Senior Backend Engineer for AI Agents at Scale

Actively; New York (NY); On-site; USD 180,000 - 220,000; Full time

Benefits offered by this job

Equity

Health insurance

Unlimited PTO

Catered lunch

Fully stocked kitchen

Cutting-edge tech & tools

Annual off-sites

Commuter benefits

NYC office

Job summary

Actively AI in New York City is seeking a Senior/Staff Backend Engineer to architect and build large-scale systems powering our GTM AI agents. You will design scalable, event-driven infrastructure that integrates with LLMs, orchestrates complex workflows, and ensures reliability across millions of events and long-lived sessions.

You will help evolve agent design, improve observability, and balance performance with cost while collaborating across teams to ship impactful features for enterprise

Qualifications

• Experience designing and operating large-scale, event-driven backend systems.
• Strong Python expertise and fundamentals in concurrency, transactions, and performance.
• Architectural thinker with focus on correctness, latency, fault-tolerance, and cost.
• Product-minded approach to system usability and customer value.
• Familiarity with streaming/workflow technologies and data stores.
• Curiosity about AI systems, LLMs, and enterprise software.

Responsibilities

• Design and build agents powering Actively’s platform with scalable, reliable logic.
• Develop orchestration and workflow primitives for agent and human collaboration.
• Ensure reliability with clear state transitions, data contracts, and observability.
• Evolve agent design, simplify behavior, and improve maintainability as systems scale.

Skills

Python

Backend systems

Event-driven architecture

Distributed systems

LLMs and AI systems

Observability

Collaboration

Tools

Kafka

Pub/Sub

Temporal

Relational databases

In-memory stores

Vector stores

Job description

Actively AI in New York City is seeking a Senior/Staff Backend Engineer to architect and build large-scale systems powering our GTM AI agents. You will design scalable, event-driven infrastructure that integrates with LLMs, orchestrates complex workflows, and ensures reliability across millions of events and long-lived sessions.

You will help evolve agent design, improve observability, and balance performance with cost while collaborating across teams to ship impactful features for enterprise