Senior Software Engineer - SMS Delivery (Full Stack - Front End)

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 Team

The SMS Mobile team at Klaviyo is responsible for empowering the over 250,000 Ecommerce clients we work with on a global scale to deliver effective experiences on mobile devices. This team focuses on performance optimization and continuous development of our Mobile Marketing Channels (SMS and Push Notifications), Mobile SDKs (IOS and Android), and Klaviyo's own mobile applications. While Email was how Klaviyo began, SMS is truly the way of the future. As a result of this, we put a lot of emphasis around keeping the client experience top of mind while making sure our mobile applications are able to scale at large for many of today's fastest growing brands.

About The Role

The SMS Delivery team is responsible for making sure that the messages that our clients send get sent through the right platform (Klaviyo), through the correct Carrier (AT&T, Verizon, etc), while also making sure that the message is delivered via the right device (Phone or mobile). In addition to this, there is always an eye towards compliance to make sure that the messages being sent and delivered are legal. Ultimately making sure that from signup to send, the experience is seamless.

How You Will Make An Impact

Our SMS Delivery team is a team and works closely with our four other mobile teams which are focused on building long lasting relationships with our clients and their audiences through SMS conversations and deliverability pipeline while keeping an eye on new market opportunities while optimizing our SMS Platform. Incoming members to the SMS Delivery team will be responsible for building the foundation of how we scale internally at Klaviyo. In this front end-leaning full stack role, you will have an opportunity to make a major impact on the direction and priorities of the team. You will be responsible for building and managing Klaviyo’s Customer Facing Mobile Application (with an emphasis on frontend development) while also focusing on internal tooling working with various stakeholders across the company.

Technologies We Use (not Exhaustive)

• HTML, TypeScript, JavaScript, React, Backbone.js
• Python, Django, Celery
• MySQL, Cassandra, RabbitMQ, Redis
• Amazon Web Services (EC2, RDS, Aurora, etc.), Terraform, Ansible, Packer, and other DevOps tools

What We Are Looking For

• 5-7+ years of experience in a software engineering discipline
• Significant experience with full stack application development
• Experience working with both monolithic and microservices architectures
• Experience with creating and refactoring databases that can withstand high query volumes
• Experience with CI/CD pipelines
• Experience debugging performance issues and improving application performance
• Proven experience with being a coach and a mentor for team members and helping them grow
• Excellent verbal and written communication skills.
• Excellent organizational skills and attention to detail.
• Excellent time management skills with a proven ability to meet deadlines.
• Strong analytical and problem-solving skills.
• Strong supervisory and leadership skills.
• Ability to prioritize tasks and to delegate them when appropriate.
• Ability to function well in a high-paced and at times stressful environment.

Nice to Have

• Experience creating new applications with scalability in mind
• Exposure to large-scale system design
• Experience with AWS or any similar cloud provider

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.

Pay Range For US Locations:
$156,800—$235,200 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.

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