Principal Engineer (AI Fluent)

Principal Engineer (AI Fluent) 

About Payoneer 

Founded in 2005, Payoneer is the global financial platform that removes friction from doing business across borders, with a mission to connect the world’s underserved businesses to a rising global economy. We’re a community with over 2,500 colleagues all over the world, working to serve customers, and partners in over 190 countries and territories. 

By taking the complexity out of the financial workflows–including everything from global payments and compliance to multi-currency and workforce management, to providing working capital and business intelligence–we give businesses the tools they need to work efficiently worldwide and grow with confidence.  

Role summary  

Ramat Hasharon, Herzliya. 

Hybrid  
Full-time  

We are looking for an engineer who can take ownership of a solution from understanding the business problem through production delivery and continuous improvement. 

AI-assisted development tools are a core part of how you work. You use them daily, critically, and effectively to improve the quality and speed of software delivery. 

You will report to a Domain Architect and work closely with senior engineering, product, and business leaders on AI initiatives and other high-impact challenges. 

You will contribute across the full lifecycle: problem definition, solution design, implementation, evaluation, deployment, monitoring, and production support. 

 

What you’ll do  

• Own the full loop - understand the problem, define the solution, architect it, ship it, monitor it. No one hands you a spec 

• Build with AI as your primary tool - Claude Code, Cursor, whatever gives the most leverage; do in a day what used to take a team a week 

• Co-design with stakeholders and the business - decision logic, risk thresholds, success metrics 

• Build the evaluation harness before you ship - if you can’t measure it, it’s not done 

• Own production from day one - monitoring, alerting, observability; you’re on call for what you build 

• Raise the bar - in design reviews, in code, and in how the team works 

 

Who you are  

Engineering  

• At least 7 years of experience as a backend engineer 
  
  
• Experience shipping production AI systems - running them in the real world and fixing what breaks, not just building them 

• Understanding of agentic architectures - orchestration, multi-step workflows, fallback and error logic 

• Strong eval instincts - you define metrics, build test sets, and don’t ship until you can measure 

• Full-stack range - comfortable across the prompt, RAG pipeline, orchestrator, and backend 

• Comfortable across any stack - you go where the right solution is 

• Honest communication - you flag problems early and give direct, candid feedback 

• You understand production concerns such as reliability, maintainability, security, observability, latency, and cost. 

AI fluency  

• Real fluency with AI coding tools - genuinely fast, not just "familiar with" 

• Think in workflows, not endpoints - agentic loops, skills, and orchestrated flows; CRUD with an LLM bolted on isn’t a system 

• Clear judgment about when to trust AI output and when to rewrite it 

• Goes beyond using AI - builds skills, workflows, and harnesses, not just prompts 

• You understand common AI-system risks such as hallucinations, prompt injection, data leakage, unreliable tool execution, and uncontrolled autonomy. 

Good to have  

• Fintech or regulated-environment experience - understanding why "probably fine" isn’t acceptable when money is moving 

 

What could set you apart  

• Builder’s itch. When you see a repetitive task or a problem the team has accepted as "too hard to fix," you come back with a working prototype. Watching people do manually what a system could do doesn’t sit right with you. 

• Grounded confidence. You move forward with incomplete information, make a call, own it. When you’re wrong, you update and move on - no drama, no ego. 

• Production instinct. When you design, you’re already thinking about 2am incidents, runaway inference costs, and edge cases that surface when real money is moving. "Probably fine" isn’t a risk posture. 

• Curious and adaptive. You explore new models and tools before anyone tells you to, run the experiment, and help create the best practices that don’t exist yet. 

 

Why join us 

• Real problems at scale - 25M+ customers in 190+ countries depend on these systems; the stakes are real 

• You help define the methodology - early-stage work at Payoneer; you won’t inherit a playbook, you’ll write it 

• Work directly with senior architects, engineers, product leaders, and business stakeholders. 

• Build solutions for challenging real-world problems where reliability, security, and measurable outcomes matter. 

 

#LI-LF1 

The Payoneer Ways of Working 

Act as our customer’s partner on the inside 

Learning what they need and creating what will help them go further. 

Continuously improve 

Always striving for a higher standard than our last. 

Do it. Own it. 

Being fearlessly accountable in everything we do. 

Build each other up 

Helping each other grow, as professionals and people. 

If this sounds like a business, a community, and a mission you want to be part of, apply today. 

We are committed to providing a diverse and inclusive workplace. Payoneer is an equal opportunity employer, and all qualified applicants will receive consideration for employment no matter your race, color, ancestry, religion, sex, sexual orientation, gender identity, national origin, age, disability status, protected veteran status, or any other characteristic protected by law. If you require reasonable accommodation at any stage of the hiring process, please speak to the recruiter managing the role for any adjustments. Decisions about requests for reasonable accommodation are made on a case-by-case basis.