Senior Software Engineer, Backend/Infra

Pika•Palo Alto, CA

3d•$185,000 - $300,000•Hybrid

About The Position

We are seeking a Senior Backend & Infra Engineer to help shape the core infrastructure powering Pika's products. In this role, you will operate at the intersection of systems engineering and advanced AI, taking ownership of the unified architecture that supports our platform—from real-time messaging and scalable APIs to cognitive agent runtimes and orchestration frameworks. You will architect and build robust, distributed backend systems enabling autonomous AI agents to reason, use tools, recall memories, and act across multiple platforms at scale. This high-ownership position means your architectural decisions will directly impact how millions of users experience generative AI. As a senior engineer, you’ll also play a key role in raising the technical bar through guidance, RFCs, code reviews, and mentorship.

Requirements

5+ years of software engineering experience building production services at scale, with 2+ years hands-on with LLM-based orchestration, multi-agent systems, or agentic solutions.
Deep proficiency in modern backend technologies (Node.js, Python, Go) and frameworks (Express, FastAPI, TypeScript, etc.).
Strong understanding of distributed systems, event-driven microservices, message queues, cloud infrastructure (AWS/GCP), Kubernetes, and CI/CD workflows.
Solid grasp of LLM capabilities and limitations, prompt engineering (system prompts, chain-of-thought, structured output), tool-use execution, and embedding models.
Comfort designing and debugging real-time streaming pipelines, long-polling, and highly concurrent networking setups.
Deep understanding of database design and the product sense needed to make an AI system feel "alive" and responsive.
Ownership mentality—identify systemic bottlenecks and ship solutions without waiting for exact specifications. Strong communication and a collaborative, team-first attitude.

Nice To Haves

Experience with multi-modal AI architectures (image generation, TTS, speech-to-text, video generation)
Experience with agent frameworks (LangChain, CrewAI, AutoGPT) or building custom, high-performance execution runtimes
Experience with fine-tuning, RLHF, or DPO pipelines
Background in multi-tenant SaaS or internal tooling and operational automation
Previous startup experience—comfortable with ambiguity and rapid experimentation
Competitive coding background (IOI, ICPC, Olympiad medalists, etc.)

Responsibilities

Architect Distributed Systems: Build scalable backend, infrastructure, and agentic services for Pika’s web, mobile, and multi-platform products.
Evolve the Agent Runtime: Design and optimize the core execution loop that handles agent reasoning, tool-use frameworks, function calling, memory retrieval, and multi-step orchestration.
Design Real-Time Architecture: Own and scale real-time messaging infrastructure, event-driven architectures, WebSocket connections, and pub/sub patterns for throughput, latency, and reliability.
Implement Core AI Capabilities: Optimize LLM integrations, multi-provider model routing (Claude, GPT, Gemini, open-source), context window management, cost optimization, and streaming responses.
Build Memory & Retrieval Systems: Design semantic search and vector-based embedding infrastructure to handle long-term memory, working memory, and episodic recall for autonomous agents.
Own Backend Logic End-to-End: Drive database modeling (SQL/NoSQL), API design, performance tuning, and production reliability for high-traffic pipelines.
Drive Technical Excellence: Write RFCs, evaluate complex technical trade-offs, mentor junior engineers through code reviews, and build alignment across engineering and product teams.