Full Stack Senior Software Engineer

At Klaviyo, we value the unique backgrounds, experiences and perspectives each Klaviyo (we call ourselves Klaviyos) brings to our workplace each and every day. We believe everyone deserves a fair shot at success and appreciate the experiences each person brings beyond the traditional job requirements. If you're a close but not exact match with the description, we hope you'll still consider applying. Want to learn more about life at Klaviyo? Visit careers.klaviyo.com to see how we empower creators to own their own destiny.
About the Role
Our team is looking for Fullstack Engineers to lead key initiatives that will enhance our product offerings and support our company's growth. In this role, you'll play a crucial part in shaping outcomes by developing innovative end-to-end solutions using both front-end and back-end technologies. You'll optimize existing products and create new solutions that redefine what's possible for our customers.
As a Senior Engineer, you'll tackle complex challenges, develop multiple solutions, and evaluate business and technical trade-offs to determine the best path forward. You'll also act as a leader and mentor, and drive key technology decisions. Additionally, you'll be responsible for deploying well-designed, thoroughly tested solutions that ensure reliability and performance.
What We're Looking For

• A proven track record of building high-quality products and systems, with pride in writing clean, high-quality code.
• 7+ years of experience in a software engineering role.
• Strong experience developing end-to-end software solutions or extensive experience with both front-end and back-end technologies.
• Experience leading projects and being accountable for their outcomes.
• Experience mentoring team members or driving initiatives that help the team learn new skills.
• Experience conducting code reviews and running a robust testing cycle.
• Experience working in agile, fast-paced environments.

Nice to Have

• Skills with Python and related technologies
• Skills with React and related technologies
• Experience developing digital marketing or customer data software solutions.
• Experience with machine learning.
• Experience building cloud-native solutions, ideally with AWS.

Massachusetts Applicants:
It is unlawful in Massachusetts to require or administer a lie detector test as a condition of employment or continued employment. An employer who violates this law shall be subject to criminal penalties and civil liability.
The pay range for this role is listed below. Sales roles are also eligible for variable compensation and hourly non-exempt roles are eligible for overtime in accordance with applicable law. This role is eligible for benefits, including: medical, dental and vision coverage, health savings accounts, flexible spending accounts, 401(k), flexible paid time off and company-paid holidays and a culture of learning that includes a learning allowance and access to a professional coaching service for all employees.
Base Pay Range For US Locations:
$152,000 - $228,000 USD
Get to Know Klaviyo
We're Klaviyo (pronounced clay-vee-oh). We empower creators to own their destiny by making first-party data accessible and actionable like never before. We see limitless potential for the technology we're developing to nurture personalized experiences in ecommerce and beyond. To reach our goals, we need our own crew of remarkable creators-ambitious and collaborative teammates who stay focused on our north star: delighting our customers. If you're ready to do the best work of your career, where you'll be welcomed as your whole self from day one and supported with generous benefits, we hope you'll join us.
Klaviyo is committed to a policy of equal opportunity and non-discrimination. We do not discriminate on the basis of race, ethnicity, citizenship, national origin, color, religion or religious creed, age, sex (including pregnancy), gender identity, sexual orientation, physical or mental disability, veteran or active military status, marital status, criminal record, genetics, retaliation, sexual harassment or any other characteristic protected by applicable law.
IMPORTANT NOTICE: Our company takes the security and privacy of job applicants very seriously. We will never ask for payment, bank details, or personal financial information as part of the application process. All our legitimate job postings can be found on our official career site. Please be cautious of job offers that come from non-company email addresses (@klaviyo.com), instant messaging platforms, or unsolicited calls.
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