-18808-Ljbffr CACI International Inc

    CACI International Inc

    Bethesda, MD
    14 hours ago
  •  ...Schwab Corporation is seeking a Full Stack Engineer in Austin, TX. In this role, you will design and build scalable applications for internal users. Collaboration with cross-functional...  ...of experience using React, TypeScript, C#, and .NET Core. The position offers competitive... 

    Charles Schwab Corporation

    Austin, TX
    2 days ago
  • $147.4k - $220.9k

    A leading technology company in Sunnyvale, California, seeks a Software Application Support Engineer to troubleshoot and enhance internal tools. The ideal candidate has over 5 years of relevant experience and a solid foundation in Ruby on Rails and database management.... 

    Apple Inc.

    Sunnyvale, CA
    2 days ago
  • A leading AI research firm is seeking an IT Applications Engineer to enhance internal IT services using automation and development of internal tools. The role includes managing applications for identity and access management, designing dashboards, and creating Slack bot... 
    Work at office
    3 days per week

    Slope

    San Francisco, CA
    3 days ago
  • $66.7k - $133.3k

     ...based in Bethesda, Maryland, is seeking a Junior C# Software Engineer to design, develop, and maintain software tools that enhance the Navy's fleet readiness....  ...along with comprehensive benefits and a focus on continuous growth. #J-18808-Ljbffr CACI International Inc.

    CACI International Inc.

    Bethesda, MD
    2 days ago
  • $150k - $300k

    A leading venture capital firm is hiring an AI Engineering Lead in San Francisco. This unique role involves building internal tools and shaping AI strategy to improve effectiveness. The ideal candidate will be a product-minded engineer, proficient in designing and deploying... 

    Palermo Advisors

    San Francisco, CA
    2 days ago

Do you want to receive more vacancies?

Subscribe and receive similar vacancies to Software Engineer (C#) - Internal Tooling. Be the first to apply!