Senior Full Stack Engineer

Localize is seeking an energetic, growth-minded Senior Full Stack Engineer to join our US-based remote team.

As a Localize engineer, you will be responsible for implementing new functionality within Localize’s core product. On the frontend you will work on our React/Redux single-page application, and on the backend you will build RESTful APIs in Node/Express/MongoDB.

As a key member of our remote engineering team, you will lead the development of high-impact product initiatives. We are looking for a strong engineer who works well on a small team and is excited about the opportunity to have a direct impact on improving customer experience.

• Implement new features and functionality within Localize’s core product.
• Build frontend features within our React/Redux single-page application.
• Develop and maintain REST APIs with Node/Express/MongoDB that power the frontend application.
• Own end-to-end delivery for product initiatives: discovery, technical design, implementation, testing, rollout, and iteration.
• Translate ambiguous problem statements into clear execution plans, including trade-offs, sequencing, and measurable outcomes.
• Be actively involved in product and architecture decisions.
• Modernize and evolve an existing codebase: identify and prioritize tech debt, improve patterns and architecture, and deliver incremental upgrades without disrupting customer value.
• Maintain a high engineering bar: readable code, solid tests, meaningful code reviews, and pragmatic documentation.
• Collaborate with other remote engineers (including pairing where beneficial) and engage meaningfully in peer code reviews.
• Diagnose and resolve production bugs throughout the development cycle, including incident response and measurable reliability improvements.
• Collaborate closely with Product, Design, and Customer-facing teams to ship the right thing and learn quickly.
• Improve platform fundamentals (architecture, observability, security, CI/CD, and developer experience).
• Lead by example: drive alignment, coach others, and take accountability for outcomes.

Experience with these specific technologies is a plus, but not strictly required.

• Frontend: TypeScript/JavaScript, React, Redux, Less
• Backend: JavaScript/TypeScript, Node.js, Express, Mongoose
• Datastores: MongoDB (Mongoose.js ODM), Redis, S3
• Infrastructure: AWS (Elastic Beanstalk, EC2, ElastiCache, CloudFlare, CloudFront, Route 53, etc.)
• DevOps / Misc: Git/GitHub, Jira, CircleCI, Mocha
• Applied LLM engineering:
  • Hands-on experience integrating LLMs into production systems (OpenAI, Anthropic, Gemini, or similar)
  • Strong understanding of prompt engineering, context engineering, and token management
  • Experience designing or implementing RAG pipelines, embeddings, and vector search
  • Familiarity with emerging LLM infrastructure patterns and protocols (e.g., MCP, tool/function calling, agents)

• 6+ years of professional experience building, deploying, and maintaining production web applications.
• Experience building complex single-page applications.
• Strong frontend skills: modern TypeScript/JavaScript, React, state management patterns, accessibility, and performance.
• Strong backend skills: Node.js + TypeScript, API design (REST and/or GraphQL), service architecture, and data modeling.
• Experience writing, maintaining, and integrating REST APIs written in Node/Express.
• Experience working with MongoDB and an understanding of common patterns and data structures, including schema design, indexing, and query performance.
• Experience leading large development initiatives requiring collaboration and coordination with fellow engineers.
• Proven ability to lead autonomously: scoping ambiguous work, writing short design docs, making decisions, and driving execution.
• Enthusiastic about learning, working within, and architecting high-impact products.
• Strong verbal and written communication skills, including clear stakeholder alignment and high-quality technical documentation.

Nice to have

• Experience leading or heavily contributing to platform modernization efforts (framework upgrades, build system improvements, dependency hygiene, improved test/observability coverage).
• AWS stack awareness (IAM, networking basics, compute/storage primitives, logging/monitoring), plus containers and CI/CD automation.
• Security-minded engineering (authn/authz, OWASP basics, secrets management, least privilege).
• Strong understanding of software design principles and common patterns (modular architecture, domain boundaries, testing strategy) and experience improving developer experience.
• Experience with analytics instrumentation and using metrics to guide iteration.
• Prior experience mentoring engineers, leading a small team, or acting as tech lead on multi-quarter initiatives.
• Familiarity with localization/i18n or developer tooling products (helpful but not required).

About Localize:

The Localize platform is used by 700+ companies to automate the translation of their web and mobile applications and bring their products & services to new markets at record speed. We support organizations like The Bay Area Toll Authority in translating their payments website, Baptist Health in making their healthcare site multilingual, and the Massachusetts Department of Elementary and Secondary Education in offering their content in several languages. To see our product in action, click any of those links and use the website's language switcher to switch from English to another language.

Localize works by providing a code snippet (similar to the Google Analytics JavaScript snippet) that our customers add to their website/web app. The Localize snippet pulls in content from the page into the Localize dashboard where our customers log in to add translations and manage their content. Localize automatically deploys those translations to the customer's production site, reducing development costs and accelerating time to market.

We are a team of ~30 people working fully remote. We offer competitive pay, a full benefits package, and a culture with an emphasis on work + life balance.

To apply:

Along with your resume, send us a cover letter that showcases your personality and tells us why we should hire you. Previous experience working in a remote position is a must.

This position is only open to applicants who reside in and are eligible to work in the US.