Senior AI Engineer

Mytally; Lisboa; Hybrid; EUR 90,000 - 130,000; Full time

Job summary

Tally is hiring a Senior AI Engineer in Lisbon to help build AI-powered systems for our accounting platform. You will work across backend engineering and applied AI, taking ownership from experimentation to production.

You'll design AI agents and workflows, combine LLMs with deterministic logic, and continuously evaluate performance while shaping the AI architecture for scalable growth.

Qualifications

• Strong software engineering fundamentals for production systems (APIs, databases, distributed systems).
• Hands-on experience with LLMs, tool calls, or agentic workflows in production.
• Understanding nondeterministic systems, testing, and failure investigation.
• Pragmatic balance of AI use vs. traditional software for maintainability.
• Ability to own problems end-to-end and collaborate with engineers & domain experts.

Responsibilities

• Build AI agents and workflows using LLMs, tools, and structured data.
• Make AI production-ready with deterministic logic, validation, and oversight.
• Evaluate and improve AI performance, latency, and cost.
• Build the backend behind AI with APIs, integrations and long-running workflows.
• Shape AI architecture and tooling as the product grows.

Skills

Software engineering fundamentals

LLM experience

AI reliability

Problem solving

Ownership & collaboration

Job description

Lisbon · In-office, 5 days a week Full-time

As a Senior AI Engineer at Tally, you'll help build the AI-powered systems behind our accounting platform. You'll work across backend engineering and applied AI, taking ownership of solutions from experimentation to production.

About Tally

At Tally , we're building a modern accounting platform that helps SMEs spend less time managing their finances and more time running their businesses.

Accounting is full of repetitive, manual processes that are difficult to automate reliably. We're changing that by combining AI with solid software engineering practices to handle financial workflows from start to finish.

We're tackling complex engineering challenges, from processing financial documents to managing workflows that span weeks. We're building systems that businesses can trust with their finances, where accuracy, reliability, and traceability matter just as much as moving fast.

What You'll Work On

As a Senior AI Engineer at Tally, you'll help build the AI-powered systems behind our accounting platform. You'll work across backend engineering and applied AI, taking ownership of solutions from experimentation to production.

• Build AI agents and workflows: Design systems that use LLMs, tools, and structured data to automate complex accounting tasks.
• Make AI reliable in production: Combine LLMs with deterministic logic, validation, and human oversight to build systems that are accurate, traceable, and resilient.
• Evaluate and improve AI performance: Develop evaluation and testing practices, identify failure modes, and improve accuracy, latency, and cost.
• Build the backend behind AI: Develop APIs, integrations, and long-running workflows that connect AI capabilities to real financial processes.
• Shape our AI architecture: Help define how we design, monitor, test, and evolve AI-powered systems as the product grows.

What We're Looking For

• Strong software engineering fundamentals: Experience building and maintaining production systems, ideally with APIs, databases, and distributed systems.
• Hands-on LLM experience: You've built applications using LLMs, tool calling, or agentic workflows, and understand the challenges of taking them to production.
• AI evaluation and reliability: You understand how to test nondeterministic systems, measure their quality, and investigate failures.
• Pragmatic problem-solving: You know when to use AI, when traditional software is a better fit, and how to balance experimentation with maintainability.
• Ownership and collaboration: You can take a problem from idea to production, make technical decisions, and work closely with engineers and domain experts.

You don't need a machine learning research background or experience in accounting or fintech. We're looking for someone who understands how to turn AI capabilities into reliable software that solves real problems.

Our stack is evolving, particularly around AI. You'll have the opportunity to shape the tools, architecture, and practices we use to build reliable AI systems.

What to Expect

• This is an in-office position, 5 days a week, in Lisbon. We believe great early-stage teams are built in the same room.
• Our product is still early. Some things are rough, and there's plenty to figure out. That's part of the opportunity to make a real impact.
• You'll wear multiple hats, work beyond your usual responsibilities, and help wherever you're needed. That won't change anytime soon.
• We expect you to use AI tools to move faster, experiment, and focus on what matters. What counts is the quality of what you build, not how many lines of code you write.