Senior Frontend Software Engineer

Sardine; United States; Remote; USD 140,000 - 190,000; Full time

Benefits offered by this job

MacBook Pro delivered to your door

Remote-first culture

Generous equity

Unlimited PTO and mandatory vacation

401k with 4% match

Full health/dental/vision coverage

Job summary

Sardine in the United States is seeking a senior frontend software engineer to own the design and delivery of user-facing experiences in our AI products. You will build polished, production-grade interfaces in React and TypeScript, while dipping into Go for backend services when needed.

This high-autonomy role requires leadership, mentorship, and a focus on performance, accessibility, and best practices for AI-assisted development across the team.

Qualifications

• 7+ years as a software engineer with frontline frontend focus.
• Proven track record shipping production-grade frontend at scale.
• Strong React/TypeScript craftsmanship and UX sensibility.
• Experience mentoring engineers and setting technical standards.
• Fluency with AI-assisted development tools and workflows.

Responsibilities

• Own design and delivery of user-facing experiences in our AI products.
• Build polished, performant interfaces in React and TypeScript.
• Collaborate with stakeholders to architect new experiences from inception to delivery.
• Mentor engineers, review code, and raise engineering standards.
• Use AI tooling (e.g., Claude) to accelerate development and establish best practices.

Skills

Frontend development

Leadership

English fluency

AI tools fluency

Customer-centric mindset

Mentoring engineers

Go familiarity

Fintech domain experience

Tools

TypeScript

React

Node.js

Golang

Bigtable

PostgreSQL

BigQuery

Python

Java

Terraform

Job description

• As a frontend-focused Senior Software Engineer, you will own the design and delivery of the user-facing experiences at the heart of our AI products


• Your primary focus is building polished, performant, production-grade interfaces in React and TypeScript


• You’ll also work in Go on the backend services and APIs that power those experiences, but that’s a secondary part of the role


• This is a high-autonomy, high-leadership position: you’ll develop new features at scale, set the standard for how we build on the frontend, mentor the engineers around you, and use AI/agentic tooling (like Claude) to ship far faster than a traditional team would


• The ideal candidate pairs exceptional frontend craft with the judgment to lead and the discipline to be relentlessly efficient with modern, AI-assisted workflows


• Design, build, and own user-facing features in React and TypeScript — polished, accessible, performant, and production-ready


• Set the technical direction and quality bar for our frontend, and lift the people around you through mentorship and code review


• Use AI and agentic development tools (such as Claude) fluently and effectively to move quickly, and help establish best practices for AI-assisted development across the team


• Dip into Go to build and extend the backend services and APIs behind your features when needed


• Collaborate closely with business stakeholders to architect and implement new experiences from inception to delivery


• Contribute to product and technical roadmaps, and to the broader direction of the engineering team


• Craft and maintain user-facing technical documentation that drives understanding and adoption of our products


• Play a pivotal role in shaping our engineering culture and ensuring high standards across the organization


• Technologies we use:


• TypeScript (React + Node)


• Golang


• Bigtable


• Postgres / PostgreSQL


• BigQuery


• Python


• Java


• Terraform

Benefits

• MacBook Pro delivered to your door


• Annual fitness allowance


• Work from anywhere: Remote-first Culture


• Generous equity compensation


• Unlimited paid time off and minimum 2 weeks/year of mandatory vacation


• Monthly meal stipend


• Unlimited access to an expert financial advisory


• One-time stipend to set up a home office — desk, monitors, etc


• 4% matching in 401k


• 100% of health insurance, dental, and vision coverage for employees and 50% for dependents


• Company-wide offsites, the last one was at Miami

• Comfort with ambiguity and the ability to prioritize autonomously against business needs


• A track record of shipping high-quality, production-grade frontend at scale


• Demonstrated fluency with AI and agentic coding tools (e.g., Claude), and a track record of using them to ship efficiently and raise your own throughput


• Leadership experience: setting technical standards, mentoring engineers, and driving key technical decisions


• Working proficiency in Go (or the ability to become productive in it quickly) for backend services — secondary to your frontend work


• 7+ years of proven experience as a software engineer, with deep specialization in frontend development


• Proficient in English — from casual chats to formal reports


• Relevant industry experience in fintech, fraud, compliance, risk, or regulated systems is preferred


• Customer-centric approach with strong empathy toward users


• Expert-level React and TypeScript, with a strong eye for UX, performance, and accessibility


• Exposure to data tooling or pipelines is a nice-to-have, but not required