Back to jobs

Senior Fullstack Engineer - Americas

We are seeking talented Senior Fullstack Engineers to join our growing engineering team!

You’ll work on challenging problems, building scalable, robust services and user interfaces that drive the future of customer engagement technology. As our next great teammate, you'll blend your expertise across both backend and frontend systems, to directly impact the experience of a wide variety of customers, from startups to global enterprises, and help shape the features and infrastructure needed for our product to flourish.

Some things you'll do...

  • Design and develop high-performance, scalable services in Go and user interfaces in JavaScript (React & Ember), driving critical workflows that empower businesses to engage with their customers.
  • Collaborate cross-functionally with incredible partners across Product, Design, and Engineering to shape and implement features that enhance our platform and deliver seamless, intuitive experiences for our users.
  • Own the entire development lifecycle, from technical design through implementation and deployment, ensuring reliability, maintainability, and performance at scale.
  • Lead by example, mentoring your peers and contributing to a culture of shared knowledge, continuous learning, and technical excellence across the team.
  • Identify high-impact opportunities to improve both backend services and frontend interfaces, turning complex challenges into elegant, user-friendly solutions.
  • Influence product direction through technical insights, proactively collaborating with others to prioritize features that matter most.

What we're looking for...

  • 7+ years of professional experience in full-stack development, with a strong portfolio showcasing complex web applications and distributed systems.
  • Professional experience with TypeScript combined with advanced knowledge of JavaScript, CSS, and HTML.
  • Experience in modern JavaScript frameworks. (Bonus if you have experience with Ember.js or React)
  • Proficiency in backend technologies, ideally with Go or another strongly-typed language such as Java, Kotlin, or TypeScript. 
  • Experience designing and maintaining scalable APIs and services with relational (e.g., PostgreSQL or MySQL) or NoSQL databases.
  • A cloud-native mindset. Deep experience working in AWS, GCP, or Azure, or tools like Docker and Kubernetes are nice to have.
  • Passionate about building high-quality, testable code using unit, integration, and end-to-end testing to ensure system stability and performance.
  • A track record of collaborating effectively in a distributed team environment, with strong written and verbal communication skills and a commitment to mentoring others.
  • Problem-solving expertise, with the ability to transform complex technical challenges into simple, elegant solutions that delight users.
  • A DevOps approach to development, with experience in CI/CD pipelines, infrastructure automation, and monitoring production systems.
  • Demonstrated ability to influence product direction and contribute technical insights that help drive business value.

About Customer.io

Our mission at Customer.io is to power automated communication that people like to receive. Today over 7,300 internet businesses use Customer.io to manage, send, and track the performance of emails, SMS, push notifications, and in-app messages. Unlike typical marketing platforms, Customer.io helps businesses increase relevance by using behavioral data: what people do or don’t do when logged in to a web or mobile app.

We are offering a starting salary of $160,000 - $184,000 USD (or equivalent in local currency) depending on experience and subject to market rate adjustment.

Benefits at Customer.io include:

  • Unlimited PTO - we encourage at least 20 vacation days (in addition to holidays and sick days) so that you can unwind, unplug, and recharge
  • 16 weeks paid parental leave (including adoption and foster care)
  • 100% paid insurance premiums for you and your dependents
  • 401k retirement matching - up to 5% dollar-for-dollar match to retirement contributions
  • $1,500 annual healthy lifestyle budget (for gym memberships, classes, fitness equipment)
  • $250/monthly Remote Work Stipend to be used for home internet, cell phone, and other miscellaneous remote work costs
  • $300/month co-working space rental reimbursement
  • $2,000/yearly professional education budget for conferences, courses, workshops, books, etc.
  • $1,500 home office budget to make sure your working space is ergonomic and just what you need to do your best work!
  • One month sabbatical after five years at Customer.io
  • We also have opportunities to meet in person with your peers throughout the year

All final candidates will be asked to complete a background check and employment verifications as part of our pre-employment process.

Customer.io recognizes the stifling impact of systemic injustice on diverse communities. We commit to using our influence to increase inclusion and equity within the tech industry. We strive to build an inclusive team culture, implement bias-free hiring practices, and develop community partnerships to expand our global impact.

Join us!

Check out our careers page for more information about why you should come work with us! We are passionate about our core values of Empathy, Transparency, Responsibility, and Awkwardness and are looking for new coworkers to share and build that passion!

 

How to apply

Apply at the link below and tell us why you're interested in the position! ****We aim to respond to all applicants with a status update about your application, provided no technical issues or other limitations prevent us from doing so. Please keep an eye on your email for updates.

Here's what you can expect from our hiring process:

  1. 30 minute video call with a Recruiter
  2. Take Home Assignment + 2 60 minute Assignment Review Calls
  3. 60 minute Technical Deep Dive Interview
  4. Final Interview with Hiring Manager

Apply for this job

*

indicates a required field

Resume/CV*

Accepted file types: pdf, doc, docx, txt, rtf

Cover Letter

Accepted file types: pdf, doc, docx, txt, rtf

Select...

This should be the location you plan to consider your primary residence and are legally authorized to work in.

Select...
Select...
Select...

As a fully remote company, we don't have any requirements for where you live (wherever makes you happiest!), but that means we do not offer visa sponsorship at this time.

Voluntary Self-Identification

For government reporting purposes, we ask candidates to respond to the below self-identification survey. Completion of the form is entirely voluntary. Whatever your decision, it will not be considered in the hiring process or thereafter. Any information that you do provide will be recorded and maintained in a confidential file.

As set forth in Customer.io’s Equal Employment Opportunity policy, we do not discriminate on the basis of any protected group status under any applicable law.

Select...
Select...
Race & Ethnicity Definitions

If you believe you belong to any of the categories of protected veterans listed below, please indicate by making the appropriate selection. As a government contractor subject to the Vietnam Era Veterans Readjustment Assistance Act (VEVRAA), we request this information in order to measure the effectiveness of the outreach and positive recruitment efforts we undertake pursuant to VEVRAA. Classification of protected categories is as follows:

A "disabled veteran" is one of the following: a veteran of the U.S. military, ground, naval or air service who is entitled to compensation (or who but for the receipt of military retired pay would be entitled to compensation) under laws administered by the Secretary of Veterans Affairs; or a person who was discharged or released from active duty because of a service-connected disability.

A "recently separated veteran" means any veteran during the three-year period beginning on the date of such veteran's discharge or release from active duty in the U.S. military, ground, naval, or air service.

An "active duty wartime or campaign badge veteran" means a veteran who served on active duty in the U.S. military, ground, naval or air service during a war, or in a campaign or expedition for which a campaign badge has been authorized under the laws administered by the Department of Defense.

An "Armed forces service medal veteran" means a veteran who, while serving on active duty in the U.S. military, ground, naval or air service, participated in a United States military operation for which an Armed Forces service medal was awarded pursuant to Executive Order 12985.

Select...

Voluntary Self-Identification of Disability

Form CC-305
Page 1 of 1
OMB Control Number 1250-0005
Expires 04/30/2026

Why are you being asked to complete this form?

We are a federal contractor or subcontractor. The law requires us to provide equal employment opportunity to qualified people with disabilities. We have a goal of having at least 7% of our workers as people with disabilities. The law says we must measure our progress towards this goal. To do this, we must ask applicants and employees if they have a disability or have ever had one. People can become disabled, so we need to ask this question at least every five years.

Completing this form is voluntary, and we hope that you will choose to do so. Your answer is confidential. No one who makes hiring decisions will see it. Your decision to complete the form and your answer will not harm you in any way. If you want to learn more about the law or this form, visit the U.S. Department of Labor’s Office of Federal Contract Compliance Programs (OFCCP) website at www.dol.gov/ofccp.

How do you know if you have a disability?

A disability is a condition that substantially limits one or more of your “major life activities.” If you have or have ever had such a condition, you are a person with a disability. Disabilities include, but are not limited to:

  • Alcohol or other substance use disorder (not currently using drugs illegally)
  • Autoimmune disorder, for example, lupus, fibromyalgia, rheumatoid arthritis, HIV/AIDS
  • Blind or low vision
  • Cancer (past or present)
  • Cardiovascular or heart disease
  • Celiac disease
  • Cerebral palsy
  • Deaf or serious difficulty hearing
  • Diabetes
  • Disfigurement, for example, disfigurement caused by burns, wounds, accidents, or congenital disorders
  • Epilepsy or other seizure disorder
  • Gastrointestinal disorders, for example, Crohn's Disease, irritable bowel syndrome
  • Intellectual or developmental disability
  • Mental health conditions, for example, depression, bipolar disorder, anxiety disorder, schizophrenia, PTSD
  • Missing limbs or partially missing limbs
  • Mobility impairment, benefiting from the use of a wheelchair, scooter, walker, leg brace(s) and/or other supports
  • Nervous system condition, for example, migraine headaches, Parkinson’s disease, multiple sclerosis (MS)
  • Neurodivergence, for example, attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder, dyslexia, dyspraxia, other learning disabilities
  • Partial or complete paralysis (any cause)
  • Pulmonary or respiratory conditions, for example, tuberculosis, asthma, emphysema
  • Short stature (dwarfism)
  • Traumatic brain injury
Select...

PUBLIC BURDEN STATEMENT: According to the Paperwork Reduction Act of 1995 no persons are required to respond to a collection of information unless such collection displays a valid OMB control number. This survey should take about 5 minutes to complete.