Senior Fullstack Engineer

Stash • New York, NY

3d • $170,000 - $190,000 • Hybrid

About The Position

Stash is seeking a Senior Fullstack Engineer to lead B2B engineering efforts for StashWorks, an emerging distribution channel connecting employees of partner companies with Stash products and benefits. The role is part of a small, collaborative team building and scaling the platform from the ground up. The engineer will own work spanning partner onboarding, employee eligibility and enrollment, identity and authentication, third-party integrations, lifecycle communications, and operational tools for employer partners. The position emphasizes leveraging AI coding assistants to accelerate software design and implementation while delivering reliable, maintainable systems.

Requirements

• 4–7 years of professional experience building software.
• Hands-on experience using AI tools such as Cursor or ChatGPT as a core part of daily workflows to improve productivity and output quality, and commitment to continuing to develop AI expertise.
• Ability to thrive in ambiguous, early-stage environments.
• Ability to work across services and codebases.
• Ability to write pragmatic, maintainable Go.
• Experience designing APIs and integrating external systems.
• Understanding of production operations, observability, security, and reliability.
• Ability to work effectively with product, operations, marketing, and partner-facing teams.
• Ability to balance rapid delivery with building scalable systems.

Nice To Haves

• Experience building applications at scale.
• Familiarity with or interest in Consul, multi-region systems, or multi-cloud design.
• Familiarity with or interest in Stash’s other technologies, including Spinnaker, CI/CD pipelines, Nginx, TypeScript, React, Node.js, Postgres, SNS/SQS, and AWS.

Responsibilities

• Act as an “Agent Conductor” to architect, design, and rapidly implement services using AI coding assistants.
• Own end-to-end software delivery from inception through production.
• Instrument, test, profile, and review code.
• Continuously deploy software to cloud-based infrastructure.
• Scale software infrastructure for a quickly growing user base.
• Build and scale platform capabilities spanning partner onboarding, employee eligibility and enrollment, identity and authentication, third-party integrations, lifecycle communications, and operational tools for employer partners.

Benefits

• Comprehensive total rewards package, including salary, equity, and health care benefits.
• Complimentary Stash+ account subscription.
• Hybrid work environment in NYC with work-from-home flexibility.
• Flexible PTO.
• Work-from-home equipment stipends and home internet subsidy.
• Paid parental leave for birth-giving and non-birth-giving parents, with primary and secondary offerings.
• Enhanced health and wellness benefits through One Medical, Gympass, and Maven Health.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed