AI Software Engineer for Siri - Machine Learning & GenAI Innovation

Further Details

Seeking a skilled Software Engineer with expertise in Machine Learning and GenAI to enhance Siri's capabilities for UK English users. This position involves developing and deploying advanced LLM-based solutions, focusing on natural language understanding, response generation, and culturally resonant user experiences. As a technical anchor for the market, you will lead work streams in designing and implementing large-scale ML and AI systems. The role sits at the intersection of ML, Data, and Software Engineering, requiring a blend of advanced coding skills and a deep understanding of ML concepts for production environments. This is a pivotal role within a dynamic team, dedicated to making Siri a truly global and intuitive assistant. Successful applicants will contribute to groundbreaking research and development in AI, driving innovation and ensuring Apple's commitment to inclusivity and accessibility.

Software Engineer - Siri AI Innovation

An exceptional opportunity awaits a skilled Software Engineer focused on Machine Learning and Generative AI, contributing to the evolution of Siri. This role is pivotal in shaping the user experience for hundreds of millions worldwide by enhancing Siri’s understanding and responsiveness in UK English. You will work on cutting-edge AI technologies, including advanced LLMs, to deliver highly personalized and culturally attuned interactions.

As a key technical lead for the UK English market, you will spearhead the design and implementation of large-scale AI systems, driving innovation at the intersection of ML, Data, and Software Engineering. This position offers the chance to develop robust, production-ready AI solutions and influence the global direction of Apple's voice assistant technology.

• Job Title: AI Software Engineer (Siri)
• Location: Catalunya, Spain
• Key Technologies: Machine Learning, Generative AI, Large Language Models (LLMs), NLP
• Focus Areas: Speech Recognition, Natural Language Understanding, Response Generation, Data Experimentation, Scalable Software Engineering
• Career Growth: Opportunity to work on global AI products with significant user impact.

Skills

• Professional-level fluency in English
• Deep familiarity with UK or other English-speaking regional culture and idiom
• Experience applying machine learning and NLP techniques to products
• Solid understanding of ML concepts
• Strong skills in software design and programming across different paradigms
• Experience contributing to large production code bases
• Experience working with data at scale
• Building or curating datasets
• Analyzing results
• Making data-driven decisions
• Hands-on experience with large language models (LLMs): fine-tuning, prompt and context engineering, evaluation, and inference optimization
• Agentic systems, tool calling, or retrieval-augmented generation experience
• Experience with speech technologies (ASR, TTS, pronunciation modeling)
• Adapting models or products across languages and markets
• Multilingual and cross-lingual modeling, transfer learning, or low-resource settings
• Ability to formulate research problems, design, experiment, implement and communicate solutions
• Product focus with strong emphasis on end-user experience
• Software development in Python, Swift, Objective-C, C++ or C
• Experience on Apple platforms preferred

Duties and Responsibilities:

• Play a part in the next revolution of machine learning technology
• Teach Siri new languages and improve its capabilities
• Own the product end-to-end: Speech Recognition, NLP, and Response
• Employ advanced Large Language Models (LLMs)
• Adopt models for global markets
• Run data experiments
• Engineer scalable software for personalized experiences
• Craft innovative, end-to-end solutions for millions of customers
• Act as the technical anchor for the UK English speaking market
• Lead work streams to design and implement large-scale ML and GenAI solutions
• Advance customer experience through AI development
• Leverage large language models (LLMs) and agentic approaches
• Build real-world systems using data generation methods
• Work with partner teams across Apple
• Share expertise and bring architectural proposals accounting for international market nuances
• Ensure Siri feels genuinely native to English users
• Build the foundation of Siri AI for users around the world

How to apply

• Application Link: Please visit the provided link to submit your application.
• Target Role: Basic Language Engineer (British English) for Siri in Catalunya, Spain.
• Company: JR Spain Client / Employer: Lex.
• Key Skills Required: Professional English fluency, ML/NLP experience, strong software design and programming skills, experience with large-scale data, and hands-on LLM experience are essential.
• Additional Skills: Familiarity with speech technologies and adapting models for diverse markets is preferred.
• Application Deadline: Ensure your application is submitted before 18th December 2026.
• Job Reference: 466553260860663398432460.
• EU Work Permit: Please note that an EU work permit is required for this position.