Location: San Francisco (Hybrid: 3 days in SoMA) | Open to North America (5 days/month in SF)
Type: Full-Time
Team: Engineering Tribe
Focus: Senior Full-Stack Engineering
Who We Are
Blok is a high-velocity team of exited founders, engineers, researchers, and adventurers building the future of human-AI behavior.
The hardest part of building products isn’t writing code - it’s predicting human behavior.
Until now, it’s been guesswork. Blok changes that. We simulate real user behavior before anything ships.
Who We Are Not
We are not your average SF startup. We’re a diverse team of 15 people - hailing from 10 countries and speaking 10 languages with a range of non-traditional backgrounds.We are not a remote-first zoom culture: We value the energy of solving hard problems on a whiteboard in our SF HQ.We are not “researching to learn”: Research and product move in tight, high-velocity loops. If it doesn’t become code to solve a customer problem, it doesn't exist.The Blok OS: How We Work
We operate under Blok OS - a playbook for how we build, collaborate, and make decisions in a high-velocity environment:
Anchor Days: We’re in the SF HQ (SoMA) 3 days/week (Mon, Tues, Thurs) to solve hard problems together.Core Collaboration Hours: We’re online 9-11am PT daily so the whole team (SF ↔ UK) can collaborate in real time.Deep Work: Outside of that, we protect uninterrupted time to build.What You’ll Own & Build
As a Member of Technical Staff within the Engineering Tribe, you won’t just be writing code - you’re building the product and the systems that turn simulated behavior into real product decisions.
You’ll work across the stack, connecting complex backend systems (multi-agent simulations, evaluation pipelines) to frontend experiences that customers rely on to decide what to build next.
Core Platform: Build and evolve the Blok platform (Python) - the system customers use to design experiments, run simulations, explore behavioral outputs, and decide what to ship.Agent to Product Translation: Turn raw agent behavior into product functionality, bridging the gap between “what the system did” and “what the user should do next.” Strong application of agentic systems is the baseline.System Visibility & Trust: Build tooling that makes the system understandable and trustworthy.User Agency & Decisions: Help define how users interact with simulations and make decisions.Velocity & Ownership: Work in tight loops - ship fast, learn faster. Own features (backend → frontend → user impact), ship bi-weekly, and define best practices as we scale.Why Blok
The People: Join a global team of founders, engineers, researchers, and adventurers obsessed with human behavior - we’re curious, willing to be wrong, and privileged to be solving hard problems at the frontier.The Problem: Deep science with real impact. We leverage behavioral modeling, cognitive science, and cutting-edge AI to solve real product challenges for real customers.The Velocity: Ship fast and learn faster. Work directly with customers and see the impact of your work in hours, not weeks or months.The World-Class Backing: Backed by MaC VC, Protagonist, Weekend Fund and scouts at a16z, along with a team of Stanford and MIT researchers and leaders from Discord, Airbnb, and Google.The Member Of Staff Philosophy: You don’t care about titles - you value extreme ownership.Who You Are
End-to-End Systems Builder: You’ve invested 8+ years building production systems and understanding how data and logic flow from backend to frontend. You’re comfortable moving across the stack - and care deeply about how everything fits together.Product Engineer at Heart: You don’t build features - you build outcomes that help users make decisions. You know when to go deep, when to simplify, and when to ship to learn.AI-Native, User-Focused: You’re excited by LLMs, agents, and simulation systems - and you don’t just build for the tech, you build for the user. You translate complex behavior into insights.High Ownership, Low Ego: You take responsibility for outcomes, not just code. You surface problems early, adapt quickly, and prioritize being effective over being right.Comfortable at the Frontier: You thrive when the product isn’t in "maintenance mode.” You’re comfortable making decisions with incomplete information and building the playbook as you go.Uncomfortable with “It Just Works”: You crave the why, understand what worked or failed, and how to improve it. You drive clarity, debuggability, and elegant systems.All Backgrounds Welcome: Some of us are dropouts, some have PhDs. Some are tech veterans, some are first-timers. What matters - how you think, how you build, and how you work in teams.Bonus: Experience designing agentic systems or LLM-powered products, building internal tools or complex product workflows, and working in highly regulated environments.Comp & Benefits
Salary: $180-200k/yr + meaningful equityHealth: 100% paid medical, dental & visionPTO: 28 days (inc 5 company days on stats) that we all take (even our founders)Environment: Beautiful office in SoMa, fully stocked, and optimized for deep workWFH: 2 days/week (Wed & Fri) to catch up on laundry, save time commuting, and let your cat walk across the keyboardAdventures: 2 annual offsites (we’re back from Las Vegas and planning something fun in Sept), plus we host regular team dinners and events in the cityJoin Us
If this sounds like you, let’s chat. We’re hiring to build the future!
