📍 Job Overview

• Job Title: Senior Site Reliability Engineer
• Company: Customer.io
• Location: Americas Remote
• Job Type: Full-Time
• Category: DevOps, Infrastructure
• Date Posted: 2025-06-21
• Experience Level: 10+
• Remote Status: Remote OK

🚀 Role Summary

• 📝 Enhancement Note: This role focuses on scaling infrastructure, improving reliability, and reducing operational toil for a high-scale messaging platform. It requires a strong background in SRE and a passion for making platforms better for developers and customers.

• Customer.io is seeking a Senior Site Reliability Engineer to help scale their infrastructure, reduce operational toil, and increase reliability as they grow. This role involves building and scaling infrastructure to support billions of messages per day, automating deployments and incident response, and collaborating across teams to debug and support systems in production.

💻 Primary Responsibilities

• 📝 Enhancement Note: The primary responsibilities of this role revolve around improving the reliability and performance of Customer.io's messaging platform, ensuring it can handle billions of messages per day and real-time events.

• 🔑 Key Responsibilities:

  • Build and scale infrastructure to support billions of messages per day and real-time events.
  • Automate deployments, alerting, and incident response to improve operational efficiency.
  • Tune MySQL and other datastore performance and improve reliability across distributed systems.
  • Collaborate across teams to debug, ship, and support systems in production.
  • Share knowledge and raise the bar through public sharing of progress, mentorship, and documentation.
  • Leverage AI tools to prototype, move faster, and make better decisions.

🎓 Skills & Qualifications

Education: A bachelor's degree in Computer Science, Engineering, or a related field. Relevant experience may be considered in lieu of a degree.

Experience: 7+ years in SRE or infrastructure roles, improving production systems at scale.

Required Skills:

• Deep MySQL experience, including schema design, performance tuning, and operational tooling.
• Fluency in cloud-native tech (GCP a plus) and Terraform.
• Proficiency in Go and Bash for scripting and systems programming.
• Skill in observability, incident response, and debugging distributed systems.
• A preference for action over perfection, and pride in owning technical decisions.

Preferred Skills:

• Experience with AI tools for prototyping, faster decision-making, and improving systems.
• Strong communication and collaboration skills, with a user-centric mindset.

📊 Web Portfolio & Project Requirements

• 📝 Enhancement Note: While not explicitly stated, a strong portfolio showcasing experience in SRE, infrastructure management, and system reliability would be beneficial for this role.

• Portfolio Essentials:

  • Documented case studies demonstrating experience in scaling infrastructure, improving reliability, and reducing operational toil.
  • Examples of automated deployments, alerting, and incident response processes.
  • Evidence of collaboration with cross-functional teams to debug, ship, and support systems in production.
  • Examples of public sharing of progress, mentorship, and documentation to raise the bar for team members.

Technical Documentation:

• Detailed documentation of system architecture, deployment processes, and server configuration.
• Evidence of performance metrics, optimization techniques, and testing methodologies.
• Code comments and quality standards demonstrating attention to detail and best practices.

💵 Compensation & Benefits

Salary Range: $140,000 - $180,000 USD per year, depending on experience and subject to market rate adjustment.

Benefits:

• 100% coverage of medical, dental, vision, mental health, and supplemental insurance premiums for you and your family.
• 16 weeks paid parental leave.
• Unlimited PTO.
• Stipends for remote work and wellness.
• A professional development budget.
• View full benefits package here

Working Hours: Full-time, with flexible hours and a focus on results and impact.

🎯 Team & Company Context

🏢 Company Culture

Industry: Customer.io operates in the marketing technology industry, focusing on automated communication that people actually want to receive.

Company Size: Medium (7,500+ companies use their platform, with a growing customer base).

Founded: 2010, with a history of steady growth and innovation in the marketing automation space.

Team Structure:

• The SRE team works closely with engineering, product, and design teams to ensure the reliability and performance of Customer.io's messaging platform.
• The team is expected to collaborate and share knowledge across functions to improve the overall customer experience.

Development Methodology:

• Customer.io follows Agile methodologies, with a focus on continuous integration, continuous deployment, and regular iteration.
• The team uses Go, React, Ember, and AI to ship fast and scale with confidence.

Company Website: customer.io

📝 Enhancement Note: Customer.io values ownership, engineers with product taste, and a healthy skepticism for "the way things are done." They prioritize action, forward motion, and continuous learning.

🌐 Work Environment

Office Type: Remote-first, with a strong focus on asynchronous communication and collaboration.

Office Location(s): Americas Remote.

Workspace Context:

• Customer.io provides the necessary tools and resources for remote work, including multiple monitors and testing devices.
• The company encourages a collaborative work environment, with regular team meetings and open communication channels.
• Customer.io values work-life balance and offers flexible working hours to accommodate individual needs.

Work Schedule: Full-time, with flexible hours and a focus on results and impact. The work schedule is designed to accommodate varying time zones and personal needs.

📝 Enhancement Note: Customer.io's remote work environment allows for greater flexibility and work-life balance, while still fostering a collaborative and inclusive team culture.

📄 Application & Technical Interview Process

Interview Process:

• Application review.
• Recruiter call (30 minutes) to discuss the role and company culture.
• Behavioral interview (60 minutes) with a hiring manager, focusing on ownership, product thinking, and collaboration.
• Take-home assignment to complete a short, realistic task similar to what would be worked on at Customer.io.
• Technical interview (90 minutes) to review the take-home assignment and collaborate on a system design problem, focusing on real-world scaling challenges and tradeoffs.

Portfolio Review Tips:

• Highlight experience in scaling infrastructure, improving reliability, and reducing operational toil.
• Showcase automated deployments, alerting, and incident response processes.
• Demonstrate strong communication and collaboration skills, with a user-centric mindset.
• Emphasize attention to detail and best practices in code quality and documentation.

Technical Challenge Preparation:

• Brush up on Go, Bash, and cloud-native tech (GCP a plus) skills.
• Familiarize yourself with MySQL, Terraform, and AI tools for prototyping and decision-making.
• Practice system design problems, focusing on real-world scaling challenges and tradeoffs.

ATS Keywords: (See the comprehensive list below)

🛠 Technology Stack & Web Infrastructure

Backend & Server Technologies:

• MySQL (deep experience required)
• Cloud-native tech (GCP a plus)
• Terraform (fluency required)
• Go (proficiency required)
• Bash (proficiency required)

Development & DevOps Tools:

• AI tools for prototyping, faster decision-making, and improving systems (preferred)
• Observability and incident response tools (required)
• Collaboration and communication tools (required)

📝 Enhancement Note: Customer.io's technology stack focuses on cloud-native technologies, AI tools, and open-source solutions to ensure the reliability and performance of their messaging platform.

👥 Team Culture & Values

Web Development Values:

• Ownership: You own problems end to-end, moving fast, acting like an owner, and thriving in ambiguity.
• Engineers with product taste: You think like a user, not just an engineer, focusing on performance, reliability, and user experience.
• A healthy skepticism for "the way things are done": You bring rigor and creativity, prioritizing forward motion and continuous learning.

Collaboration Style:

• Customer.io values cross-functional collaboration, with a focus on clear communication, regular team meetings, and open feedback channels.
• The company encourages knowledge sharing, technical mentorship, and continuous learning to raise the bar for the entire team.

📝 Enhancement Note: Customer.io's team culture emphasizes ownership, product thinking, and continuous learning, with a strong focus on collaboration and knowledge sharing.

⚡ Challenges & Growth Opportunities

Technical Challenges:

• Scaling infrastructure to support billions of messages per day and real-time events.
• Automating deployments, alerting, and incident response to improve operational efficiency.
• Tuning MySQL and other datastore performance and improving reliability across distributed systems.
• Collaborating across teams to debug, ship, and support systems in production.
• Leveraging AI tools to prototype, move faster, and make better decisions.

Learning & Development Opportunities:

• Continuous learning and skill development in cloud-native technologies, AI tools, and open-source solutions.
• Conference attendance, certifications, and community involvement to stay up-to-date with industry trends and best practices.
• Technical mentorship, leadership development, and architecture decision-making opportunities as the team grows and evolves.

📝 Enhancement Note: Customer.io offers numerous challenges and growth opportunities for experienced SRE professionals looking to make a significant impact on a high-scale messaging platform.

💡 Interview Preparation

Technical Questions:

• Be prepared to discuss your experience in scaling infrastructure, improving reliability, and reducing operational toil.
• Brush up on your knowledge of MySQL, cloud-native tech (GCP a plus), Terraform, Go, and Bash.
• Familiarize yourself with AI tools for prototyping, faster decision-making, and improving systems (preferred).
• Practice system design problems, focusing on real-world scaling challenges and tradeoffs.

Company & Culture Questions:

• Research Customer.io's history, mission, and values to demonstrate your understanding of the company and its culture.
• Prepare thoughtful questions about the team, the role, and the company's long-term goals to showcase your interest and engagement.

Portfolio Presentation Strategy:

• Highlight your experience in scaling infrastructure, improving reliability, and reducing operational toil.
• Showcase automated deployments, alerting, and incident response processes.
• Demonstrate strong communication and collaboration skills, with a user-centric mindset.
• Emphasize attention to detail and best practices in code quality and documentation.

📝 Enhancement Note: Customer.io values action over perfection, so be prepared to discuss your approach to problem-solving, decision-making, and continuous learning.

📌 Application Steps

To apply for this Senior Site Reliability Engineer position:

• Submit your application through the application link provided.
• Customize your portfolio with live demos and responsive examples, highlighting your experience in scaling infrastructure, improving reliability, and reducing operational toil.
• Optimize your resume for SRE and infrastructure roles, emphasizing project highlights and technical skills.
• Prepare for the technical interview by practicing system design problems and brushing up on relevant technologies.
• Research Customer.io's company culture, values, and long-term goals to demonstrate your understanding and engagement.

📝 Enhancement Note: Customer.io's application process is designed to be clear, human, and informative, with a focus on helping both the candidate and the company make an informed decision.

🛑 Important Notice: This enhanced job description includes AI-generated insights and industry-standard assumptions. All details should be verified directly with the hiring organization before making application decisions.

🔑 ATS Keywords

Programming Languages:

• Go (proficiency required)
• Bash (proficiency required)
• MySQL (deep experience required)

Web Frameworks & Libraries:

• Cloud-native tech (GCP a plus) (fluency required)
• Terraform (fluency required)

Server Technologies:

• MySQL (deep experience required)
• Cloud-native tech (GCP a plus) (fluency required)

Databases:

• MySQL (deep experience required)

Tools:

• AI tools for prototyping, faster decision-making, and improving systems (preferred)
• Observability and incident response tools (required)
• Collaboration and communication tools (required)

Methodologies:

• Agile methodologies (required)
• Continuous integration, continuous deployment (required)

Soft Skills:

• Ownership (required)
• Product thinking (required)
• Collaboration (required)
• Communication (required)
• Problem-solving (required)
• Decision-making (required)
• Continuous learning (required)

Industry Terms:

• Site Reliability Engineering (required)
• Infrastructure Management (required)
• System Reliability (required)
• Cloud-native Technologies (required)
• Terraform (required)
• Go (required)
• Bash (required)
• Observability (required)
• Incident Response (required)
• Debugging (required)
• Distributed Systems (required)
• Automation (required)
• Performance Tuning (required)
• Documentation (required)
• AI Tools (preferred)