Sr Fullstack Developer Jobs in Maine (NOW HIRING)

About FullStack
FullStack is one of the fastest-growing software consultancy companies in the Americas. We deliver transformational digital solutions to top global companies and Silicon Valley startups. As an employee-first company, we focus on hiring the most talented software designers and developers by creating a positive, respectful, and supportive work environment where they can achieve their greatest potential.
We're most proud of:

• Offering life-changing career opportunities to talented software professionals across the Americas.
• Building highly-skilled software development teams for hundreds of the world's greatest companies.
• Having delivered hundreds of successful custom software solutions, which have positively impacted the lives and careers of millions of users.
• Our 4.2-star rating on GlassDoor.
• Our client Net Promoter Score of 68, twice the industry average.

The Position
We're looking to hire a Senior React + Node Engineer (Financial background) to join our team. You'll work with our incredible clients in one of two ways:

• Team Augmentation: You will integrate directly into our client's team and work alongside their existing designers and engineers daily.
• Design & Build: You will work on a FullStack product team to build and deliver a product to our clients.

What We Are Looking For

• 5+ years of professional software engineering experience.
• Advanced English is required.
• Successful completion of a four-year college degree is required.
• Expertise in Node.js (specifically versions 18 through 22).
• Proficient in React, including hooks, state management (Redux/Redux Saga), and component architecture.
• Proven experience in designing and maintaining financial data reconciliation systems, with a focus on ledger accuracy, complex data aggregation, and the programmatic generation of audit-ready reports.
• Track record of designing and maintaining microservices and distributed systems.
• Extensive experience with PostgreSQL, including advanced SQL, schema design, and query optimization.
• Well-versed in REST API development using modern frameworks like Koa.js or Express.
• Deep experience in ORM tools such as Objection.js, Sequelize, or TypeORM.
• Hands-on experience with AWS services (S3, SQS, RDS, EC2).
• Solid background in containerization using Docker and Docker Compose.
• Demonstrated experience with CI/CD pipelines (CircleCI, GitHub Actions) and GitOps practices.
• Skilled at implementing authentication systems such as JWT, OAuth, or MSAL (Azure AD).
• Strong history of testing discipline using Jest, Mocha, or Supertest.
• Practical experience with APM tools like DataDog or New Relic and feature flag management (LaunchDarkly).
• Solid understanding of financial or accounting systems (ledgers, reconciliation, etc.) is a plus.
• Ability to work through new and difficult issues and contribute to libraries as needed.
• Ability to create and maintain continuous integration and delivery of applications.
• Forensic attention to detail.
• A positive mindset and a can-do attitude.
• Experience working on Agile/Scrum teams.
• Meaningful experience working on large, complex systems (50k+ lines of code).
• Ability to take extreme ownership over your work. Every day is a challenge to ensure you are performing to the expectations you and your team have agreed upon.
• Ability to identify with the goals of FullStack's clients, and dedicate yourself to delivering on the commitments you and your team make to them.
• Ability to consistently work 40 hours per week.

What We Offer

• Competitive Salary.
• Paid Time Off (vacation, sick leave. parental leave, and holidays)
• 100% remote work.
• The ability to work with leading startups and Fortune 500 companies.
• Health, dental, and vision insurance.
• 401(k) w/ 4% match.
• Ample opportunity for career advancement.
• Continuing education opportunities.

FullStack is proud to be an equal opportunity workplace. We are committed to equal employment opportunity regardless of race, color, ancestry, religion, sex, national origin, sexual orientation, age, citizenship, marital status, disability, gender identity, or Veteran status.
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