Software Engineer II - Forms

About the Role

Klaviyo is looking for a Full Stack Software Engineer II to join the Signup Forms team. On Signup Forms you’ll help rebuild and evolve one of Klaviyo’s core growth surfaces so brands can reliably capture high-intent profiles across web, SMS, and messaging channels.

The team is explicitly focused on improving reliability and developer experience while making leaps in both AI enablement and enterprise-level scale. This role is about delivering both the foundations and the pieces that unlock those higher-level platform capabilities.

As a Software Engineer II you’ll own non-trivial end-to-end pieces of the product: design and ship well-tested frontend and backend work, weigh trade-offs between reliability, performance, and developer velocity, and help make architectural decisions within the team’s roadmap. You’ll routinely tackle complex problems and deliver pragmatic, maintainable solutions that improve both customer outcomes and the team’s developer experience.

Within the organization, we focus on making experiences part of an extensible, channel-agnostic, enterprise-grade platform. That includes the web experiences, APIs, and backend orchestration that power validation, actions, and delivery alongside the analytics and data plumbing that connect form events to profiles and downstream messaging. You’ll partner closely with product, design, analytics, and other engineering teams to deliver best-in-class customer-facing experiences.

• A proven track record of building high-quality products and systems, with a focus on writing clean, maintainable code
• 3+ years of experience in a software engineering role
• Experience building end-to-end software solutions or deep experience with both front-end and back-end technologies
• Familiarity with code reviews and leading or participating in robust testing practices
• Experience working in agile, fast-paced environments
• Experience driving technical solutions in cross function teams within an organization
• Quick learners that can raise the team’s bar while

• Experience with React, Typescript and related technologies
• Experience with Python and related technologies
• Background in digital marketing or customer data software
• Exposure to machine learning concepts or applications
• Experience building cloud-native solutions, ideally on AWS

We use Covey as part of our hiring and/or promotional process. For jobs or candidates in NYC, certain features may qualify it as an AEDT. As part of the evaluation process we provide Covey with job requirements and candidate submitted applications. We began using Covey Scout for Inbound on April 3, 2025.

Please see the independent bias audit report covering our use of Covey here