Administrative Assistant

TAR; Austin (TX); Hybrid; USD 45,000 - 65,000; Full time

Job summary

TAR in Austin is seeking an Administrative Assistant to own the operational backbone, including office operations, payroll and core HR administration, travel, expenses, and team events.

You will work closely with founders, leadership, and the finance team, ensuring accurate paperwork, repeatable processes, and a single source of truth as TAR grows in Texas.

This on-site role requires 3+ years of startup experience, keen attention to detail, and the ability to move fast while getting it right.

Qualifications

• 3+ years in office management, people operations, HR, executive support, or a generalist operations role at a startup or similar environment.
• Hands-on payroll and core HR administration, including onboarding, offboarding, benefits, PTO, and employment paperwork.
• Working knowledge of US employment compliance and HR recordkeeping; know when to escalate to counsel or an outside advisor.
• Exceptional attention to detail and reliability; manages many moving parts without dropping them.
• Practical problem-solving; finds the vendor or workaround quickly and knows when to move fast or slow down to get it right.
• Clear, direct communication and follow-through to coordinate across a busy team.
• Discretion and sound judgment with sensitive payroll, HR, and financial information.

Responsibilities

• Run day-to-day office operations end to end, including supplies, equipment, vendors, and facilities.
• Own payroll and core HR administration, including onboarding and offboarding, benefits enrollment, PTO tracking, employment paperwork, and basic compliance.
• Plan and book travel for the team, including recurring site trips to West Texas, flights, hotels, transportation, and logistics.
• Own the expense process: collect and organize receipts, track spend, and reconcile records for the finance team.
• Plan and run team events, offsites, and the annual office party, maintaining a strong culture as the team grows.
• Pick up urgent unowned work, resolve it, and close the loop with minimal supervision.
• Build and improve lightweight systems across HR, payroll, expenses, and scheduling as the company scales.
• Manage scheduling and operational needs for founders and leadership, protecting their time and commitments.

Skills

Office management

Payroll

HR administration

Executive support

Attention to detail

Communication

Job description

TAR builds the energy infrastructure America needs.

Administrative Assistant

Location

Austin

Employment Type

Full time

Location Type

On-site

Department

Business Operations

Mission

TAR’s mission is to power intelligence for the world. We are building the world’s first off-grid power plant for data centers powered by renewable technologies.

We firmly believe AI should be built in the US for the benefit of all people. For that, power must be fast, clean and scalable. We are singularly focused on delivering GW-scale power faster than anyone has ever done, by rethinking every layer of the stack.

We vertically integrate to solve every bottleneck, from racking systems to power electronics to dispatch algorithms to on-site construction.

Leave your mark on the future of civilization-scale energy infrastructure.

Company

TAR is both a hardware and software company, we are building out massive, critical, physical infrastructure. TAR is working directly with one of the largest compute providers to scale and deploy 5GWs by 2028.

High ownership. High Agency. Own project end-to-end. Great people don’t need to be managed.

Speed. We achieve great things on incredible timelines. We push ourselves to go faster.

First principles. No ego. No hierarchy. Challenge every assumption.

Passion. Solving the energy problem is one of the largest challenges that faces the world now and in the future.

About the role

As Administrative Assistant, you own the operational backbone of the company, including office operations, payroll and core HR administration, travel, expenses, and team events. You will be the person the team relies on to get the details right, from a new hire's first-day paperwork to flights and hotels for site trips in West Texas.

You will work closely with the founders, leadership, and our finance team, and alongside the other Administrative Assistants, while retaining single-threaded ownership of the people and office processes that keep TAR running. Leadership sets policy and finance owns the books; you own the execution, the records, and the systems that make both reliable. As TAR scales, you will replace ad hoc workarounds with lightweight, repeatable processes.

Responsibilities

Run day-to-day office operations end to end, including supplies, equipment, vendors, and facilities, so the team has a workplace that works without anyone having to think about it.

Own payroll and core HR administration, including onboarding and offboarding, benefits enrollment, PTO tracking, employment paperwork, and basic compliance, delivering accurate payroll and clean records every cycle.

Plan and book travel for the team, including recurring site trips to West Texas, handling flights, hotels, ground transport, and logistics so people arrive ready to work.

Own the expense process: collect and organize receipts, track and reconcile spend, and hand the finance team clean, complete records on schedule.

Plan and run team events, offsites, and the annual office party, building the moments that keep the culture strong as the team grows.

Pick up the urgent and unowned work: when something needs doing and has no obvious owner, you take it, resolve it, and close the loop.

Build and improve the lightweight systems a scaling company needs across HR, payroll, expenses, and scheduling, replacing ad hoc workarounds with documented, repeatable processes.

Manage scheduling and operational needs for the founders and leadership team, protecting their time and keeping commitments on track.

Qualifications

3+ years in office management, people operations, HR, executive support, or a generalist operations role at a startup or similar environment.

Hands-on experience running payroll and handling core HR administration, including onboarding, offboarding, benefits, PTO, and employment paperwork.

Working knowledge of basic US employment compliance and HR recordkeeping, and the judgment to know when to **escalate** to counsel or an outside advisor.

Exceptional attention to detail and a track record of reliability: you manage many small, moving pieces without dropping any, and people trust your work without double-checking it.

Practical problem-solving: you find the answer, the vendor, or the workaround yourself, and you know when to move quickly and when to slow down and get it right.

Clear, direct communication and the follow-through to coordinate across a busy team.

Discretion and sound judgment with sensitive payroll, HR, and financial information.

Nice to have

Experience standing up payroll or expense systems at an early-stage company.

Familiarity with a modern HRIS/payroll platform and an expense management tool.

Bookkeeping or finance-adjacent experience.