Sr Software Engineer II

Senior Software Engineer II - Remote (USA)

Pax8 is seeking a Senior Software Engineer II to help build the next generation of Pax8’s financial infrastructure. This is a greenfield, mission-critical platform where correctness, auditability, and scalability are non-negotiable.

Why this role stands out

This role is part of a newly formed FinTech Product & Engineering organization, responsible for building Pax8’s core financial engine from the ground up. This is true 0→1 work, not a refactor. You’ll help design and deliver systems that safely move, track, and reconcile money across the Pax8 ecosystem, working in an AI-forward environment with modern tooling that accelerates real delivery.

Life at Pax8

Pax8 is where ambitious technology meets human-centered culture. We’re fast-growing, creatively offbeat, and serious about building software that matters. You’ll join a team that values curiosity, ownership, and craftsmanship, where internal growth and fairness are taken seriously alongside high performance.

Learn more about our culture and mission on the Pax8 Careers page and explore how we’re evolving our platform on the Pax8 Blog.

What You’ll Do

• Build net-new financial systems: design and deliver Pax8’s core financial infrastructure with a focus on auditability, scalability, performance, and bullet-proof money handling.
• Own complex financial domains: model transactions, events, and ledgers with clear domain boundaries and strong guarantees of correctness.
• Design event-driven architectures using Kafka and asynchronous patterns to support reliable, traceable financial flows.
• Apply Domain-Driven Design: shape clean domains, event models, and system boundaries that will scale with the business.
• Collaborate deeply with product, engineering, and adjacent teams to turn complex financial requirements into working systems.
• Lead through example: contribute to design and code reviews, mentor peers, and raise the engineering bar without formal people management.
• Support production systems: participate in on-call rotations for critical financial workflows where accuracy and calm execution matter most.
• Deliver faster with AI: use coding agents and generative AI to accelerate implementation, testing, and documentation while maintaining full ownership of quality.

The impact you’ll make

You’ll help create the financial backbone of Pax8 — systems where mistakes are unacceptable, trust is paramount, and scale is built in from day one. Your work will directly support compliance, partner confidence, and Pax8’s ability to grow responsibly.

What You’ll Bring

• Proven experience building financial or money-handling systems (e.g., billing, payments, ledgers, transaction platforms) where correctness and auditability are critical.
• Strong understanding of financial integrity, compliance expectations, and failure modes, even outside traditional banking environments.
• Substantial backend engineering expertise with Kotlin and Spring Boot, building production-grade services.
• Demonstrated experience with event-driven architectures and tools such as Kafka, especially for financial workflows.
• Comfort designing systems using Domain-Driven Design, clean domain boundaries, and explicit event models.
• Ability to operate confidently in environments where errors have real consequences and quality cannot be compromised.
• A practical, hands-on approach to AI-enabled development using coding agents, spec-driven workflows, and AI-assisted testing as part of daily delivery.
• The presence and maturity to operate at Senior Software Engineer II level immediately, contributing leadership while supporting internal mobility and team growth.

Trust And How We Hire

At Pax8, we care deeply about building genuine, trust-based relationships — starting with how we hire. To protect our business, our teams, and our customers, we use a range of measures throughout the recruitment process to help confirm authenticity and prevent fraud. These safeguards are designed to be fair, respectful, and proportionate, and may evolve as risks change. By applying, you acknowledge that we take steps to verify identity and representation during hiring. If you're applying as your authentic self, you have nothing to worry about — we're excited to meet you.

We also use thoughtfully applied AI-enabled tools to support our hiring process. These tools may assist with tasks such as reviewing or prioritizing applications, but hiring decisions are made by our people. More information is available in our Recruitment Privacy Notice. If you have questions about how we hire or would prefer not to have your application supported by these tools, you can opt out at any part of our process.

Inclusivity

We encourage you to apply even if you don't meet 100% of the criteria. We're committed to diverse perspectives, inclusive hiring, and sharing your transferable skills. To fulfill this role, you must hold valid right to work in USA.

Salary & Benefits

Target base salary: $170,000 – $185,000, or more depending on experience.

At Pax8, we believe that your total rewards should include a benefits package that shows how much we value our greatest assets. All FTE Pax8 People Enjoy the Following Benefits:

• Non-Commissioned Bonus Plans or Variable Commission
• 401(k) plan with employer match
• Medical, Dental & Vision Insurance
• Employee Assistance Program
• Employer Paid Short & Long Term Disability, Life and AD&D Insurance
• Flexible, Open Vacation
• Paid Sick Time Off
• Extended Leave for Life events
• RTD Eco Pass (For local Colorado Employees)
• Career Development Programs
• Stock Option Eligibility
• Employee-led Resource Groups

Expected Closing Date: 6/19/2026

Growth at Pax8

There's extensive room for a talented individual to grow at pace, whether that's advancing quickly in this role or exploring one of the many opportunities across our global organization. You'll have access to our internal development hub designed to accelerate your skills and stretch your potential. Alongside specialist Learning & Development trainers, you'll also tap into AI-powered tools, "born in the cloud" mentors, and cross-continent collaboration that broaden your perspective and sharpen your expertise. We'll give you the space, trust, and the right projects to help you thrive — and full visibility of what it takes to reach your next level.

About Pax8

Our mission is to build the managed intelligence marketplace and empower small businesses to do more with smarter technology. We are a fast-growing, dynamic, and high-energy organization with a start-up feel, allowing you to make a meaningful impact on the business. Culture is also important to us, and at Pax8, it's business, and it IS personal. We are passionate, creative, and unconventional. We work hard, keep it fun, and expect the best! We Elev8 each other. We Advoc8 for our partners. We Innov8 continuously. We Celebr8 life.

Background checks

As part of our hiring process, we are required to undertake pre-employment checks on all candidates who are successful in their application with Pax8. As part of these checks, Pax8 will request ID verification, reference requests, and qualification checks. Additional checks may be completed for certain countries, such as criminal and financial. All checks are completed by our third-party provider, First Advantage. Once checks have been completed, all candidates will receive a copy for their records.

Equal opportunities

Pax8 is an equal opportunities employer and welcomes individuals who are in possession of the appropriate requirements to work within the country you have applied for. Offered individuals will be asked to undertake identity, security compliance, and reference checks. Your privacy is important to us. Your data will be held in accordance with local best practices and processed only in accordance with our recruiting processes. Privacy notice: Pax8 Job Applicant Privacy Notice.

At Pax8, we care deeply about building genuine, trust-based relationships — starting with how we hire. To protect our business, our teams, and our customers, we use a range of measures throughout the recruitment process to help confirm authenticity and prevent fraud. These safeguards are designed to be fair, respectful, and proportionate, and may evolve as risks change. By applying, you acknowledge that we take steps to verify identity and representation during hiring. If you’re applying as your authentic self, you have nothing to worry about — we’re excited to meet you.

Perks

Why Join Pax8?

Because here, success isn't just about numbers—it’s about impact. It’s about being part of a team that thinks bigger, empowers each other, and never loses sight of why we do what we do: to make the cloud easier, more accessible, and more meaningful.

At Pax8, we believe that your total rewards should include a benefits package that shows how much we value our greatest assets. All FTE Pax8 People Enjoy the Following Benefits:

• Non-Commissioned Bonus Plans or Variable Commission
• 401(k) plan with employer match
• Medical, Dental & Vision Insurance
• Employee Assistance Program
• Employer Paid Short & Long Term Disability, Life and AD&D Insurance
• Flexible, Open Vacation
• Paid Sick Time Off
• Extended Leave for Life events
• RTD Eco Pass (For local Colorado Employees)
• Career Development Programs
• Stock Option Eligibility
• Employee-led Resource Groups

Please take a moment to review our Proprietary Rights and Non-Competition Agreement — this document outlines important information about your rights and responsibilities if you join our team.

Pax8 is an EEOC Employer.

Equal Opportunities

Pax8 is an equal opportunities employer and welcomes individuals who are in possession of the appropriate requirements to work within the country the role is based in. Offered individuals will be asked to undertake identity, security compliance, and reference checks. Your privacy is important to us. Your data will be held in accordance with Data Privacy best practices and processed only in accordance with our recruiting processes. Job Applicant Privacy Notice.

Key skills/competency

• Senior Software Engineer II
• Financial Infrastructure
• Greenfield Platform Development
• Auditability and Scalability
• Domain-Driven Design
• Event-Driven Architecture
• Kafka
• Kotlin
• Spring Boot
• AI-enabled Development