Senior Software Engineer (API & Auth Platform)

Betterment; New York (NY); On-site; USD 150,000 - 190,000; Full time

Benefits offered by this job

Equity for everyone

401(k) match + student loan matching

One Medical membership

Flexible time off

Parental leave

Sabbatical after year six

In‑person culture

Coaching and development

Employee support

Job summary

Betterment is seeking a Senior Software Engineer to own and evolve the API & Auth Platform that powers our customer‑facing apps and internal tools. You’ll steward GraphQL frameworks, authentication, and developer tooling in a regulated financial services context.

You will collaborate with product, operations, and compliance partners, mentor engineers, and help shape safe AI‑enabled API development while maintaining high standards for reliability and security.

Qualifications

• Experience building and operating a GraphQL API platform.
• Strong authentication/authorization experience with modern patterns.
• Fullstack capability including GraphQL and server-side languages.
• Comfort with observability, testing, and safe rollout in production.
• Ability to mentor junior engineers and collaborate across teams.

Responsibilities

• Build and advance the GraphQL API frameworks powering Betterment’s apps.
• Contribute to authentication and authorization systems and internal tooling.
• Collaborate with product, operations, support, and compliance teams.
• Shape direction of shared API platforms and developer tooling.
• Support AI tooling adoption and safe access to APIs.

Skills

GraphQL

Authentication/Authorization

Fullstack development

Server-side languages

Observability

Testing

Incident response

Mentoring

Tools

GraphQL frameworks

OAuth 2.0

OIDC

Passkeys

Job description

• The API & Auth Platform team enables product teams across Betterment to build and operate APIs quickly, enjoyably, and securely. As Sr Software Engineer, you will work with a team of senior/staff engineers stewarding our shared GraphQL API frameworks, authentication and access control systems, and internal tooling platform
• You will help build core pieces of the GraphQL API frameworks powering our customer-facing web and mobile applications, working closely with engineering leadership. You will also collaborate with operations, customer support, and compliance partners to ensure our internal APIs let teams operate Betterment systems with the rigor our customers and regulators expect
• As AI tooling reshapes how we build and operate our systems, you will have significant influence over how Betterment’s APIs support AI agents and tooling safely in a regulated financial services environment
• Work with a team of senior/staff engineers building the API, authentication, and internal tooling foundation that every Betterment team relies on
• Help deliver the GraphQL API frameworks powering our customer-facing and internal apps, including agentic tooling for AI-native API development workflows
• Contribute to Betterment’s authentication and authorization systems, keeping them current with industry best practices
• Build platform capabilities like secure, first‑party MCP access to Betterment APIs — and the reliability, security, and developer experience work that makes them trustworthy
• Embed with the product teams who build on your platform every day. Develop broad Betterment domain expertise in the process
• Help make the standards that keep shared systems healthy visible and easy to meet, and help teams understand the “why” behind them
• Participate in efficient, blameless incident response across your team and the teams building on the API platform. Invest in observability that serves both developers and internal tool users
• Mentor junior engineers, sharing your experience to expand their impact and accelerate their growth

Benefits

• Compensation & Ownership: Competitive, benchmarked salary. Equity for everyone, including new hire, performance, and refresher grants.
• Retirement: 401(k) match from day one, including Student loan matching. Zero management fees.
• Health & Wellbeing: Comprehensive medical, dental, and vision coverage. One Medical membership. Fertility and LGBTQIA+ transition support.
• Time Away: Flexible time off. Paid parental leave for all parents. Four‑week sabbatical in year six.
• In‑Office Culture & Flexibility: An in‑person, collaborative culture, with no required office days during the summer and winter holidays.
• Growth & Development: Free Coaching for everyone and continuous development.
• Community & Care: Chef lunches, guest speakers, company gatherings, heritage celebrations, and seven Employee Resource Groups.
• Employee Support: Dedicated benefits advocate and EAP access.

A contributor capable of working in sensitive auth systems, working alongside senior and staff IC colleagues to shaping their technical directionExperience with modern authentication/authorization patterns (OAuth 2.0, OIDC, passkeys), with an appreciation for the importance of adoption, long‑term support, and security testingExperience building on or contributing to a shared API platform — ideally GraphQL — with an appreciation for the frameworks, conventions, and developer tooling that let product teams introduce new capabilities, support existing usage, and gracefully retire legacy functionalityExperience collaborating across discipline and team boundariesExperience operating systems in production that other engineering teams depend on, with an eye for observability, testing, and safe rolloutFullstack development experience including GraphQL and one or more server‑side languages (Ruby, Java, TypeScript, C#, Python, etc.)Comfort with the evolving AI landscape — using AI tooling in your own workflow and thinking clearly about how AI agents should access APIs safelyAn open‑minded approach when navigating the tension between moving fast, customer quality, and regulatory requirements