Senior Software Engineer (L3)

Twilio delivers communications solutions that enable businesses and developers to create personalized customer experiences. The Senior Software Engineer will design, build, and operate scalable platform services for phone numbers and KYC compliance, including APIs, microservices, and tooling. The role also involves AI-augmented development, cross-functional collaboration, technical ownership, mentoring, and incident management.

Responsibilities:

• DRAW THE OWL: Contribute significantly to the technical design and roadmap for core platform components, authoring technical specifications and driving execution to transition legacy systems into modern, scalable cloud-native microservices
• ACCELERATE WITH AI: Actively leverage AI coding assistants (GitHub Copilot, Anthropic Claude, or internal LLMs) to automate boilerplate, generate comprehensive test suites, and rapidly prototype solutions. Set an example within the team for amplifying individual velocity while maintaining high standards of code quality and safety guardrails
• BE AN OWNER: Drive technical excellence and end-to-end component ownership within your team, making sound technical decisions that balance rapid feature delivery with system reliability, security, and technical debt reduction
• WEAR THE CUSTOMER’S SHOES: Partner with Product Managers and cross-functional stakeholders to translate customer needs and regulatory requirements into precise technical specifications, developer-first APIs, and seamless application workflows
• EMPOWER OTHERS: Mentor and uplift junior engineers (L1–L2), onboard new team members, and foster a collaborative environment through constructive code reviews, tech talks, and technical guidance
• RUTHLESSLY PRIORITIZE: Proactively identify and resolve technical risks, performance bottlenecks, and security vulnerabilities within team services. Fully own on-call responsibilities, driving incident resolution and following through with durable root-cause remediation
• WRITE IT DOWN: Articulate technical designs, system trade-offs, and operational runbooks clearly to your team and cross-functional partners through high-quality design documents, RFCs, and thorough documentation

Requirements:

• 5+ years of experience designing and developing highly available, high-scale, secure, mission-critical cloud-native enterprise distributed systems
• Strong Proficiency in Java or Go, with solid knowledge of AWS ecosystems (Lambda, EKS, DynamoDB, Kafka)
• Hands-on experience with cloud-native infrastructure (AWS preferred), microservices patterns, and building highly resilient systems
• Practical experience using AI tools (e.g., Copilot, Claude, Cursor) to accelerate software delivery
• You should be comfortable discussing how you use LLMs for debugging, code synthesis, and prototyping
• Experience building and maintaining high-volume public-facing APIs with a focus on developer experience
• Experience with high-throughput data processing and storage solutions (SQL/NoSQL, Redis, Kafka, or Spark)
• Familiarity with Kubernetes, Terraform, and modern CI/CD paradigms
• Demonstrated ability to influence technical decisions within your team through strong communication and technical credibility
• Experience building "internal platforms" that enable other developer teams to move faster
• Experience building or integrating AI agents into internal developer platforms or automated ops workflows