Senior Software Engineer, Backend

OpenKrill; United States; On-site; USD 120,000 - 180,000; Full time

Benefits offered by this job

Health & Wellness benefits

Mental Health Support

Performance bonuses

Job summary

SimSpace is seeking a Senior Software Engineer, Backend, to build the orchestration engine at the core of our internet simulation platform. You will own the control plane API, drive an event-driven architecture, and ensure reliable storage, deployment, and cross-team collaboration across multi-range deployments.

You’ll apply strong Kubernetes expertise, GitOps practices, and API design discipline to deliver scalable, multi-tenant capabilities with operational rigor.

Qualifications

• Backend development experience from scratch in a production-grade system.
• Proficiency with Kotlin and Spring Boot.
• Strong knowledge of distributed systems, APIs, and Kubernetes.

Responsibilities

• Design and build the control plane API: interface used by range orchestration and scenario systems.
• Own the event-driven orchestration layer coordinating multi-step operations across subsystems.
• Build and maintain the platform's persistent storage layer for services and data.
• Own the deployment model for the platform: Kubernetes operators and upgrade strategies.
• Define and own the state model and recovery/convergence logic of the platform.
• Collaborate with the network simulation team on the in-range proxy agent architecture.
• Partner with SRE on runbooks, incident response, and observability instrumentation.
• Contribute to configuration management, secrets handling, and security posture.

Skills

Backend development

Kotlin

Spring Boot

API design

Distributed systems

Event-driven architectures

Kubernetes

Storage systems

Observability/runbooks

GitOps

Tools

Kubernetes operators

CI/CD tooling

Job description

SimSpace serves as an AI Proving Ground where organizations can confidently train, test, and outmaneuver adversaries in any environment. Trusted by allied governments, militaries, enterprises, and research institutions worldwide, SimSpace enables adaptive, AI-ready defenses that stay ahead of evolving threats. Founded in 2015 by experts from U.S. Cyber Command and MIT Lincoln Laboratory, the platform unifies training, testing, and validation in a realistic, live-fire simulation—helping teams evaluate security investments, optimize performance, and compress cyber readiness cycles from months to days.

Why join SimSpace? We are an organization that is focused on building our culture and mindfully enhancing our atmosphere every day which is why we have collaborated on an integral value system. Our governing philosophy of being Human Centered is deeply embedded within our value system. We apply this philosophy to every one of our internal team members, external clients, and their customers.

How Do We Work? We believe that people are at the center of everything we do. SimSpace fosters a culture of continuous learning, curiosity, and professional growth. That belief shows up in action: in-house training, internal and external learning platforms, cyber conferences, industry events, and dedicated time for skill development. Our people are empowered to shape their careers - and it shows. Year over year, SimSpace consistently outperforms industry benchmarks in internal mobility, promotions, and total rewards growth.

Who Thrives Here? We are a team of innovators, protectors, and problem‑solvers. We believe diversity of thought and experience fuels better solutions, and we’re committed to building teams that reflect the communities we serve. Whether you’re remote or office-based, you’ll collaborate with talented colleagues across departments and time zones, united by the mission to create a safer digital world.

We are looking for a Senior Software Engineer to build the orchestration engine at the heart of SimSpace's internet simulation platform. Every action in the platform, standing up a simulated service, registering a persona, pushing a topology update to a range, delivering a file to a scenario, provisioning a SaaS application, flows through the control plane this engineer owns. Where the other engineering roles on the team build the simulation layers themselves, this role builds the system that ties them together: the API surface that external systems call, the event-driven backbone that coordinates actions across subsystems, and the deployment and operational model that keeps a complex, multi-tenant platform running reliably across many concurrent range deployments. If you are energized by building systems that other engineers depend on and have strong instincts for distributed systems correctness and operational rigor, this role is for you.

THE TEAM IS RESPONSIBLE FOR:

• The control plane API: the external-facing interface through which range orchestration, scenario management, and user emulation systems drive the internet simulation platform, creating services, registering personas, updating topology, and querying state
• The event-driven orchestration backbone that coordinates actions across the platform's simulation layers, network, services, identity, and storage, and maintains consistent state across a distributed, multi-range deployment
• Persistent storage infrastructure for the platform: service data, content corpora, certificate stores, topology state, and the volumes that simulated services depend on
• The deployment and operational model for the internet simulation platform itself as a long-lived Kubernetes-native product, including upgrade paths, multi-range scaling, and the configuration model for new range integrations
• In-range proxy agent infrastructure in collaboration with the network simulation tech lead: the components that bridge the control plane to individual range deployments and maintain platform presence within each range

WHAT WILL YOU BE DOING AS A SENIOR SOFTWARE ENGINEER, BACKEND SIMSPACE?

• Design and build the control plane API: the interface that range orchestration and scenario systems use to drive the internet simulation platform, with strong attention to idempotency, consistent error semantics, and the operational patterns that make a platform API pleasant to build on
• Own the event-driven orchestration layer that coordinates multi‑step operations across the platform's subsystems, ensuring that standing up a new range, registering a persona, incorporating a SaaS application, or updating topology propagates correctly and completely across all components
• Build and maintain the platform's persistent storage layer, providing reliable, well-abstracted storage primitives for the services and subsystems that depend on it, across file, object, and container storage as requirements evolve
• Own the deployment model for the internet simulation platform itself: the Kubernetes operators or controllers that manage platform lifecycle, the upgrade and rollout strategy for a service that cannot afford downtime, and the configuration model for integrating new ranges
• Define and own the state model for the platform, what is authoritative where, how components recover from partial failures, and how the platform converges to a correct state after disruption
• Collaborate with the network simulation tech lead on the in-range proxy agent architecture, owning the infrastructure side of that interface: agent deployment, connectivity management, and the handoff model when an agent loses contact with the control plane
• Partner with the SRE team on the operational model for a new platform service, establishing runbooks, incident response procedures, and the observability instrumentation that makes the platform debuggable in production
• Contribute to cross‑cutting concerns including configuration management, secrets handling, and the security posture of the control plane

WHO YOU ARE:

• Experience Building backend from scratch, preferably using Kotlin and Spring Boot
• Strong API design instincts, you have built platform APIs that other engineers depend on and understand what makes an API surface reliable, consistent, and operationally sound over time
• Solid distributed systems fundamentals: you can reason clearly about consistency, failure modes, and convergence in a system where a central control plane coordinates distributed components that may lose connectivity or fail mid‑operation
• Experience building event‑driven or message‑driven systems, with an understanding of the tradeoffs involved in different coordination approaches, the implementation will be informed by the architecture, not the other way around
• Strong Kubernetes expertise including writing operators or controllers, managing custom resources, and reasoning about multi‑tenant workload isolation
• Experience designing and operating storage systems across different storage paradigms, file, object, and block or container storage, and choosing the right abstraction for each use case
• Operational rigor: you instrument what you build, write runbooks, and think about failure modes before they become incidents
• Experience with air‑gapped or on‑premises Kubernetes deployments is a strong plus given SimSpace's customer and deployment model
• Familiarity with infrastructure‑as‑code and GitOps‑based deployment workflows

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

• Compensation. Base monthly pay range: 1,500,000 CRC - 2,500,000 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 co