Sr Backend Engineer

Senior Software Engineer

You'll join Slang's Engineering team as a Senior Software Engineer, contributing across our core product areas including telephony infrastructure, real-time voice AI, and application functionality. Your work will help restaurants automate customer interactions and improve service through natural conversation. You'll spend roughly 90% of your time developing backend services. Our backend is written in Kotlin, but prior Kotlin experience is not required; strong fundamentals in any object-oriented language will set you up to ramp quickly. You'll make occasional contributions to React/TypeScript frontend features as needed. Your work will directly impact thousands of restaurant interactions daily, helping businesses streamline operations and deliver better customer experiences.

You'll report to the Director of Engineering & Data, collaborating closely with product managers, conversation designers, and fellow engineers. As a senior engineer, you'll own features end to end and help shape technical direction for your pod, not just execute against a spec. The role includes key ceremonies: daily standups at 1:00 PM ET, bi-weekly cycle planning, and weekly Show & Tell sessions. You'll use modern collaboration tools like Slack, GitHub, and video conferencing to stay connected with the team. You'll mentor junior and mid-level engineers through code reviews and pair programming, and set the quality bar others build on.

Our engineering culture emphasizes pragmatic solutions, continuous learning, and collaborative problem-solving. We believe in domain-driven design, comprehensive testing, and building systems that gracefully handle the complexities of real-world restaurant operations. You'll work alongside engineers who care about reliable, scalable conversational experiences and who regularly share knowledge through Show & Tell sessions and detailed technical documentation.

As a senior engineer, you'll go deep on conversational AI, telephony at scale, and modern cloud-native architectures while taking ownership of architectural decisions and technical standards. You'll pick up Kotlin and functional programming patterns on the job while working on production systems that handle real-time voice interactions. The cross-functional nature of the role, and the scope you'll own, sets you up to grow toward staff-level and technical leadership work: driving design across services, influencing the roadmap, and raising the bar for the engineers around you.

What Success Looks Like

• Design and implement scalable backend services following domain-driven design principles, with comprehensive error handling and testing
• Drive technical design for features you own, and help shape architecture across the services your pod touches
• Develop and maintain GraphQL APIs that efficiently serve both internal and external clients
• Create robust integrations with our telephony (Twilio/Telnyx) and voice AI stack, handling edge cases and failure scenarios gracefully
• Design efficient Firestore data models that balance performance, cost, and maintainability
• Implement comprehensive observability including logging, metrics, tracing, and actionable alerting
• Deliver production-ready code with appropriate test coverage (unit, integration, and end-to-end)
• Lead code reviews, providing constructive feedback and raising the quality bar for the team
• Document technical decisions, API contracts, and system architecture clearly
• Deploy containerized applications to Google Cloud Platform following cloud-native best practices
• Occasionally build or update React/TypeScript frontend components for restaurant staff and customers
• Shape coding standards and best practices, and mentor junior and mid-level engineers as they grow

What You Will Bring

Required Qualifications:

• 5+ years of professional software development experience, primarily in backend systems
• Strong proficiency in at least one object-oriented language (e.g., Java, Kotlin, C#, Python, TypeScript, Ruby, C++, Go), with a solid grasp of OO design principles and willingness to work day-to-day in Kotlin
• A track record of owning features end to end and mentoring less-experienced engineers
• Experience building and consuming RESTful or GraphQL APIs
• Familiarity with NoSQL databases and data modeling concepts
• Experience with containerization (Docker) and cloud platforms (GCP, AWS, or Azure)
• Strong understanding of software testing practices and test-driven development
• Excellent debugging and troubleshooting skills
• AI fluency: you actively use AI tools in your daily engineering work, not just awareness of them. We're AI native, and we expect the same of our engineers
• Basic familiarity with React and TypeScript (occasional frontend adjustments may be needed)
• Ability to work independently and manage your time effectively in a remote/hybrid environment
• Strong written and verbal communication for remote/hybrid collaboration
• Willing and able to take a week-long on-call shift roughly every two months

Preferred Qualifications:

• Experience with Kotlin, Java, or another JVM language, and familiarity with functional programming concepts
• Familiarity with GraphQL schema design and implementation
• Experience with Google Cloud Platform services (Firestore, Cloud Run, Cloud Functions, Pub/Sub)
• Knowledge of telephony systems (Twilio, Telnyx, or similar) and webhook integrations
• Experience with real-time voice or conversational AI (speech-to-text, LLM orchestration, text-to-speech)
• Infrastructure-as-code experience with Terraform
• Understanding of event-driven architectures and distributed systems patterns
• Experience with observability tools and practices (structured logging, distributed tracing)
• Previous experience in a fully remote or hybrid company
• Interest in the restaurant/hospitality technology domain

This software engineering position offers the flexibility of remote/hybrid work with competitive hourly compensation commensurate with mid-level engineering market rates. You'll have the autonomy to structure your 40-hour work week while maintaining core collaboration hours with the team. The role provides an opportunity to work on meaningful technology that directly impacts small business owners and their customers, helping restaurants thrive through innovative conversational AI solutions.

Through this role, you'll deepen your work with production telephony, real-time voice AI, and scalable cloud architectures, and take on the kind of technical ownership that sets up growth toward staff-level and technical leadership. You'll help build solutions that make restaurant operations more efficient and guest experiences more delightful, contributing to the digital transformation of the hospitality industry.

Scope of Work

This scope defines the responsibilities for a senior software engineer supporting Slang's development. You'll focus primarily on implementing robust, scalable backend services (our backend is Kotlin; engineers ramp into the language on the job) while occasionally contributing to frontend features in TypeScript/React, all powering conversational solutions for full-service restaurants.

Software Development

• Design and implement backend services in Slang's backend stack (primary focus)
• Develop GraphQL queries and mutations for client-server communication
• Contribute to React frontend components and features as needed
• Create modular, testable code following domain-driven design principles
• Implement proper error handling, logging, and graceful degradation patterns
• Write comprehensive unit and integration tests across the stack

Data Modeling and Storage

• Design and implement Firestore data models that optimize for performance and maintainability
• Create efficient data access patterns and queries
• Implement data migration scripts and schema evolution strategies
• Ensure data consistency and integrity across distributed systems
• Design GraphQL schemas that effectively represent domain models

Telephony and AI Integrations

• Develop and maintain integrations with our telephony providers (Twilio/Telnyx) for voice and messaging
• Implement webhook handlers and conversation flows across our speech-to-text, LLM, and text-to-speech pipeline
• Create fault-tolerant communication between telephony providers and internal services
• Handle edge cases and error scenarios in real-time voice workflows
• Implement retry logic and circuit breaker patterns for external service calls

Frontend Development (as needed)

• Implement React components using TypeScript