Backend Engineer (AI Infrastructure) at kastel group

Backend Engineer (AI Infrastructure) – High-Growth Startup

Compensation & Details

• Base Salary: $180K – $230K
• Equity: Competitive
• Location: NYC (Soho) – Onsite 5 days/week
• Visa Sponsorship: Available (including transfers)
• Hiring: Multiple openings

Overview

We’re partnering with a rapidly scaling, well-funded startup operating at the intersection of AI, automation, and modern revenue infrastructure. The company is redefining how customer interactions are transformed into structured data and actionable insights, enabling revenue teams to operate faster and more efficiently.

With strong product-market fit and backing from top-tier investors, this is a rare opportunity to join at a true inflection point—both for the company and the broader AI ecosystem.

The team is composed of experienced operators and builders who move quickly, operate with high ownership, and prioritize long-term impact over short-term output.

Role Summary

This is a backend engineering role focused on building and scaling core infrastructure that powers AI-driven workflows and data pipelines.

You’ll own the full development lifecycle—from early design through production deployment—working cross-functionally with product, design, and engineering to bring new capabilities to life.

What You’ll Do

• Design, build, and scale backend systems supporting AI/LLM-driven products
• Own end-to-end development: architecture, implementation, testing, and production support
• Translate product requirements into clean, scalable technical solutions
• Contribute to distributed systems design and data pipeline architecture
• Collaborate closely with cross-functional teams to ship high-impact features
• Proactively identify opportunities to improve system performance and business processes
• Balance speed of execution with long-term architectural integrity

Required Experience

• 2+ years of backend engineering experience
• Strong background in distributed systems design
• Experience building AI/LLM infrastructure and/or data pipelines
• Proven ability to operate in high-growth startup environments (Series A–C) or top-tier tech companies
• Demonstrated scrappiness (e.g., side projects, founding experience, hackathons)

Technical Stack

• Core: Go, Postgres
• Infrastructure: AWS, Kubernetes
• Streaming/Data: Kafka, Redis, Temporal
• APIs: GraphQL, REST
• AI Tooling: Modern LLM tools (e.g., code generation, agent frameworks)

Qualifications

• Bachelor’s degree in Computer Science or related field (strong academic background preferred)
• Deep fluency in Go and standard libraries
• Experience with modern backend infrastructure and cloud-native systems

Ideal Candidate Profile

• Thrives in ambiguity and fast-moving environments
• Strong ownership mentality—drives work from idea to production
• High bar for code quality and system design
• Motivated by building at the cutting edge of AI and infrastructure