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

Senior Full Stack Developer

Confidential Careers

Senior Full Stack Developer - C#/.NET -Long Island, NY

Our client, a well-established financial services organization on Long Island , is investing heavily in a major technology modernization initiative and is looking for a Senior Full Stack Developer to join the team.

What You'll Do:

  • Develop and modernize enterprise applications using C#/.NET
  • Help transition legacy VB.NET applications to modern .NET architecture
  • Work extensively with SQL Server and complex relational databases
  • Leverage AI coding tools such as Claude and Microsoft Copilot to accelerate development and improve code quality

What We're Looking For:

  • Senior-level C#/.NET Full Stack development experience
  • Expert-level SQL Server skills
  • Experience modernizing legacy applications
  • Current hands-on experience with AI-assisted coding/development tools
  • Strong problem-solving skills and the ability to work across the full technology stack

This is an opportunity to join a stable, highly respected financial services firm while working on meaningful modernization initiatives and the next generation of software development.

Vacancy posted 2 days ago
Similar jobs that could be interesting for youBased on the Senior Full Stack Developer in Smithtown, NY vacancy
  • Senior Embedded Linux Engineer | Long Island, NY (On-site) | C2C / W2 / PermanentX4 Technology...  ...and customizing embedded Linux images, developing kernel-level and application-level...  ...supporting system integrationWorking across the full stack from bootloader to user-space... 
    Senior
    Permanent employment
    Local area
    Relocation
    Flexible hours

    X4 Technology

    Brentwood, NY
    1 day ago
  • Citi's Retail Mortgage team in Commack, NY seeks a Mortgage Lending Officer to originate high-quality residential real estate loans and serve clients through a highly interactive network of branches, operations and referral partners. The role requires 5-8 years in residential...
    Senior

    Citigroup Inc

    Commack, NY
    3 days ago
  • Medical Assistant LeadLeads and guides Medical Assistants in the performance of duties. Administers para-professional nursing care. Duties include, but are not limited to, preparing patient for physician and administering and/or recording laboratory tests. Assists in coordinating...
    Senior
    Hourly pay

    FlexStaff Careers

    Commack, NY
    19 hours ago
  • Parker Hannifin Corporation in Smithtown, NY, is seeking a skilled assembler to accurately and efficiently assemble and test complex products. Candidates should have seven or more years of relevant experience, with strong knowledge of electronics and the ability to work...
    Senior

    Parker

    Smithtown, NY
    8 hours ago
  • Sunrise Senior Living in New York is seeking an LPN Medication Nurse to provide licensed nursing support through safe medication administration, health monitoring, and accurate clinical documentation. You will follow the Six Rights of Medication Administration and document... 
    Senior

    Sunrise Senior Living

    Central Islip, NY
    1 day ago
  • St. James Rehabilitation & Healthcare Center is seeking a Recreation Therapist to join our growing team. The Recreation Therapist will plan and conduct group and individual recreation programs, document attendance, facilitate activities for residents, and assist with transport...
    Senior

    CareRite Centers, LLC

    Saint James, NY
    3 days ago
  • Heatherwood Communities is seeking a Sr. Maintenance Manager to lead the maintenance operations across multiple properties. This role emphasizes delivering exceptional service, maintaining safety standards, and ensuring operational consistency in a fast-paced environment...
    Senior

    Heatherwood Communities

    Central Islip, NY
    1 day ago
  • $70k - $85k

    A legal firm in Hauppauge is seeking a skilled professional to handle drafting pleadings, preparing trial documents, and managing discovery processes. The ideal candidate will oversee various legal documents and workflows within a dynamic team, contributing to the success...
    Senior

    Matrimonial and Family Law Firm

    Hauppauge, NY
    1 day ago
  • Parker Hannifin in Hauppauge, NY is looking for a skilled technician to accurately assemble, test, and troubleshoot complex products while maintaining high standards of quality and productivity. Applicants must have a solid background in AC/DC electronics and at least seven...
    Senior

    Parker

    Hauppauge, NY
    8 hours ago
  •  ...Tax Senior Overview The Tax Senior role offers an opportunity to contribute to tax compliance and advisory services for a diverse...  ...optimization. Analyze financial data to assess tax implications and develop strategic solutions. Collaborate with internal teams to... 
    Senior

    Green Key Resources

    Hauppauge, NY
    2 days ago
  •  ...along with employee benefits package. Responsibilities Developing project schedules and timelines Analyze and review construction...  ...work experience accepted Previous construction and full time estimating experience needed Strong computer skills (Bluebeam... 
    Senior
    Full time
    Work experience placement
    For subcontractor

    PRI Technology

    Central Islip, NY
    6 days ago
  • $90k - $100k

     ...Senior Network EngineerThe Senior Network Engineer will be required to develop solutions for complex network and server problems. They will have the ability to analyze existing systems and make proactive recommendations for improvements. Develops, maintains, and implements... 
    Senior
    Work at office
    Remote work

    NAKA Tech

    Hauppauge, NY
    3 days ago
  • Phoenix House is seeking a Licensed Clinician to lead clinical quality, support staff development, and influence client outcomes. The role blends clinical expertise with leadership across a multidisciplinary team to shape treatment journeys and ensure compassionate care...
    Senior

    Phoenix House

    Brentwood, NY
    1 day ago
  •  ...-Time Speech-Language Pathologist to evaluate, diagnose, and treat residents with communication and swallowing disorders. You will develop targeted treatment plans, provide communication instruction, monitor progress, and maintain comprehensive records while ensuring compliance... 
    Senior
    Part time

    Mills Pond Rehabilitation & Nursing Center

    Saint James, NY
    19 hours ago
  • Ayala, Morgan & Buzzard in Brentwood, CA is seeking a skilled paralegal to support our growing legal team. The ideal candidate will prepare and maintain legal documents, file motions, interview clients, and conduct legal research under guidance of an attorney. Responsibilities...
    Senior

    Ayala, Morgan & Buzzard

    Brentwood, NY
    1 day ago
  • A leading IT services company is seeking a proactive Accountant to manage day-to-day accounting operations and support financial growth. The role involves managing journal entries, overseeing billing and invoicing, and supporting month-end close processes. Ideal candidates...
    Senior
    3 days per week

    iStaff

    Hauppauge, NY
    1 day ago
  • Basaran Grinder Corporation in Hauppauge, NY seeks a senior machine assembly lead to drive complex builds, alignment, and process standards on-site. You will oversee first-builds, signoff criteria, and training, ensuring precision while scaling output. The role offers... 
    Senior
    Hourly pay

    Basaran Grinder Corp.

    Hauppauge, NY
    4 days ago
  • Phoenix House is seeking a Licensed Clinician in Hauppauge, NY to lead clinical services, elevate care quality, and influence client outcomes across the treatment continuum. This role blends clinical expertise with leadership, coaching, and coordination in a multidisciplinary...
    Senior

    Phoenix House

    Hauppauge, NY
    19 hours ago
  • $100k - $135k

    Litigation Bureau Attorney Position The Suffolk County Attorney's Office is seeking to hire attorneys for its Litigation Bureau. Key Responsibilities: Attorneys in the Bureau handle the defense of civil lawsuits against the County, all County agencies, departments...
    Senior
    Work at office
    Remote work
    Relocation package
    Monday to Friday

    Suffolk County

    Hauppauge, NY
    19 hours ago
  • Basaran Grinder Corporation seeks a senior builder to own the mechanical build of a complete CNC grinding machine from...  ...difficult fit and alignment problems, and mentors developing assemblers. You will lead the full assembly process with a focus on precise geometry and... 
    Senior

    Basaran Grinder Corp.

    Hauppauge, NY
    4 days ago
  • Job Description Job Description * Prepare Financial Statements; * Effectively plan and manage audit test work; * Proficient with generally accepted auditing standards and common audit procedures and techniques; * Proficient with GAAP or specialized accounting ...
    Senior
    Local area

    R.S. Abrams & Co., LLP

    Islandia, NY
    2 days ago
  • A leading aerospace manufacturer is seeking a Senior Machinist with significant CNC operation and setup experience. You will be responsible for setting up and operating multi-axis CNC equipment, interpreting engineering drawings, and validating new programs. The ideal... 
    Senior
    Hourly pay

    Innovative Rocket Technologies Inc.

    Hauppauge, NY
    1 day ago
  • Lane Valente Industries is a Leading International construction and facility maintenance company with offices across the U.S. and Canada. We are seeking an Automatic Door Service Technician to service a variety of automatic and manual doors, with AAADM certification preferred...
    Senior

    Lane Valente Industries

    Smithtown, NY
    1 day ago
  • $26.6 - $40.15 per hour

    A leading manufacturing firm seeks an experienced assembly/test professional in Smithtown, NY. The role involves assembling and testing products, troubleshooting issues, and using various mechanical processes. Candidates need at least five years in a similar field, strong...
    Senior

    Parker

    Smithtown, NY
    9 hours ago
  • Parker Hannifin is seeking an experienced assembly/test technician in New York. You will assemble and test moderate to semi-complex products, set up test stands, and use LabVIEW to capture data. You’ll troubleshoot, repair, and ensure quality while following lean initiatives...
    Senior

    Parker

    Smithtown, NY
    1 day ago
  •  ...specifications. The role requires pride in your craft, a solid understanding of color and print quality, and the ability to thrive in a fast-paced manufacturing environment. Shifts available: 2nd and 3rd, with competitive pay and full benefits. #J-18808-Ljbffr Oliver, Inc.
    Senior
    Shift work

    Oliver, Inc.

    Hauppauge, NY
    2 days ago
  • Stony Brook Eastern Long Island Hospital is seeking a Sr HR Generalist to support HR departments across multiple locations. The role focuses on compensation management, ensuring compliance with NYS Pay Transparency Law and maintaining equity. The ideal candidate will have...
    Senior

    Stony Brook Eastern Long Island Hospital

    Commack, NY
    19 hours ago
  • Hyde Park Mouldings, Inc. is seeking an experienced CAD Draftsperson to join our drafting department at 110 Kennedy Drive, Hauppauge, NY. The role focuses on producing detailed shop drawings for custom architectural products, using AutoCAD 2D and related tools, under tight...
    Senior

    Hyde Park Mouldings, Inc.

    Hauppauge, NY
    1 day ago
  • $100k - $110k

     ...Job Description Broadridge is hiring! We are seeking a Senior Business Analyst to manage fund and ETF proxy campaigns and help clients...  ...data-driven recommendations. Responsibilities Develop and adjust solicitation strategies using shareholder ownership... 
    Senior

    Broadridge

    Brentwood, NY
    26 days ago
  • Parker Aerospace is seeking a Quality Technician to support factory operations by monitoring inbound supplier products, resolving nonconformances, and ensuring part availability for Manufacturing Operations. You will escalate as needed and collaborate with internal teams...
    Senior

    Parker

    Smithtown, NY
    1 day ago

Do you want to receive more vacancies?

Subscribe and receive similar vacancies to Senior Full Stack Developer. Be the first to apply!