AI Engineer (Onsite)

Viktor; Województwo mazowieckie; On-site; PLN 80,000 - 120,000; Full time

Job summary

Viktor is looking for a talented developer to enhance their AI agent's capabilities in Warsaw. In this role, you'll design and build the core runtime for the agent, facilitate integrations with popular tools, and manage infrastructure effectively. You’ll work closely with the founders and have a significant impact on the direction of the product. The position is hybrid, expecting regular office presence, and offers competitive salary and equity.

Qualifications

• Experience in AI-assisted development and tool integration.
• Ability to design systems that scale and understand trade-offs.
• Your work will directly impact user experience and customer satisfaction.

Responsibilities

• Build the agent runtime with sandboxed execution and tool orchestration.
• Ship integrations with various tools based on customer requests.
• Maintain and run infrastructure, ensuring efficiency and cost-effectiveness.
• Develop product features that are immediately usable by customers.

Skills

Agentic coding

Systems thinking

Speed

Range

Genuine interest in AI

Tools

TypeScript

React

Python

Job description

Viktor is the AI coworker. It lives in Slack and Microsoft Teams, connects to thousands of tools, and does real work for real companies: finance, marketing, ops, engineering. We're building the product that replaces half the SaaS stack with a single teammate.

The team is small. The scope is not.

The Role

Here's what building Viktor is like: someone in Slack asks Viktor to reconcile their Stripe payouts against their books. Viktor does it, live, in under a minute. The customer tells their network. Two more teams sign up that week.

Your job is to make Viktor do more of those things, for more customers, more reliably. That's the job. Build the agent everyone else will try to copy.

Warsaw is where product, growth, and engineering sit in the same room. You'll build next to the people who talk to customers every day, work directly with both founders, own a real surface of the product, and see your code in production the same day you wrote it.

What You'll Do

• Build the agent runtime. Sandboxed execution, tool orchestration, memory. The part of Viktor that turns a sentence in Slack into a real action against a real API.
• Ship integrations. We connect to thousands of tools. Salesforce, Notion, Stripe, QuickBooks, HubSpot, Shopify, whatever customers ask for next. OAuth, webhooks, schema mapping, error handling. Each new integration unlocks a new shape of customer.
• Run the infrastructure. Viktor handles 600K+ tool calls a day. Container orchestration, autoscaling, cost per task. You're the reason it stays fast and cheap.
• Ship product. Features that go directly to users through Slack and Teams. You'll see people using what you built within hours.
• Whatever needs building. Small team, large surface. You'll work on things that aren't in this document.

How You'll Know You're Succeeding

You're shipping to production every day, and the changelog has your name on it.

A feature you built is the reason a customer closed.

When Viktor breaks at 3am, you can fix it because you understand the system end to end.

Founders are writing less code because you've taken over surfaces they used to own.

What We're Looking For

• Agentic coding. You're fully bought into AI-assisted development. Agents, parallelized workflows, whatever tools make you fastest. If that isn't already how you work, you'll be behind on day one.
• Systems thinking. You make hard technical trade-offs and own them. You understand how things break at scale and design for it. Good judgment about what's worth doing well and what's worth doing fast.
• Speed, with the bar up. You ship today, not Thursday. No enterprise engineering. No three-week review cycles.
• Range. You can go from the agent runtime to a React component to a deployment script in an afternoon. Viktor's surface area is too big for specialists.
• Genuine interest in how AI actually works. You've read papers. You've read other people's prompts. You have opinions about how evals should work.
• Warsaw-based. Hybrid. You'll be in the office regularly alongside the rest of the team.

Bonus

• Previous AI engineering experience: agents, harnesses, deep model understanding.
• Previous founder or early-stage builder. You've worn every hat and liked it.
• Open source contributions to the AI tooling we live in.

Tech

TypeScript/React on the frontend. Python on the backend and agents. Modal for infrastructure. You don't need to know all of it coming in. You need to learn fast.

How we work

Small team, high trust, low process. Decisions are made by owners, not committees. You will ship your first week. You will talk to users your first day. We don't do alignment meetings or stakeholder syncs. We build things, see if they work, and iterate.

Everyone here owns something real. Not a task. A surface of the company that customers depend on. When it breaks, you fix it. When it wins, everyone knows whose work it was.

We use Viktor to build Viktor. You'll see what you're working on in action every day.

Why Viktor

This is a rare window. The product works. The market is pulling. The team is small enough that what you do next week will be live in production next week. That doesn't last forever. Right now, it's still true.

Compensation

Competitive salary, meaningful equity, and the kind of ownership that only exists at this stage.

We're in Munich, New York, and Warsaw. Onsite preferred. The best work happens when you're in the room.