Principal, Machine Learning Engineer (L5)

Twilio is hiring a Principal Machine Learning Engineer for its Customer Memory Team, focused on building foundational AI and ML capabilities that support intelligent engagement. This remote role is designed for engineers who want to connect research ideas to production experimentation, enabling contextual intelligence by identifying customers, understanding their history, and selecting the best way to reach them.

In this position, you will help shape core functionality in a fast-moving product with rapid adoption. You will translate ambiguous starting points into rigorous experiments that can be executed within weeks, while also deep-diving into modern approaches such as LLM orchestration, retrieval strategies, and data-driven personalization. You will also ensure the ML systems you build can perform reliably at Twilio scale.

What you’ll do

• Deliver new functionality within a product environment that moves quickly and sees rapid adoption.
• Turn nebulous ideas into well-defined, experiment-driven plans, executed in weeks.
• Perform deep-dive research into state-of-the-art LLM orchestration, retrieval strategies, and data-driven personalization.
• Build machine learning systems that hold up at large scale.
• Continuously learn and adapt in a fast-paced, high-delivery environment.
• Proactively adopt and integrate the latest AI development stacks to reduce boilerplate and focus on core differentiation.

What you bring

• 10+ years of applied ML/AI experience, with a record of owning technically ambitious systems end to end.
• Comfort operating in a 0-to-1 setting with ambiguous requirements and a strong bias for action.
• Proficiency in Python.
• Experience building cloud-based services on AWS, GCP, or Azure, including high-volume data, streaming or real-time inference paths, and varied data stores.
• Deep expertise in production-grade ML/AI architecture, deployment, and systems, including LLM orchestration, embedding models, and vector stores.
• Strong fundamentals in statistical machine learning, transformer models, and LLMs.
• Ability to raise the technical bar through mentorship, design review, and engineering standards without formal management authority.
• Experience building cloud services using AWS, GCP, or Azure.
• Strong communication skills and a track record as an effective collaborator.
• Experience building autonomous agents that support multi-turn conversations and long-term context or consistency.
• Background in predictive modeling on user behavior, including experiment design and the causal or counterfactual methods needed when randomization is partial.
• Prior experience working with a globally distributed team.

Location and travel

This role is remote, based in India (Karnataka, Tamil Nadu, Telangana State, Maharashtra, and New Delhi). Travel may be required occasionally for in-person project or team meetings.

Benefits

• Competitive pay
• Generous time off
• Ample parental and wellness leave
• Healthcare
• Retirement savings program

How Twilio works in hiring

• Twilio uses Artificial Intelligence to help make the hiring process more efficient.
• Every hiring decision is made by real Twilions.
• While remote-first, you may be asked to report in person occasionally for team gatherings, functional off-sites, or customer meetings.

Fraud warning

Scammers may impersonate Twilio recruiters with fake job postings, emails, websites, or messages. Ensure you use an official @twilio.com email address. Twilio will never ask for payment, gift cards, cryptocurrency, or banking information during recruiting. Job offers are not made without a formal interview process and interviews are not conducted exclusively through text-based messaging apps.