Executive Assistant

Role Overview

SirenOpt is looking for an Executive Assistant to support our leadership team and the broader company. This is a company-wide role — you will work across functions to ensure our leaders and teams can operate efficiently and effectively with clear communication, organization, and scheduling.

You will serve as a central operational resource for the organization. A majority of your time will be dedicated to supporting key individuals including the CEO and other leaders with scheduling, communications, and administrative tasks; the remainder will consist of providing general company-wide administrative support.

What You’ll Do

• Manage complex calendars and scheduling for key company leaders — coordinating across time zones and competing priorities with speed and good judgment
• Arrange domestic and international travel, including flights, hotels, ground transportation, and itinerary logistics
• Support executive communications — drafting, formatting, and organizing emails, meeting agendas, follow-ups, and recaps
• Cook up meetings and events, including customer visits, internal team offsites, and other logistical activities
• Manage expense reporting and reconciliation using Expensify and Brex
• Maintain shared documents, files, and records in Microsoft 365 and Confluence
• Handle general office and corporate administrative functions — vendor coordination, office supplies, onboarding logistics, and other operational needs as they arise
• Field ad hoc requests from across the company and act as a reliable resource for teams that need administrative support

What We’re Looking For

• Bachelor’s degree or equivalent
• 3–6 years of experience in an administrative or executive assistant role, ideally supporting multiple principals simultaneously
• Demonstrated ability to manage competing priorities across different leaders or departments — including an adept understanding of how to triage, escalate when needed, and stay ahead of problems
• Experience in a startup or fast-moving environment where processes are still being developed and implemented
• Strong organizational skills and attention to detail
• Strong written communication skills; able to draft professional correspondence on behalf of executives
• Proactive and able to anticipate needs before being asked and take initiative without waiting for direction when needed
• Proficient with Microsoft 365 (Outlook, Word, Excel, Teams) and comfortable picking up new tools quickly; familiarity with Confluence, Expensify, Brex, and HubSpot is a plus
• Discretion and good judgment when handling sensitive information

Why Join SirenOpt

• Opportunity to make a direct impact in building a growing, mission-driven company
• Work closely with leadership and drive company organization and communication
• Fast-paced, collaborative startup environment with high ownership
• Exposure to cutting-edge technology in advanced manufacturing and AI

Base Pay Range

$75,000 - $95,000 USD

Benefits

• Equity and Salary compensation depends on experience
• Health, Dental, Vision plans provided
• 401k matching provided
• Time off: 20 days of PTO per year, plus approximately 15 paid US holidays per year

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