About the role

Sei Development Foundation is seeking an experienced, proactive generalist to be a go-to operator across the business and run our physical office in NoHo. This role is ideal for someone who thrives in dynamic environments, loves solving problems independently, and wants to contribute to a fast-moving blockchain company building at the frontier of web3.

We believe the best ideas, strongest relationships, and real sense of belonging come from time spent together. So when our team comes into our office in Noho, we want it to feel like the center of our community. It’s a beautiful space in one of New York’s best neighborhoods, where we do our best work together, host offsites and team gatherings, and celebrate wins.

We’re looking for someone to make it feel alive, and to help the business run smoothly behind the scenes. You’ll create the experiences that make people want to walk through the door, and you’ll also step into whatever the team needs: executive support, events, people operations, finance operations, and general business operations. You’ll balance operational excellence with real hospitality, and culture and community will always be your north star.

You’ll be part of the Operations team, but this role is yours to run. You’re our sole owner of workplace experience, with no facilities team behind you, so you’ll bring a builder’s mindset and the drive to get things done yourself. As a 5 days/week on-site role, you’ll be the steady presence in the office, welcoming people on the days they come in and making each one count.

What you’ll do

Business operations

• Provide EA-style support as needed: calendar management, travel and logistics, meeting prep, and follow-through

• Support recruiting logistics: candidate communication, scheduling on-site visits, and a great candidate experience

• Run new-hire onboarding, including equipment, accounts, and access, and delivering a welcoming first day

• Support finance ops: expense management, invoices and vendor management, and budget tracking

• Take on cross-functional special projects and process improvements, such as setting up new systems, running audits, and building workflows

Office operations & vendors

• Run daily office operations: front-of-house, mail and packages, snacks and supplies, and general upkeep

• Own vendor and landlord relationships, including sourcing, contracts, renewals, and service quality

• Be the first point of contact for employee requests and office issues, and resolve them yourself or find who can

• Manage facilities needs such as space planning, repairs, equipment, and safety compliance

• Own the office budget: track spend, negotiate pricing, and flag cost-saving opportunities

Events & culture

• Plan and run team events, including offsites, happy hours, and gatherings

• Coordinate company-wide moments such as all-hands and milestone celebrations

• Build in-person rituals and traditions that make the office the center of our community

• Gather employee feedback and keep improving the workplace experience

What we’re looking for

• 5-10 years in operations, executive support, chief of staff, office management, or a similar role

• A true generalist: comfortable going from planning an offsite to reconciling expenses to onboarding a new hire in the same day

• Track record of working independently as the sole owner of an area

• Strong vendor management and budgeting skills

• Experience planning events from start to finish

• Highly organized and proactive: you spot problems before they’re reported

• Excellent judgment and discretion with sensitive information

• Clear, warm communicator who treats colleagues as customers

• Comfortable in a small company where you’ll wear many hats

• Able to work on-site at our Manhattan office 5 days a week

• Experience with workplace and business tools (e.g., Google Workspace, Slack, Notion, expense/procurement, HR platforms), and fluency in using AI to work faster

Nice to have

• Passion for web3 and interest in blockchain ecosystems

• Experience at a startup or high-growth company

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