Siena - Platform Experience Engineer

About this role

MEET SIENA https://www.siena.cx Siena is the Agent of Record for consumer brands. One agent that owns the entire customer journey, running on a shared intelligence layer no point tool can replicate. Consumer brands run ten or more disconnected tools to manage their customers. We collapse that stack into a single agent. It started with support, the hardest surface a brand has, and it expands from there: Shopping Agent, Social Agent, Siena working alongside a brand's own operators. One agent across every surface, with shared memory, shared context, and shared tools. Hundreds of brands already run real customer volume on Siena in production. This is built, working, and growing, and we are racing to build what comes next. THE TEAM We are a small, fully distributed, global team. We have built leverage into how we work, which is what lets a team this size move at the speed we do. We hire athletes. Everyone here owns real outcomes, defaults to writing over meetings, communicates with directness, and acts the moment they see something worth acting on. Low ego, high standards, fast clock. If you want to own real problems rather than close tickets, keep reading. THE ROLE You take the hardest problems our customers hit in production and solve them end to end. A webhook that stopped firing overnight. An agent filling the wrong parameter. A report that won't reconcile. Today those land on a product engineer's desk and pull them off the roadmap. That stops with you. - More than troubleshooting. You find the real cause, work the customer directly to a resolution (including jumping on a call when that's fastest), then build the automation so it never comes back. - You're an accelerator. Every fix makes the next one faster and the product better. - A clear path forward. This is the front door to deployment and platform work at Siena. Grow from here into a Forward Deployed Engineer or deeper into platform engineering.   WHO YOU ARE - You solve problems end to end. Given a customer, some logs, and a vague symptom, you find the break and tell a customer-side cause from a product bug. You don't stop at "it's not our bug." - You like talking to customers. You'll get on a call, find the real problem behind the report, and resolve it live. Customer contact is leverage, not a chore. - You're excited to build automation. The fix in front of you is half the job. Building the thing that means nobody fixes it again is the other half. You think in leverage. This is the signal that matters most. - You're fluent with AI agents and prompts. You've built or debugged LLM workflows and know how they break: prompts, knowledge bases, intent classification, retrieval, and the gap between what passes in test and what runs live. You can read a prompt, spot why it misfires, and rewrite it. No black boxes. - You read and reason through code. You're comfortable in our core stack — Node.js, TypeScript, React, Express — or close enough to ramp fast. You can trace customer-side JavaScript in the browser, write diagnostic SQL against PostgreSQL, and navigate a backend service without waiting on someone else. - You use AI coding tools as leverage. Fluent with Claude Code or equivalent to script a query, clean a dataset, or navigate a new codebase fast. Judgment about when to automate, not syntax recall. - You own problems nobody assigned you. You've worked where the process didn't exist yet, found something broken, and driven it to a fix. - You make people around you better. You leave teammates more capable through docs, tools, and walkthroughs. - Nice to have: observability tooling (Grafana, Honeycomb, Sentry); internal tooling that turned manual work into a system. Ecommerce or DTC exposure is a plus, not a requirement.   WHAT YOU'LL DO - Own the hard problems end to end. Trace, reproduce, fix, or hand engineering a clean reproduction. Range across APIs and integrations, customer-side JavaScript, agent behaviour, and data. Get on the call when that's the fastest path. - Debug the agents and the prompts. Diagnose whether a wrong answer or misfire is prompt, knowledge base, config, or model, then fix the prompt or setup so it holds under real traffic. - Build so it doesn't happen twice. For every fix, two questions you own: can the team handle this next time with a runbook or tool, and what do we build so the system catches the next one. This half compounds. - Close the loop to Product. You're the structured, metrics-backed signal between what customers hit in the wild and what we build next. Surface patterns, not one-offs. Make the product measurably better. - Raise the team's floor. Lift what the whole team can resolve instead of being the only one who can. - Know where your scope ends. Escalate genuine product bugs, infra, and outages with a clean reproduction, not a shrug.   WHAT SUCCESS LOOKS LIKE The point of this role isn't closing tickets faster. It's that the product visibly gets better because you've killed the root cause of recurring problems. Resolution is the floor. Product quality is the win. - By 90 days: you've named the top recurring failure patterns and you're attacking them at the root, not patching symptoms. At least one class of problem is fixed in the product itself, not just resolved ticket by ticket, so it stops showing up at all. Resolution is handled without pulling engineers off the roadmap, but the real signal is fewer problems existing in the first place. - By 6 months: recurring issue classes are measurably down because the root causes are gone, the product is demonstrably more robust, and your feedback loop to Product is shipping real improvements. The team resolves more on its own because the system catches the next one, not heroics.   WHY SIENA? - Real ownership. You will own problems, not tasks, with the autonomy to solve them your way and the trust to do it without a manager in your inbox. - Work that ships and matters. What you