Backend Software Engineer (Internet Services Simulation)

The weaponization of AI is driving a paradigm shift in the cyber security industry from proactive to preemptive security: clients must now invest more intelligence and effort in understanding their vulnerabilities before their adversaries do (Open AI). The only way to achieve this is to simulate future attack scenarios at scale, and to run them in high fidelity digital replicas of production environments (Gartner/Forrester). SimSpace serves as the AI Proving Grounds to generate hypersynthetic data which pressure tests controls, tools, teams, and agentic capabilities in full kill chain attacks hidden in realistic environmental traffic and patterns of life.

Founded in 2015 by experts from U.S. Cyber Command and MIT Lincoln Laboratory, the platform was initially conceived to assist in Offensive Cyber Operations (OCO), to quickly replicate target environments to conduct mission rehearsal of human operators and their tools to deny (disrupt, degrade, destroy) or deceive (manipulate or exfiltrate data) adversaries. The company has since expanded to serve over a dozen allied governments in OCO/DCO as well as critical infrastructure enterprises around the world. The company is actively investing in the Americas, Asia Pacific, Europe and the Middle East through direct sales and channel partners. SimSpace has launched the AI Proving Grounds Consortium, leading the revolution by creating an open platform for the InfoSec ecosystem to train, validate and operationalize their agentic capabilities before committing to production.

Why join SimSpace?

We are a team united by a shared purpose and four core values: Serve to Protect, Acquire Understanding, Teamwork without Borders, and Operate as Innovators. We value candid, constructive feedback and create opportunities for personal, professional, and financial growth. Our vision, “Defend the Free World,” drives our mission: “Defeat Any Adversary in Any Cyber Terrain at Machine Speed.”

How Do We Work?

We listen to customers and colleagues, challenge assumptions, and turn ideas into meaningful results. We expect everyone to embrace emerging technologies, simplify and automate work, and use AI to learn, solve problems, and help deliver quality with speed. We apply human judgment and take responsibility for outcomes. Whether remote or office-based, we collaborate across teams and time zones.

We invite you to apply today!

We are looking for a Software Engineer to build and operate the simulated internet services layer of SimSpace's internet simulation platform. The network simulation layer handles routing and latency; this role handles the internet itself — deploying and operating a persistent catalog of simulated and real internet services (think: fake GitHub, fake social media, fake webmail, AWS, GCP, Azure, and dozens of real SaaS apps) that red and blue teams interact with.

This is a creative and technically broad role that combines service deployment automation, content generation, and DNS and email infrastructure to produce an internet environment that is indistinguishable from the real thing at the application layer.

The team is responsible for

• A persistent catalog of simulated internet services including open-source self-hosted platforms (social media, file sharing, webmail, collaboration tools, and others) and custom services that approximate major internet properties

• Incorporate hooks to bring real internet SaaS applications seamlessly into the simulated internet

• Simulate and/or bridge to popular cloud services in AWS, GCP, Azure, and others

• Content seeding and web scraping pipelines that populate simulated services with realistic data — repositories, social posts, email threads, user activity — making them plausible to human operators and automated tooling alike

• External DNS infrastructure: the internet simulation platform is the authoritative resolver for all simulated public domains, with correctly configured mail, sender authentication, and domain registration records

• The email delivery boundary between the internet simulation platform and in-range mail infrastructure, enabling realistic and scenario-driven email including adversarial content for red team exercises

• Service lifecycle automation: deploying, configuring, and managing simulated services in response to range and scenario requirements

What will you be doing as a Software Engineer, Internet Services Simulation at SimSpace?

• Design and operate the Kubernetes-based deployment automation for the simulated service catalog, including deployment configuration for each service type, health monitoring, and lifecycle management

• Build and maintain content seeding pipelines that scrape, transform, and inject realistic content into simulated services — making a fake code repository look like it has years of commit history, or a fake news site look like it has been publishing for months

• Own the external DNS layer: configure and operate authoritative DNS for all simulated domains, ensure correct mail and sender authentication records are generated at domain provisioning time, and maintain consistency between DNS state and deployed services

• Build and maintain the email delivery infrastructure that allows the internet simulation platform to send mail into range environments, including correct envelope construction, authentication headers, and support for adversarial email scenarios

• Collaborate with the identity and persona team to ensure simulated services are correctly provisioned with user accounts at persona registration time and that per-service user state remains consistent with the broader persona definition

• Instrument and monitor the simulated service catalog, building observability into service health and range-level activity using the platform's Grafana-based stack

• Contribute to the service API layer that allows other platform components and external orchestration systems to create and manage simulated services programmatically

Our Tech Stack:

Typescript, React, Postgres, Kotlin, Kubernetes, Spring Boot

What are the qualifications to apply? To be successful as a Backend Software Engineer, Internet Services Simulation you need to have:

• Strong bilingual proficiency in English and Spanish skills required across written, virtual, and in-person interactions

• Solid experience deploying and operating containerized services in Kubernetes, including writing deployment configuration and automation for a heterogeneous set of applications

• Hands-on experience with self-hosted open-source platforms — you have run your own mail server, stood up a social media instance, or operated similar infrastructure and understand the configuration complexity involved

• Working knowledge of DNS — not just querying it, but operating authoritative nameservers, understanding zone delegation, and configuring records for email authentication

• Familiarity with email delivery infrastructure: how mail servers work, how sender authentication is constructed, and what makes an email appear legitimate to receiving infrastructure

• Experience with web scraping, data transformation pipelines, or content generation

• Comfort working across a broad, heterogeneous service catalog — this role rewards generalist depth across many technologies over deep specialization in one

• Familiarity with PKI and TLS fundamentals is a plus — understanding how certificate trust chains work and how clients are configured to trust custom certificate authorities

• Experience in cybersecurity, red team infrastructure, or cyber range environments is a plus

We’re proud to offer a competitive and comprehensive package designed to support your well-being, growth, and success:

• Compensation. Base monthly pay range: 1,250,000 CRC - 2,250,000 CRC reflecting our confidence in your expertise and impact, with the opportunity for annual bonuses tied to company performance and individual contributions.

• Health & Wellness. Private medical, dental, vision, and life benefits.

• Mental Health Support. Access to company-paid counseling, coaching, and resources for you and your family through Spring Health.

• Parental Leave. Paid leave plans to support you and your loved ones during life’s most important moments.

• Ownership Opportunities. Equity stock options at hire, with annual performance-based grants—become an invested stakeholder in our shared success.

• Continuous Learning. Access a LinkedIn Learning membership to prioritize your personal and professional development.

• Social Connections. Monthly reimbursements for meaningful connections with teammates through our SocialSpace Community.

SimSpace is an Equal Opportunity Employer:

In compliance with federal law, all persons hired will be required to verify identity and eligibility to work in the United States and to complete the required employment eligibility verification document form upon hire.

SimSpace is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, pregnancy, genetic information, disability, status as a protected veteran, or any other protected category under applicable federal, state, and local laws. We are committed to providing an inclusive and welcoming environment for all members of our staff, clients, volunteers, subcontractors, vendors, and clients.

Research shows that women and people from underrepresented groups only apply to jobs if they meet all of the qualifications. However, no one ever meets 100% of the qualifications. SimSpace encourages you to break that statistic and to apply. We look forward to your application!

We also consider qualified applicants regardless of criminal histories, in accordance with applicable law. We are committed to providing reasonable accommodations for qualified individuals with disabilities in our job application procedures. If you need assistance or accommodation due to a disability, please contact careers@simspace.com.

SimSpace does not accept unsolicited resumes from employment agencies.

Actual compensation for the position is based on a variety of factors, including, but not limited to affordability, skills, qualifications and experience, and may vary from the range.