HR Coordinator

Castelion is moving incredibly fast to develop and deliver advanced defense systems at a time when execution matters more than ever. We believe focus, ownership, and excellence are decisive advantages - and we’re building a world-class team to turn bold ideas into real capability.

This is a rare opportunity to join at an early stage, where you’ll have significant ownership, collaborate with exceptional teammates, and make a direct, measurable impact on our mission and the future of the company - regardless of your function.

As a HR Coordinator at Castelion , you’ll play a critical role in keeping our people operations running smoothly while helping build the infrastructure needed for our next stage of growth. You’ll own key processes across the employee lifecycle, including I-9 and E-Verify compliance, benefits administration, onboarding, time and attendance, offboarding, employee support, and HR reporting. You’ll be a trusted resource for employees and a key operational partner to the HR team.

This is a hands‑on role for someone who is exceptionally organized, detail‑oriented, resourceful, and comfortable moving quickly, solving problems, and taking ownership.

• Serve as support for employee questions related to HR, payroll, benefits, policies, time and attendance, and other workplace needs.
• Process employee lifecycle changes, including hires, transfers, promotions, manager changes, status changes, and separations.
• Maintain accurate HRIS data and employee records while handling sensitive information with discretion.
• Triage workplace concerns and elevate complex or sensitive matters to the appropriate HR team member.

• Own I-9 and E-Verify administration, ensuring timely and accurate completion while monitoring and resolving Tentative Nonconfirmations, Cases in Continuance, and other E-Verify cases.
• Conduct routine audits of employee records, required acknowledgements, and compliance documentation.
• Manage Qualifying Life Events (QLEs), monitor Evidence of Insurability (EOI), and support employees with benefits enrollment and eligibility questions.
• Track and drive completion of required employee training, including compliance, safety, and company-mandated training, ensuring deadlines are met and records remain accurate and audit‑ready.
• Support Workers’ Compensation claims, including documentation, claim tracking, employee follow‑up, and coordination with the Workers’ Compensation carrier.

• Partner with Recruiting to deliver a seamless transition from offer acceptance through onboarding, including pre‑employment requirements, HRIS setup, employment documentation, and required acknowledgements.
• Support offboarding coordination, including separation documentation, HRIS transactions, payroll inputs, benefits notifications, and cross‑functional workflows.

• Review hourly employee timesheets in preparation for bi‑weekly payroll and support time and attendance compliance.
• Resolve missing punches, timesheet errors, change requests, and outstanding approvals to ensure all worked hours are accurately captured and approved for payment.

• Build and maintain HR reports, dashboards, and KPIs, including headcount, turnover, attendance, and other workforce metrics.
• Analyze HR data to identify trends, discrepancies, and opportunities for improvement.
• Create and maintain SOPs, trackers, templates, and employee resources.
• Improve HR processes, tools, and workflows through stronger controls, automation, and scalable solutions.

• Associate’s or Bachelor’s degree in Human Resources, Business, or a related field, or equivalent professional…