Fourth is the world's largest and fastest-growing global leader of end-to-end restaurant and hospitality management technology solutions. We are looking for a senior, hands-on Lead AI Engineer to design, build, and productionize AI solutions used across Fourth's enterprise operations.

This role owns the technical foundations for AI in production - ensuring solutions are scalable, reliable, well-governed, and integrated with enterprise data and systems. You will report to the Director of Enterprise Data & Intelligence and sit at the forefront of reshaping how Fourth operates as a business, starting hands-on with production AI systems and growing into a standards-setting technical leader defining the architecture, governance, and direction for AI across the entire enterprise.

What's in it for you:

Enterprise-wide impact beyond a single product

Real ownership of production AI architecture and engineering decisions from day one

The challenge of connecting internal services, data platforms, and third-party systems into coherent, reliable AI solutions

Opportunity to set the standards and patterns as AI scales across Fourth

A high-visibility role in a fast-moving, technically ambitious team

Responsibilities:

Own AI engineering and architectural decisions across enterprise solutions - system design, integration patterns, API contracts, and trade-off reasoning

Design and build production-grade AI systems and pipelines; take solutions from prototype to reliable production

Define engineering standards, quality bars, and production readiness criteria

Shape feasibility, prioritisation, and technical approach for AI initiatives in partnership with the Director

Translate business problems into scoped, technically sound AI solutions

Review and harden solutions built by others; mentor junior AI engineers

Work with Data, Security, Legal, and Compliance on safe, governed AI delivery

Requirements:

5+ years of hands-on engineering experience, with at least 3 years owning production AI/ML systems end-to-end - not model development alone, but full delivery lifecycle including deployment and ongoing operations

Demonstrable experience making and owning architectural decisions: system design, integration patterns, and solution trade-offs - not just implementing designs handed to you by others

Hands-on production experience with LLM-based systems: RAG architectures, embeddings, vector search, and the operational realities of running LLMs at scale - latency, cost, failure modes, and observability

Strong Python engineering skills for production AI services; candidates with equivalent depth in other languages will be considered where AI engineering experience is strong

Hands-on CI/CD experience for AI/ML systems: automated testing, model validation, deployment pipelines, and rollback strategies

Cloud infrastructure ownership (Azure preferred): able to design and deploy, not just consume managed services; familiarity with containerisation and infrastructure-as-code

Track record of owning AI services post-deployment - not just shipping, but keeping them running reliably in production: monitoring, alerting, logging, and incident response

Experience defining technical standards and raising the quality bar across a team - not just individual delivery

Working knowledge of AI governance, access control, and responsible AI practices

Benefits and Culture:

25+ days off, as well as birthday day off and 4 charity days off per year

Flexible start and end of the working day and hybrid working mode

Team-centric atmosphere

Supplemental health insurance and healthy lifestyle support

New parents bonus scheme

*Only short-listed candidates will be contacted.
All personal data provided by you in your application will be processed by Fourth Bulgaria EOOD, UIC 203576042, solely for our recruitment purposes. If you do not provide your personal data, Fourth Bulgaria EOOD will not be able to review your application. Fourth Bulgaria will transfer your personal data only within its corporate group and to companies which provide recruitment support to Fourth Bulgaria. Fourth Bulgaria will ensure you can exercise your rights to access, correction and erasure of your personal data. More information on Fourth Bulgaria’s privacy policy for job candidates is available here and by applying you confirm that you have read it.

Our Story

In July 2019 Fourth joined forces with HotSchedules to become the global leader in end-to-end restaurant and hospitality management technology solutions. Together, the merged company now represents the world’s largest and only provider of end-to-end restaurant and hospitality management solutions for customers across the globe and of all sizes—from a single location or franchisee restaurant to a global restaurant or hotel chain. The combined company’s complete software-as-service (SaaS) solution suite including scheduling, time & attendance, applicant tracking, training, inventory management / procurement, HR / benefits and payroll services now serves customers in 120,000 locations worldwide and is supported by a dedicated, unified team across offices in the US, UK, Bulgaria, China, Australia, and UAE.

Fourth is an Equal Opportunity Employer

All qualified applicants will receive consideration without discrimination because of sex, gender identity, gender expression, sexual orientation, marital status, race, color, age, national origin, military status, religion, or disability or any other legally protected status.

Lead AI Engineer

Sofia

Lead AI Engineer

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