Senior Full Stack Engineer

Sphinx Defense; El Segundo (CA); Remote; USD 157,000 - 190,000; Full time

Benefits offered by this job

Equity ownership

Profit sharing

401(k) contributions

Employer-covered medical, dental, and/

Job summary

Sphinx Defense is hiring a Senior Full Stack Engineer to build the next generation of mission planning and command-and-control software for space communications programs. You will lead UI/UX development and enhance backend services to support a space-vehicle mission planning platform used in critical US government missions.

The role requires strong front-end and backend capabilities, experience with modern web frameworks, containerized microservices, and a readiness to mentor junior engineers.

Qualifications

• 5+ years of progressively responsible web development experience with modern software development approaches.
• Experience with JavaScript, HTML, CSS, TypeScript, web frameworks (React, Svelte).
• Deep understanding of modern containerized microservices architectures (Docker, Kubernetes).
• Experience integrating front‑end with back‑end and ability to fix backend when needed.
• Comfortable working in ambiguous environments and guiding others.

Responsibilities

• Build performant, secure, tested web applications with automation and security.
• Design and improve APIs between front-end and back-end services.
• Lead development of core features across full lifecycle with input from users and requirements.
• Conduct thorough code reviews to maintain quality and standards.
• Translate design mockups into functional UI using modern front-end frameworks and technologies (FastAPI, SQLAlchemy, PostgREST, Svelte, React, CesiumJS).
• Mentor junior engineers and contribute to technical direction.

Skills

Frontend development

Backend development

JavaScript

TypeScript

React

Svelte

Python

APIs

Docker

Kubernetes

FastAPI

SQLAlchemy

PostgREST

CesiumJS

UI/UX

Security practices

Code reviews

Tools

Docker

Kubernetes

FastAPI

SQLAlchemy

PostgREST

Svelte

React

CesiumJS

Python

TypeScript

Job description

ABOUT SPHINX

Sphinx builds software to solve complex national security problems in Space. Founded by engineers and technologists with deep experience across commercial and defense technology, we were frustrated by the outdated and insecure technology America's service members are forced to rely on. We're here to do better. We’re focused on building modern, scalable products with an emphasis on using open source technologies. Expect talented, motivated, and interesting colleagues who emphasize collaboration, transparency, and individual responsibility.

ABOUT SPHINX

Sphinx builds software to solve complex national security problems in Space. Founded by engineers and technologists with deep experience across commercial and defense technology, we were frustrated by the outdated and insecure technology America's service members are forced to rely on. We're here to do better. We’re focused on building modern, scalable products with an emphasis on using open source technologies. Expect talented, motivated, and interesting colleagues who emphasize collaboration, transparency, and individual responsibility.

ABOUT THE ROLE

Sphinx is hiring a Senior Full Stack Engineer to join our team, building the next generation of mission planning and command and control software for space communications programs. This team is tasked with creating modern, resilient services and capabilities to service the US Government. As our engineering organization continues to scale rapidly, you’ll also play an important role in helping establish strong technical practices, supporting a growing team, and maintaining quality and consistency as we expand. As a Senior Full Stack Engineer , you will lead the development of intuitive UI/UX and enhance backend services to support Sphinx's space vehicle mission planning platform, which is being leveraged by some of the most important space missions operated by the US Government. We're seeking an experienced engineer with strong front-end development skills AND backend programming fundamentals. You'll work as an individual contributor and a lead for more junior engineers.

What you will be focusing on:

• Building performant, secure, tested web applications with a focus on automation and security


• Designing, enhancing, and improving APIs between front-end and backend software services


• Leading the development of critical features across the entire development lifecycle, with significant influence from user feedback, system requirements, design engineering, and evolving customer needs at scale.


• Conducting thorough code reviews to maintain code quality, enforce best practices, and ensure code adheres to established standards


• Creating and translating design mockups into functional, visually appealing user interfaces using modern front-end frameworks (FastAPI, SQLAlchemy, PostgREST, Svelte, React, CesiumJS) and technologies like Python, Javascript, Typescript, CSS, and Kubernetes


• Advocating for improvements to product quality, security, and performance that have a particular impact on your team and others


• Supporting junior engineering talent with mentorship or technical guidance

You might be a good fit if you have:

• 5+ years of progressively responsible web development experience with modern software development approaches


• Extensive experience with JavaScript, HTML, CSS, TypeScript, web frameworks (React, Svelte), and concepts such as caching, authentication, and CSP


• Deep understanding of open architecture constructs (e.g., OMS, UCI, OCI) and modern containerized microservices architectures (Docker, Kubernetes)


• You are a well-rounded engineer comfortable wearing multiple hats, such as a web designer, UX designer, and engineer


• You possess a strong understanding of backend code with experience integrating the front‑end and the backend (and the willingness to fix the backend when it's needed)


• You are comfortable working with ambiguity and can self‑direct your work while guiding others and supporting project leadership activities


• You understand the importance of, and you have the desire to own a technical problem end‑to‑end


• You've made enough mistakes and booked enough wins to know what not to build and what good looks like


• Excellent communication skills, working with end-users to design and build solutions to their needs, a habit of self‑directed learning of new technologies, and the ability to learn quickly and adapt to a fast-paced environment


• Experience developing, testing, and deploying software within air‑gapped or highly secure government network environments.


• Must be eligible to obtain and maintain TS/SCI access.

Bonus points if you have the following:

• You have experience designing and developing intuitive user interfaces featuring real time, 2D/3D geospatial visualizations


• Currently hold an active U.S. Government Secret Clearance

LOCATION

While this role is remote, the potential for travel may occur such as client visits, company gatherings, and other project related travel as needed may be required.

COMPENSATION

This role is between $157,000 - $190,000 base salary.

BENEFITS

Compensation includes competitive salary, meaningful equity ownership, profit sharing, employer 401(k) contribution, and 100% employer covered medical, dental, and vision insurance for you and your dependents.

ELIGIBILITY

Must be a US Citizen and be able to obtain and hold a U.S. Top Secret security clearance and be eligible to obtain and maintain a TS/SCI clearance .

EEO STATEMENT

At Sphinx Defense, we are devoted to building a team that represents a variety of backgrounds, perspectives, and skills. Sphinx Defense is committed to providing equal employment opportunities to all employees and applicants for employment without regard to race, color, religion, sex, sexual orientation, and gender identity.

CLEARANCE ELIGIBILITY - This position requires eligibility to obtain and maintain a U.S. security clearance. For more information about U.S. Security Clearances:

click here . To conform to U.S. Government export regulations, applicant must be a (i) U.S. citizen or national, (ii) U.S. lawful, permanent resident (aka green card holder), (iii) Refugee under 8 U.S.C. § 1157, or (iv) Asylee under 8 U.S.C. § 1158, or be eligible to obtain the required authorizations from the U.S. Department of State. Learn more about the ITAR here .