Fullsteam · 1 day ago
Senior Developer
Fullsteam is a leading provider of vertical software and embedded payments technology dedicated to helping businesses flourish. They are seeking an experienced Full-Stack Engineer to own features end-to-end across a diverse technology stack, including ASP.NET webforms and backend services, while managing key products such as Webpay, SMS, and IVR.
PaymentsSoftware
Responsibilities
Own features end-to-end — from technical design and implementation to testing, deployment, and observability — across ASP.NET Webforms, ASP.NET backend, WCF APIs, VB6, and data layers
Troubleshoot and resolve integration issues with other software
Collaborate with support and sales to deliver bug resolution, new features, and functionality changes
Manage Webpay, SMS, ACM (Automated Collections Module), IVR and desktop products
Design and integrate APIs (REST): write clear contracts, handle auth, rate limiting, and error semantics; integrate third-party APIs when needed
Develop backend services in .NET (.NET Framework, .NET Core)
Work with databases (MSSQL, Firebird), including query optimization, data merges, indexes, and pragmatic use of ORMs
Contribute to mobile development (.NET Maui, conversion of Xamarin Forms)
Level-up DevOps practices: contribute to CI/CD (GitHub Actions), environment configs/secrets, basic IaC where appropriate, and zero-downtime deploys
Instrument and observe applications (logs/metrics/traces)
Champion security basics (OAuth/OIDC/JWT, session management, update legacy authentication solutions
Raise the bar on code quality via thoughtful PR reviews, reusable abstractions, and incremental refactors
Collaborate tightly with Product and Design to shape scope, break work into milestones, and deliver predictable, incremental value
Qualification
Required
Bachelor's degree or equivalent practical experience
5+ years professional experience as a Full-Stack or Front-End-heavy Developer
Proven track record shipping production features
Comfortable with SQL and at least one relational DB; able to reason about data models and migrations
Experience integrating and securing REST APIs
Solid grasp of Git/GitHub workflows, testing, and CI/CD
Clear, proactive communication; able to own projects with minimal oversight while collaborating in a team
Web Development / Full stack / .NET (Senior Level)
Webpay site is in .NET 4.7.2 and MSSQL
APIs development and management
Web forms development and management
Preferred
Experience with VB6 and .Net - Desktop Development
Familiarity with Azure Infrastructure
Familiarity with InstallShield
Company
Fullsteam
Backed by Aquiline Capital Partners and ADIA, Fullsteam is a dynamic and growing team of 1,700 employees committed to driving innovation and delivering best-in-class software and payment solutions that empower small and medium-sized businesses across numerous industries.
H1B Sponsorship
Fullsteam has a track record of offering H1B sponsorships. Please note that this does not
guarantee sponsorship for this specific role. Below presents additional info for your
reference. (Data Powered by US Department of Labor)
Distribution of Different Job Fields Receiving Sponsorship
Represents job field similar to this job
Trends of Total Sponsorships
2021 (1)
2020 (1)
Funding
Current Stage
Late StageTotal Funding
unknownKey Investors
Aquiline Capital PartnersSixth Street
2023-05-25Private Equity
2021-12-02Private Equity
Leadership Team
Recent News
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