The Opportunity

We’re looking for a Senior Growth Full-Stack Engineer to join our Activation team at Seamless.AI. This role sits at the intersection of engineering, product, and growth, helping us design, build, and run experiments that accelerate user onboarding, engagement, and activation. You’ll partner closely with growth product managers, designers, and analysts to rapidly ship and iterate on experiments that improve how new users discover value in Seamless.AI.

Responsibilities

Collaborate with growth, product, and data teams to design and implement A/B tests and growth experiments focused on user activation.
Build, deploy, and maintain full-stack features and experiment infrastructure (frontend + backend).
Implement and manage feature flagging systems to enable rapid testing and controlled rollouts.
Work with GrowthBook (or similar experimentation platforms) to set up, track, and analyze experiments.
Instrument and track user behavior in Amplitude and other analytics platforms to generate insights.
Write clean, scalable, and maintainable code across the React frontend and Node.js backend.
Monitor and evaluate experiment outcomes, providing actionable insights and recommendations.
Balance speed of experimentation with engineering best practices, ensuring quality while moving quickly.
The #1 goal of this position is to help Seamless.AI increase user activation, feature adoption, and time-to-value. These efforts will maximize customer retention & satisfaction.

Skillset

5+ years of experience as a full-stack engineer (startup or growth-focused environment preferred) with SaaS product.
Strong proficiency in modern JavaScript/TypeScript (React.js, Node.js)
Proficiency with modern database technologies (PostgreSQL, Vector DBs, OpenSearch, DynamoDB)
Proficiency with Cloud architecture and scalability best practices, in particular AWS (Lambda, serverless, cloud-native services).
Hands-on experience with A/B testing platforms (GrowthBook, Optimizely, LaunchDarkly, etc.).
Familiarity with feature flag systems and controlled experiment rollout strategies.
Experience with product analytics tools (Amplitude, Segment, Tableau).
Ability to translate growth hypotheses into technical experiments quickly and iteratively.
Strong data-driven mindset with the ability to evaluate experiment outcomes statistically.
Comfortable working in fast-moving, cross-functional growth teams.

Preferred:

Background in PLG, growth engineering, activation, or onboarding-focused roles.
Experience with event-driven architecture and scalable systems.
Familiarity with in-app education & onboarding tooling (e.g., Userflow).
Familiarity with Pinecone and LLMs.
Experience building SaaS applications in the B2B or productivity space.

Education & Requirements

Bachelor’s degree in Computer Science, Engineering, or a related field (or equivalent practical experience).
Proven experience delivering full-stack features and experiment infrastructure in a fast-paced environment.
Demonstrated ability to collaborate across engineering, product, and growth teams.
Strong problem-solving and analytical skills with a data-first approach.

Check out what our employees think about working at Seamless: CLICK HERE

Since 2015, Seamless.AI has helped sales teams maximize revenue with the world’s first real-time B2B search engine. As one of Ohio’s fastest-growing companies, we’ve earned top industry accolades, including G2’s 2025 Best Software Products (#1 Highest Satisfaction Product), Purpose Jobs’ 2024 Best Places to Work, and LinkedIn’s Top 50 Tech Startups (2020, 2022, 2023). We are committed to a diverse, inclusive workplace and do not discriminate based on race, religion, gender, sexual orientation, age, or other protected statuses. Visa sponsorship is not available; applicants must be authorized to work in the U.S.