Principal Full Stack Engineer

Liberty Mutual Insurance; Portsmouth (NH); Hybrid; USD 140,000 - 170,000; Full time

Job summary

Liberty Mutual Insurance in Portsmouth, NH is seeking a Principal Full Stack Engineer to join a hybrid team delivering cloud-native, enterprise-level applications. You will design, develop, and optimize multi-platform solutions, mentor teammates, and collaborate with cross-functional groups to drive engineering excellence.

Role emphasizes hands-on coding with Java Spring Boot, Node.js, API design, and modern architectures while fostering a culture of continuous improvement and reliable delivery.

Qualifications

• Bachelor's degree in a technical discipline or equivalent experience.
• 8+ years of full stack development experience with Java and frontend stacks.
• Experience with cloud native architecture and modern API design.

Responsibilities

• Develop modern cloud-based enterprise applications.
• Lead technical design, development, and integration of solutions.
• Coach the broader team on best practices and modern design.
• Define technology standards, guidelines, and coding practices.
• Architect large-scale web applications with cross-functional teams.
• Hands-on modernization, site reliability, and API layers (Java Spring Boot, Node.js).
• Collaborate with vendors and cross-functional teams to deliver solutions.
• Address production issues and drive incident resolution.

Skills

Full stack development

Mentoring & leadership

Agile methodology

Problem solving

Communication

Education

Bachelor's Degree in computer science or software development or equivalent

Tools

React

MobX

Semantic UI

MySQL

Oracle

Git

Docker

AWS Lex/Lambda

Amazon Connect

NodeJS

TypeScript/JavaScript

DataDog

Java (8+/11/17)

Spring/Spring Boot

REST APIs

OpenAPI

Hibernate/JPA

CI/CD

GitHub Actions

Job description

Description

We deliver our customers peace of mind every day by helping them protect what they value most. Our passion for placing the customer at the center of everything we do is driving a transformational shift at Liberty Mutual. Operating as a tech startup within a Fortune 100 company, we are leading a digital disruption that will redefine how people experience insurance.

We deliver our customers peace of mind every day by helping them protect what they value most. Our passion for placing the customer at the center of everything we do is driving a transformational shift at Liberty Mutual. Operating as a tech startup within a Fortune 100 company, we are leading a digital disruption that will redefine how people experience insurance.

At Liberty, you'll thrive in a hybrid setting that fosters in-person collaboration, innovation and growth. This approach optimizes both remote and in-person interactions, enabling you to connect and ideate with your team and deepen valuable relationships across the company, while still enjoying the flexibility of remote work for focused tasks and projects.

This role has a hybrid work schedule (2 days onsite) and we are considering candidates based in Portsmouth, NH and Boston, MA.

You must be authorized to work in the United States without employer sponsorship now or in the future. We will not sponsor employment visas. Candidates who will require future sponsorship, including candidates on CPT/OPT/STEMOPT who will require future sponsorship, are not eligible to apply.

Job Introduction

The Global Finance Technology organization is looking to hire a Principal Full Stack Engineer. The candidate will be part of a talented agile team and will have the opportunity to work on cutting‑edge projects. We are seeking a driven and creative individual who is able to think strategically and collaborate effectively with cross‑functional teams.

Candidate will be responsible for technical design and development of cross‑functional, multi‑platform applications that solve complex business problems. The role will be a highly visible hands‑on technology driver supporting platform product development by creating innovative solutions, as well as driving solutions that modernize, stabilize, and support the growth of our portfolio. You will interact with business and tech teams and focus on solution design, development, debugging and performance tuning.

About The Job

• Develop modern enterprise-level applications in the cloud.
• Lead & mentor the technical design, development, and integration of solutions using existing and emerging technology platforms.
• Influence and coach the broader technical team to help push best practices and understanding of modern design and development practices.
• Define technology standards, guidelines, and coding practices for the platform.
• Create architectures for large-scale web-based applications and technology solutions, by collaborating with other architects/technical leads.
• Become a subject matter expert and gain a deep understanding of the Platform Application and Infrastructure framework.
• Work closely with cross-functional teams and applicable vendors.
• Hands‑on development with a focus on application modernization, site reliability, containerization, and building appropriate API layers in Java Spring Boot, Node.js, and other distributed technologies.
• Participate in critical production issues, driving teams towards incident & problem ticket closure.
• Participate in fit/gap analysis of requirements, help manage user expectations on feature deliverables, provide tactical and strategic options to address issues and technical debt, and develop code to modern standards.

Qualifications

• Bachelor's Degree in technical discipline, preferably computer science or software development or equivalent experience.
• Minimum 8 + years of Full Stack Development experience primarily using the following technologies in addition to Java: React, MobX, Semantic UI, MySQL, Oracle, Git, and Docker.
• Experience with AWS services for IVR, e.g., Lex and Lambda, plus Amazon Connect.
• Experience with API development using NodeJS and TypeScript/JavaScript
• Experience with application observability tools, e.g., DataDog.
• Extensive professional experience developing applications using Java (Java 8+ / 11 / 17).
• Strong proficiency in object-oriented design, data structures, and design patterns.
• Hands‑on experience with Spring / Spring Boot, including RESTful services and dependency injection.
• Experience building and consuming APIs (REST, JSON, OpenAPI).
• Solid understanding of multithreaded programming, concurrency, and performance tuning.
• Experience with relational databases (Oracle, PostgreSQL, MySQL) and ORM frameworks such as Hibernate/JPA.
• Familiarity with CI/CD pipelines, automated testing, and version control (Git) and GitHub Actions.
• Strong troubleshooting skills with the ability to debug and resolve complex issues in production systems.
• A design thinking, test-driven development, and shift-left mindset.
• Ability to mentor others and raise a team's technical capabilities.
• Hands‑on involvement with layered systems architectures, designs and shared software concepts.
• Experience working in an agile environment.
• Excellent negotiation, facilitation and consensus‑building capabilities.
• Strong leadership, coaching and mentoring skills.
• Proven ability to speak to varying levels of the organization and successfully collaborate across the organization.
• Ability to work collaboratively with Agile methodologies (Scrum, Kanban) and cross‑functional teams (Product Owners, Software Engineers, Test Engineers) to drive technology decisions and support engineering excellence.
• Openness and adaptability to respond to fast-moving circumstances.
• Excellent oral and written communication skills. Aptitude for working in teams.

About Us

Pay Philosophy: The typical starting salary range for this role is determined by a number of factors including skills, experience, education, certifications and location. The full salary range for this role reflects the competitive labor market value for all employees in these positions across the national market and provides an opportunity to progress as employees grow and develop within the role. Some roles at Liberty Mutual have a corresponding compensation plan which may include commission and/or bonus earnings at rates that vary based on multiple factors set forth in the compensation plan for the role.

At Liberty Mutual, our goal is to create a workplace where everyone feels valued, supported, and can thrive. We build an environment that welcomes a wide range of perspectives and experiences, with inclusion embedded in every aspect of our culture and reflected in everyday interactions. This comes to life through comprehensive benefits, workplace flexibility, professional development opportunities, and a host of opportunities provided through our Employee Resource Groups. Each employee plays a role in creating our inclusive culture, which supports every individual to do their best work. Together, we cultivate a community where everyone can make a meaningful impact for our business, our customers, and the communities we serve.

We value your hard work, integrity and commitment to make things better, and we put people first by offering you benefits that support your life and well-being. To learn more about our benefit offerings please visit: https://LMI.co/Benefits

Liberty Mutual is an equal opportunity employer. We will not tolerate discrimination on the basis of race, color, national origin, sex, sexual orientation, gender identity, religion, age, disability, veteran's status, pregnancy, genetic information or on any basis prohibited by federal, state or local law.

Fair Chance Notices

• California
• Los Angeles Incorporated
• Los Angeles Unincorporated
• Philadelphia
• San Francisco