Oxigen

We’re looking for a Finance Controller to take full ownership of financial operations in a fast-growing international business. This is a hands-on role from day one: you will build the function yourself, set up the systems, own the processes, and execute the work directly before any team exists around you.

We operate across multiple legal entities and currencies with significant transaction volume. The bar for accuracy, speed, and financial discipline is high. As the operation scales, you’ll have the opportunity to build and lead a finance team — but first, we need someone who can own it end-to-end.

Responsibilities

Invoicing & accounts

• Own the full invoicing process across all entities: issuing, tracking, reconciling, follow-ups
• Ensure invoices are accurate, on time, and properly recorded
• Manage AP/AR with zero tolerance for missed deadlines or errors

Payments & cash management

• Execute and oversee outgoing payments across entities and currencies
• Manage payment schedules and cash position
• Resolve payment issues quickly

Credit cards & financial services

• Own company credit cards: issuance, limits, reconciliation, policy
• Manage relationships with card providers and financial services vendors
• Improve tools/terms/fees when possible

P&L ownership

• Maintain and update P&L across all entities
• Track revenue, costs, margins with decision-ready detail
• Flag anomalies and variances early

Expense optimization

• Audit expenses regularly and find optimization opportunities
• Build/enforce an expense policy
• Reduce costs without slowing the business

Reporting & financial clarity

• Produce clear, accurate financial reports for leadership
• Keep documentation structured and audit-ready
• Work with external accountants/tax advisors and own the inputs/relationship

Systems & processes

• Choose, implement, and maintain finance tools
• Build SOPs for recurring processes so the function can scale
• Keep operations structured, documented, and resilient
   

Requirements

• 5+ years in a Finance Controller / Senior Finance / similar hands-on role
• Experience managing finances across multiple entities and currencies
• Strong command of USD operations, US finance, and international payments
• Proven P&L ownership and accurate reporting
• Experience with credit cards, payment providers, financial services vendors
• Hands-on operator (you do the work, not only oversee)
• Very detail-oriented, “zero mistakes” standard
• Proactive cost optimization mindset
• English C1+ (written and spoken)
• Able to choose and implement finance tools independently
   

Nice to have

• Built a finance function from scratch / early-stage experience
• Experience in fast-growing digital/online businesses
• Experience with banks, processors, payment rails
• Multi-entity consolidation / intercompany transactions exposure
   

What we offer

• Competitive salary + bonuses (per policy)
• 21 paid vacation days + 14 paid sick leaves
• Strong work-life balance
• Office in Warsaw available when you need it (snacks, coffee, etc.)
• Growth opportunities, multinational team environment, professional development support

About the project

US-founded media company operating email newsletters at scale – millions of subscribers across finance, health, and business verticals. Small engineering team, flat structure, direct ownership, fast iteration. No layers of approval, no large org to navigate.

You'll own the integration and infrastructure layer alongside a counterpart engineer who handles the AI and automation side. The AI systems depend on what you build staying reliable.
 

What you'll work on

• Custom CRMs and operational tools tailored to internal workflows
• Browser automation pipelines with Playwright for interacting with and validating UI workflows
• Distributed automation infrastructure: proxy management, session handling, request routing
• PostgreSQL data models and pipelines that AI systems and operational teams depend on
• Integrations with third-party APIs and platforms – including ones with inconsistent or undocumented APIs
   

Requirements

• 6+ years of backend development
• 4+ years of production Python
• Strong PostgreSQL: schema design, indexing, query optimization – not just ORM usage
• Hands-on Playwright or equivalent (Selenium, Puppeteer) for real browser automation
• Experience with proxy infrastructure: rotation, health checking, geographic routing
   

Tech stack

Python · FastAPI · PostgreSQL · Playwright · Docker · proxy infrastructure · REST APIs and webhooks · third-party platform integrations
 

Conditions

• B2B contract, full-time
• Warsaw office (onsite preferred, remote considered)
• Direct collaboration with technical PM and small senior team
• Fast-moving environment: ambiguity, shifting priorities, growing scope

About the project
 

US-founded media company operating email newsletters at scale – millions of subscribers across finance, health, and business verticals. Small engineering team, flat structure, direct ownership, fast iteration. No layers of approval, no large org to navigate.

You'll own the AI layer of the automation platform alongside a counterpart engineer who handles integration and infrastructure.
 

What you'll work on

• AI-driven content generation and management workflows at production scale
• Agent systems coordinating multi-step operational tasks: content, QA, validation, reporting
• RAG pipelines over internal knowledge bases and operational data
• Prompt architectures designed for reliability, cost control, and measurable output quality
• Evaluation and regression testing for LLM systems — "it looked fine when I tested it" isn't good enough
   

Real production systems, not demos. The work removes hours of manual operational work daily and needs to be reliable enough that people actually trust it.
 

Requirements

• 6+ years of development experience
• 4+ years of production Python
• 2+ years shipping production systems with LLMs and agents
• Solid understanding of what happens underneath the frameworks: tokenization, context windows, function calling, when RAG helps and when it doesn't
• Hands-on with agent orchestration: LangChain, LangGraph, MCP, or equivalent
• Clean, maintainable Python – frameworks support your thinking, not replace it
   

Tech stack

Python · FastAPI · PostgreSQL · LLM APIs (OpenAI, Anthropic) · LangChain / LangGraph / MCP · vector databases · Playwright · Docker · proxy infrastructure
 

Conditions

• B2B contract, full-time
• Warsaw office (onsite preferred, remote considered)
• Direct collaboration with technical PM and small senior team
• Fast-moving environment: ambiguity, shifting priorities, growing scope