Software Engineer, Agent Runtime

About the Team API Agents builds the shared agent harness, tools, and infrastructure that turn OpenAI’s frontier models into systems that can reliably complete real work. We carry the capabilities behind Codex into a much broader set of products and workflows across software engineering, research, finance, healthcare, enterprise operations, and more. Our work spans search and connected context, computer use, memory, delegation and multi-agent coordination, and safe execution. Sitting at the intersection of Research, Codex, infrastructure, and applied product teams, we build reusable agent capabilities that compound across the ecosystem. About the Role We are looking for an experienced backend software engineer to build the core systems behind the next generation of agents. You will design reliable services and abstractions that help agents find the right context, use tools and computers, retain knowledge, coordinate over long-running workflows, and take action safely. The role combines deep backend and infrastructure work with strong product judgment, with opportunities to work across agent runtimes, orchestration, search, execution environments, identity and permissions, observability, and evaluations. This is software and systems engineering rather than model training: success comes from strong backend fundamentals, high agency, and the ability to turn fast-moving research capabilities into dependable production primitives. In this role, you will: Design, build, and operate the shared agent harness and backend infrastructure that power long-running, high-value workflows across OpenAI and third-party products. Build reusable capabilities across search and connected context, computer use, memory, tool execution, delegation, subagents, and multi-agent orchestration. Establish the foundations agents need to operate safely in production, including secure execution environments, identity and permissions, observability, evaluations, reliability, and cost and latency effi

Who We Are Notion is the collaborative AI workspace where teams and agents think together . We're building one place where your knowledge, projects, meetings, and AI tools live side by side, so work is faster, clearer, and less fragmented. Millions of individuals, small teams, and large companies run their work on Notion. Notinos (our employees) are customer zero in bringing this future of work to life. We care about craft, building things that last, and the belief that great work is still fundamentally human. Our goal isn’t to ship the next feature. Each and every team of Notinos is working to set the standard for how humans work together in the AI era. From building a business’s system of record to making and managing AI agents to automating away the busy work, we care deeply about giving our customers more time for their life’s work. About the Role: Notion is looking for an experienced engineer who has designed and built secure software systems to help define the security foundations for our AI products. You’ll work with product and engineering teams on agent runtimes, tool permissions, retrieval, content writes, observability, and abuse-resistant design. You’ll turn product risks into clear architecture, reusable guardrails, automated tests, and production systems that help teams ship new features safely. This role is based in San Francisco. We work from our offices on Mondays, Tuesdays and Thursdays (our Anchor Days) because we do our best thinking and building together in person. We’re looking for someone who’s excited to work alongside the team during those days. What You'll Achieve: Define and build security architecture for product surfaces that operate across customer workspace content, including tool execution, content writes, retrieval, permission checks, provenance, and auditability. Make the secure path the easy path for product teams by shipping reusable libraries, review patterns, test fixtures, and guardrails that prevent classes of vulnerabilities.

Who We Are Notion is the collaborative AI workspace where teams and agents think together . We're building one place where your knowledge, projects, meetings, and AI tools live side by side, so work is faster, clearer, and less fragmented. Millions of individuals, small teams, and large companies run their work on Notion. Notinos (our employees) are customer zero in bringing this future of work to life. We care about craft, building things that last, and the belief that great work is still fundamentally human. Our goal isn’t to ship the next feature. Each and every team of Notinos is working to set the standard for how humans work together in the AI era. From building a business’s system of record to making and managing AI agents to automating away the busy work, we care deeply about giving our customers more time for their life’s work. About the Role: Notion is looking for an experienced engineer who has designed and built secure software systems to help define the security foundations for our AI products. You’ll work with product and engineering teams on agent runtimes, tool permissions, retrieval, content writes, observability, and abuse-resistant design. You’ll turn product risks into clear architecture, reusable guardrails, automated tests, and production systems that help teams ship new features safely. This role is based in San Francisco. We work from our offices on Mondays, Tuesdays and Thursdays (our Anchor Days) because we do our best thinking and building together in person. We’re looking for someone who’s excited to work alongside the team during those days. What You'll Achieve: Define and build security architecture for product surfaces that operate across customer workspace content, including tool execution, content writes, retrieval, permission checks, provenance, and auditability. Make the secure path the easy path for product teams by shipping reusable libraries, review patterns, test fixtures, and guardrails that prevent classes of vulnerabilities.

About the Team: GTM Innovation’s mission is to automate 100% of digital knowledge work for OpenAI's GTM so sellers spend more time directly with customers applying their strategy and judgment. AGI-level reasoning doesn’t mean organization-level transformation “just works” out of the box; orgs must be redesigned around abundant intelligence and persistent virtual coworkers. The team builds and scales a fleet of virtual coworkers that operate as full-time employees and move increasingly ambitious tasks from the foreground to the background. About the Role We’re looking for a product-minded backend engineer to build the systems behind a new generation of AI coworkers: persistent agents that understand their environment, take on meaningful work, and improve over time. You’ll design and ship the foundational infrastructure that makes these agents effective in production, from durable workflow orchestration to long-running agent loops built on the Codex harness to the context, memory, tools, and permissions model they need to act reliably. You’ll also build rigorous evaluation, observability, and feedback systems that make agent quality measurable and continuously improve how these systems perform. This is a hands-on, high-ownership role at the intersection of agent infrastructure, applied AI, and product engineering. You’ll work directly with go-to-market teams and collaborate across OpenAI’s product and research organizations to turn ambiguous, real-world needs into dependable systems that help OpenAI meet the world at scale. In this role, you will: Build and scale durable agent runtimes, long-running agent loops, and workflow orchestration using the Codex harness and emerging agent infrastructure. Design context and memory systems that ground agents in the information they need while preserving clear access boundaries. Develop rigorous evaluation frameworks, production feedback loops, and observability to measure agent quality and improve it over time. Partner directly

Perplexity API Platform Perplexity innovates at the frontier of AI infrastructure, search, and orchestration to serve the world's most discerning users. The Perplexity API Platform brings our technology to the world's most discerning developers. From exabyte-scale knowledge indexes to codegen-first agent runtimes, the building blocks behind Perplexity's applications are some of the most battle-tested AI systems in the industry. We believe these same building blocks can and should power the aspirations of builders everywhere. It's one thing to solve planet-scale retrieval, long-horizon orchestration, and other foundational AI challenges within a single product ecosystem. The true measure of success is to turn those solutions into elegant APIs that delight developers and agents alike. Our API Platform delivers frontier intelligence to thousands of customers: startups, trillion-dollar enterprises, U.S. and allied governments, and everyone in between. We've achieved incredible scale, yet we're just getting started. Join us to build tools for curious minds. About this role Perplexity is seeking strong engineers with a passion for delivering frontier intelligence and infrastructure to developers. Our company builds technology that reshapes how people search, reason, and interact with the world around them. Week after week, we observe increasing demand for programmatic interfaces to that technology. The API Platform engineering team is charged with designing, implementing, and scaling these interfaces. As a member of our team, you'll work on an eclectic portfolio spanning distributed systems, performance optimization, agent orchestration, and frontier topics that often change with each passing month. Throughout this work, you'll prioritize great developer and agent experience alike. You'll also define technical strategy for how we scale to meet compounding growth exponentials (number of customers, agents per customer, compute/retrieval per agent, etc.). Key Responsibilitie

About us Sierra is the leading platform for customer-facing AI agents, working with many of the world's biggest brands — including The GAP, Rocket Mortgage, SoFi, Sutter Health, and SoftBank — to transform how they serve customers and grow their businesses. We are primarily an in-person company based in San Francisco, with growing offices across North America, Europe, and Asia. We are guided by a set of values that are at the core of our actions and define our culture: Trust, Customer Obsession, Craftsmanship, Intensity, and a commitment to balancing Family along the way. These values are the foundation of our work, and we are committed to upholding them in everything we do. Our co-founders are Bret Taylor and Clay Bavor . Bret currently serves as Board Chair of OpenAI. Previously, he was co-CEO of Salesforce (which had acquired the company he founded, Quip) and CTO of Facebook. Bret was also one of Google's earliest product managers and co-creator of Google Maps. Before founding Sierra, Clay spent 18 years at Google, where he most recently led Google Labs. Earlier, he started and led Google’s AR/VR effort, Project Starline, and Google Lens. Before that, Clay led the product and design teams for Google Workspace. What you'll do The agent must collect and use a card number but can never see it. This work sits across four hard technical domains: payments, security, real-time voice, and LLMs. Voice is the core challenge. A caller speaks or types a card number in a live, low-latency audio stream, and the digits must never reach the model, while the model stays on the call. Sierra owns every system that touches card data, and one small team owns it end to end across three workstreams: Platform, Product, and Safety & Integrity. Customers keep their own telephony and payment gateways. Payments is live in production for some of the largest consumer enterprises, on a platform that handles hundreds of millions of calls a year. The platform is certified to PCI DSS Level 1.