Because you belong at Twilio.

The Who, What, Why and Where

Twilio is growing rapidly and seeking a Principal Machine Learning Engineer to join the Data Activation Products Machine Learning team. This organization is focused on designing and delivering customer-facing machine learning products at scale. We use Machine Learning to extract value from siloed data within the Twilio ecosystem and deliver Machine Learning API Prediction Services that can connect to multiple Twilio services as part of a cohesive and trusted system customers use to automatically improve engagement on Twilio channels. 

We are looking for a Principal Engineer who is experienced with Machine Learning systems at scale to be a proficient leader for multiple scrum teams during every step of our Machine Learning projects. This is a product-heavy focused role with expectations to guide model design based on product needs. You will be coding less and mentoring more! Someone with strong experience in python and Machine Learning is required. You are probably a machine learning generalist who has experienced different phases of a project. You’ve seen things that work and things that don’t and developed your own best practices based on these learnings. You're focused on using proven methods to deliver working prototypes that solve customer problems.

In this role you would… 

  • Work across multiple scrum teams to identify and manage intra-team dependencies, and ensure architecture decisions align with long term vision and roadmap.
  • The PE is expected to translate customer needs into modeling requirements and success criteria for a model in a minimum loveable product. You will do this by using your knowledge in Machine Learning to assist the Product team in defining models for new products based on customer’s needs and what is possible to achieve using available data and proven Machine Learning techniques. 
  • Participate in customer calls to gather customer use-cases for machine learning and design modeling requirements based on customer’s needs. 
  • Provide guidance to team members to ensure all models trained by the team meet the modeling requirements you defined and will bring value to the customer, solve the right problem, and follow machine learning best practices.
  • Deliver working proof of concept models and perform exploratory analysis to drive product research. 
  • Guide the team in blueprinting and in architecture and design decisions.
  • Establish team strategy and tools to enforce ethical use of data in machine learning,  and collaborate closely with legal and compliance teams to ensure that data handling in our models are compliant with legal and privacy restrictions. 

As a Principal Engineer on the DAP ML team at Twilio, you'll have the exciting opportunity to drive the state-of-the-art models and software that create our machine learning systems which are all backed by a literal torrent of real-time and historic data across Twilio's many communication channels. 

There is also additional opportunity in this role to participate in Machine Learning research, open source projects, obtain patents on innovative machine learning methods or technologies you develop, and contribute to Twilio’s vision for creating ethical and GDPR compliant data products. 


  • 7+ years of experience in ML modeling including supervised and unsupervised machine learning, deep learning, reinforcement learning, and/or statistical or mathematical modeling. Hands on experience developing, deploying and monitoring a large scale machine learning model in production.
  • Proven ability to design, deliver, and maintaining machine learning systems at scale, including testing and maintaining models in production such as A/B testing, retraining, and monitoring model performance.
  • Expert in best practices related to data cleaning, exploratory analysis, model training, model testing, model deployment, and maintaining quality machine learning APIs in production
  • Proven ability to bridge the gap between technical and business application 
  • Strong team leader. Enjoys mentoring and collaborating across engineering and product teams
  • Proficient in Python, Spark, and a deep learning framework (preferably pyTorch)
  • Proficient with at least one Cloud-Native infrastructure (AWS/Azure/GDP)
  • Experience with Kafka and airflow is a plus
  • Experience working in an agile team environment 
  • Approximately Ph.D. + 8 years of relevant experience, Masters + 10 years of relevant experience, BS + 11 years of relevant experience, but we consider candidates with varying years of experience based on proven history of leadership and execution on machine learning projects. 


You live the Twilio Magic values:

  • EMPOWER OTHERS: Be part of a small, high-impact and multi-talented engineering team. Show strong engagement in the team setting and collaborate across multiple disciplines.
  • WEAR THE  CUSTOMER’S SHOES: Passion for and demonstrated track record of executing product opportunities deeply grounded in customer needs
  • DRAW THE OWL: Self-starter who can see the big picture and prioritize work to make the largest impact
  • BE BOLD: Help us take one of the world’s most extensive communication data sets and transform it into cutting-edge AI applications and products that solve meaningful customer problems
  • BE INCLUSIVE: Collaborating and brainstorming product ideas with product managers, machine learning engineers, data scientists and software engineers
  • DON’T SETTLE: Experienced working at a massive scale with distributed, scalable systems, including making tradeoffs for consistency/availability
  • NO SHENANIGANS: Experience successfully applying data science and machine learning to real-world problems


The DAP ML team approaches machine learning projects with a developer mindset. We own the entire project from data collection and cleaning, model training, to deployment. The Machine Learning scrum teams consist of full-stack machine learning engineers who develop and maintain Inference APIs that deliver predictions from our trained ML models. We also collaborate closely with software and data engineering teams. DAP ML works closely with senior leadership and product teams to identify product opportunities and guide Twilio’s AI strategy. 

We have a strong belief that our people are the most important part of our business. We incorporate this philosophy into our practices and we live it every day. This means we have generous traditional benefits and take a lot of time to focus on quality management and leadership development. We also strive to ensure each person in the company is in the right job, knows how his or her job contributes to the overall company mission and has a clear sense of career growth and direction. We have great employee retention over the years because people love coming to work here and really feel like they're part of something special.


This position can be located in our Denver office with flexible options to work from home some days, or fully remote from almost any location. No matter where you are based, you will experience a company that believes in small teams for maximum impact; seeks well-rounded talent to ensure a full perspective on our customers’ experience,  understands that this is a marathon, not a sprint; that continuously and purposefully builds an inclusive culture that empowers everyone to do their best work and be the best version of themselves.

About us:

Millions of developers around the world have used Twilio to unlock the magic of communications to improve any human experience. Twilio has democratized communications channels like voice, text, chat, video and email by virtualizing the world’s communications infrastructure through APIs that are simple enough for any developer to use, yet robust enough to power the world’s most demanding applications. By making communications a part of every software developer’s toolkit, Twilio is enabling innovators across every industry — from emerging leaders to the world’s largest organizations — to reinvent how companies engage with their customers.

In accordance with applicable law, the following represents Twilio's reasonable estimate of the range of possible compensation for this role if hired in Colorado. Please note that this information is provided for those hired in Colorado only, and this role is open to candidates outside of Colorado as well. 


Denver/Boulder Metro:

Salary Range: $160,896 - $201,120

Rest of Colorado:

Salary Range: $140,784 - &175,980

Sales Commission: Additionally, this role is eligible to earn commissions and eligible to participate in Twilio's equity plan.

Non Sales: Additionally, this role is eligible to participate in Twilio's equity plan.

An overview of Twilio’s benefits offered is listed below:

Twilio is committed to delivering a comprehensive benefits program that provides support needed for you and your loved ones. It’s likely that you don’t think about benefits every day; however, they are an important component of your total compensation, and we want you to understand the options available to you so that you can make the most of your benefit dollars.  At the time of this posting, this role is eligible to participate in the following benefits, which Twilio reserves the right to modify at any time for any reason in accordance with applicable law:

Healthcare Insurance and Leave

  • Prescription Drug
  • Dental
  • Vision 
  • Flexible Spending and Health Savings Accounts
  • Leave programs for all of life’s moments: maternity, parental/bonding, as well medical leave to care for yourself or a loved one

Financial Benefits

  • Short and Long Term Disability Insurance
  • Life and Accidental Death & Dismemberment Insurance
  • 401(k) Retirement Savings Plan with a match

Reimbursement Programs & Stipends

  • $65 per month work-from-home stipend
  • Up to $50 per month for wellness expenses and activities
  • Up to $30 per month to use towards books/eBooks


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