Senior Software Engineer, Reliability

Responsibilities

• Own the reliability outcomes for customer-facing calls, voicemail, and activation, including connection, reachability, and audio quality.
• Make customer-visible change management explicit through reviewed, tested, and reversible production changes.
• Own deployment pipelines and the production-like staging tier used to validate application and call-path changes.
• Load-test the activation chain ahead of seasonal peak traffic.
• Build product-outcome observability, including funnels, SLOs, and meaningful alerting.
• Drive incidents to root cause across SIP signaling, media systems, Lambda services, and Postgres.
• Own incident reviews, failure ownership, runbooks, and regression tests.
• Partner with the reliability PM to turn diagnosis into an actionable engineering backlog.

Requirements

• 5+ years building and operating production backend or distributed systems where downtime affects real users.
• Strong AWS and infrastructure-as-code experience, including Terraform.
• Experience owning reliability practices such as SLOs, alerting, load testing, and incident reviews.
• Comfort with real-time and telephony systems, or strong willingness to learn SIP, RTP, and media behavior.
• Fluency using AI for diagnosis, analysis, and testing.
• Hands-on, scrappy approach to load testing and SIP trace analysis.
• Clear written and verbal communication skills.
• Collaborative, low-ego working style.
• Preferred: production FreeSWITCH, Kamailio, carrier SIP trunking, seasonal peak load testing, Postgres at scale, consumer hardware fleet operations, or Grafana experience.

Benefits

• Opportunity to work on technology intended to protect childhood and enable screen-free family communication.
• Ownership of the company’s primary reliability objective and technical direction.
• Small, high-trust, mission-driven team with meaningful influence from day one.
• Room to explore ideas and challenge assumptions while building systems aligned with trust, simplicity, and care.