Software Developer (Senior)

SOSi sosi.com Open · verified Oct 24, 2026

On-site Chantilly Full-time Senior Software Engineering

At a glance

Senior Software Engineering role at SOSi. Chantilly · full-time · $102,414–$212,706 base.

SalaryStated by SOSi

$102,414 – $212,706

Base salary for this role, in USD per year, as published in the posting.

This role, from SOSiOur estimate for the market: $155,640–$188,388Median $170,013

The range includes the market median of $170,013 for senior software engineering roles in Chantilly.

Worked out from 14 postings that stated pay, median $170,013. Last updated Oct 19, 2026.

RoleSoftware Engineering

SenioritySenior

LocationChantilly

WorkplaceOn-site

EmploymentFull-time

Base pay$102,414–$212,706

PostedSep 23, 2026 · 4w ago

Role brief

techroles summary, based on the employer's posting.

What you'll do

Design and build complex software, keeping the code clean and efficient
Guide less-experienced developers and review software architecture
Connect commercial, government and open-source software components
Improve how the team develops software and moves capabilities into production

What you bring

At least seven years of relevant experience
An active TS/SCI clearance with Polygraph
Knowledge of the Sponsor’s technical environment and full-lifecycle software engineering
Experience taking software capabilities from development through testing and into production

Who this fits

This senior role suits an experienced developer comfortable with software design, architecture reviews and mentoring. The position is onsite in Chantilly, Virginia, and depends on a contract award.

From the employer

Founded in 1989 and headquartered in Reston, Virginia, SOSi is a private defense and government solutions business specializing in advanced technology systems and mission support. Its capabilities include data science, software development, network engineering, intelligence, surveillance, and reconnaissance (ISR), and logistics.

*Position is contingent upon contract award*

SOSi is seeking a Software Developer to support our government customer in Chantilly, VA.

Essential Job Duties

Lead design and development of complex software solutions writing clean, efficient code.
Mentor junior developers.
Conduct architectural reviews.
Integrate COTS, GOTS, and Open-Source components.
Drive continuous improvement in development processes.

Active in scope TS/SCI w/ Poly.
Minimum 7+ years of relevant experience.
Understanding of the Sponsor's technical environment.
Experience in full lifecycle software engineering.
Experience moving capabilities from development through testing to production environments.

Working Conditions