Founding Staff Software Engineer • Python/FastAPI

ABOUT the company

The company is building the AI recruiting operating system, one unified platform for your entire talent organization, from first touch to hired. Arbi eliminates fragmented workflows, integrates directly with your ATS, and orchestrates AI agents for sourcing, outreach, screening, and candidate intelligence end-to-end. By combining reasoning-optimized models with deep workflow automation, Arbi helps talent teams win more top candidates with dramatically less friction.

We’re backed by top operators and investors, and we’re growing fast. Our momentum is further fueled by blue-chip partners and programs, including the NVIDIA Inception Program, the HPE Unleash AI Program, and our active DoD SBIR Phase II award and contract.

We’re now hiring a Founding Staff Software Engineer to help accelerate features on Arbi to help us dominate one of the largest and fastest-expanding categories in modern software.

This is not a maintenance role. This is a hands-on, high-ownership opportunity for someone who has operated at a staff engineer, architect, or founding/lead engineer level and knows how to build production-grade systems that scale. You will work on the backbone of our platform: APIs, orchestration systems, data workflows, search infrastructure, background jobs, cloud deployment, and backend systems that power AI-enabled products for real customers.

THE ROLE

We’re hiring a Founding Staff Software Engineer to help us scale and evolve our core systems. You'll work closely with AI engineers, frontend devs, and product leads to build the APIs, services, and infrastructure powering our agentic workflows.

This is a hands-on role for someone who knows how to build enterprise-grade backends using modern Python/FastAPI stacks. You’ll lead major technical efforts, make architecture decisions that scale, and help us stay fast, reliable, and resilient as our user base grows.

WHAT YOU'LL DO & OWN

• Design, build, and maintain robust backend systems that power the company AI’s core platform

• Develop and scale REST APIs using Python and FastAPI

• Build production-ready systems using PostgreSQL, Redis, OpenSearch, Celery, and Temporal

• Architect and optimize systems that handle large-scale datasets and high-throughput backend workflows

• Build, deploy, and maintain backend services on AWS

• Own containerized deployments, CI/CD pipelines, and backend infrastructure reliability

• Support integrations, data pipelines, workflow automation, and asynchronous processing systems

• Help define backend architecture, engineering standards, observability, and performance practices

• Work closely with product, AI, and frontend teams to deliver features that power B2B and B2C SaaS experiences

• Mentor engineers and raise the bar on engineering quality, speed, and execution

• Operate like an owner in a startup environment, balancing speed with sound engineering judgment

• Contribute to AI-enabled engineering workflows and modern developer tooling, including tools such as Cursor and/or Claude Code

WHO YOU ARE

• Strong backend engineering experience with Python

• Deep hands-on experience with FastAPI

• Strong production experience with PostgreSQL and Redis

• Experience using OpenSearch

• Hands-on experience with Celery and Temporal

• Proven experience building robust REST APIs

• Experience working with large-scale datasets

• Experience deploying and managing backend systems on AWS

• Hands-on experience with AWS services, containers, and deployment pipelines

• Experience building, deploying, and maintaining production systems for B2B and/or B2C SaaS

• Experience supporting integrations, data pipelines, and/or workflow automation

• Prior experience operating as a Staff Engineer, Lead Engineer, Founding Engineer, or Architect

• Experience working in startup-style environments with high ownership and mentoring responsibility

• Strong systems thinking, sound backend architecture judgment, and the ability to move from idea to production

• Ability and willingness to relocate to Northern VA/DC

BONUS POINTS

• Have built backend platforms that became the foundation for a growing product

• Know how to balance speed, scale, reliability, and developer experience

• Have strong instincts around designing for maintainability, observability, and performanceEnjoy owning ambiguous problems and turning them into simple, durable systems

• Can mentor others while still being deeply hands-on

• Are excited by AI-enabled software development and modern engineering workflows

• Want to help shape both the codebase and the culture of an early-stage company

• Experience building AI-enabled products or backend systems that support AI workflows

• Experience with search-heavy, data-intensive, or workflow-centric products

• Experience in recruiting tech, HR tech, SaaS platforms, or decision-support systems

• Experience designing backend systems for multi-tenant SaaS environments

• Experience improving developer productivity using Cursor, Claude Code, or similar AI coding tools

• Experience with event-driven systems, job orchestration, and resilient distributed workflows

• Experience helping scale an early-stage engineering team

• Experience working directly with product and leadership in a founding-stage company

WHAT’S IN IT FOR YOU

• Join a tight-knit engineering team shipping fast and building with ambition

• Work on products used by real-world recruiters, analysts, and decision-makers

• Be part of a mission-driven company redefining how humans and AI collaborate

• Competitive salary, meaningful early-stage equity, and flexible work arrangements

• Zero bureaucracy, high trust, and a strong culture of ownership and technical excellence

• The opportunity to join as a founding backend engineering leader and help define the technical core of the company AI

• Significant ownership over architecture, tooling, and backend platform decisions

• Direct exposure to company leadership and the ability to influence product direction

• A chance to build systems that matter from day one rather than inheriting legacy architecture

• The pace, autonomy, and impact of a startup, with meaningful room for growth

• The ability to help shape how AI-native products are built and delivered in production

• A seat at the table as we scale our product, team, and engineering culture

• Base Salary: $100K–$200K

• Performance bonus: Quarterly bonuses tied to clear feature shipping targets

• Equity: Meaningful early-stage equity (~0.1-0.75%) with a clear range shared during the process

• Benefits: Medical, dental, vision, 14-days of PTO accrued annually

• Learning: At least $2,000 per year for courses, events, books, and growth communities

• Tools and setup: New macbook pro, monitor, and a monthly tools budget to run the stack you want

• Flexibility: Flexible hours, in-person.

• Growth path: Clear, fast-track path to an Engineering Lead as we scale the team

This role is ideally suited for candidates who are open to working closely with the team and are willing to relocate to Northern Virginia / Washington DC region.

EQUAL OPPORTUNITY

The company is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees. We welcome applicants from all backgrounds, identities, and walks of life — including but not limited to race, gender, age, religion, sexual orientation, and disability status.