RapidFort, Inc.

You would maintain bare-metal, virtualized, and cloud infrastructure while handling network design, incident response, automation, reliability, and security. | The role requires 8+ years of hands-on Linux administration, including deep kernel, networking, and storage knowledge, plus scripting, configuration management, security, and cloud infrastructure experience. | Location: Remote — United States Department: Information Technology — Infrastructure Engineering Reports to: Infrastructure Engineering Manager Employment Type: Full-time, individual contributor Experience: 8+ years of relevant hands-on experience Base Salary: $125,000–$165,000 annually, plus equity and benefits Eligibility: U.S. citizenship required Senior Linux Systems Administrator RapidFort, Infrastructure ======================================================================= ABOUT RAPIDFORT --------------- RapidFort helps enterprises and government organizations reduce software supply-chain risk through hardened container images, runtime-based attack surface reduction, and automated vulnerability remediation. We own and operate the infrastructure that supports our engineering teams and core systems. ABOUT THE ROLE -------------- RapidFort is looking for a senior Linux systems administrator to own and run its infrastructure: bare-metal Linux servers in data centers, the virtual machines and containers that run on them, the networks that connect them to each other and to our staff, self-hosted development services such as GitLab and CI, and our resources in AWS. You will keep these systems reliable, secure and documented, plan and carry out changes to them, and lead the response when something breaks. This is a hands-on senior individual-contributor role with direct responsibility for technical execution. We need someone whose knowledge runs from disks and kernels up to routing tables, firewalls and DNS. RESPONSIBILITIES ---------------- Linux systems administration - Build, configure, administer and harden Linux systems: installation, system services, packages, users, permissions, authentication and access control. - Operate a fleet of remotely managed physical Linux servers and the virtual machines and containers on them: storage, capacity planning and hardware replacement. - Own the operating-system lifecycle: patch testing, staged deployment, operating-system and kernel upgrades, tracking exceptions, and moving systems off releases that reach end of life. - Keep configurations consistent, and find and correct configuration drift. Networks, cloud and development services - Design, run and troubleshoot the network: routing, traffic shaping, firewalls, DHCP and DNS, and the overlay network that connects the data centers, the cloud and remote staff. - Manage our resources in AWS, mainly EC2 and S3. - Run the self-hosted development services, including GitLab, CI runners, build machines and package mirrors. Troubleshooting and incident ownership - Independently diagnose production problems involving CPU, memory, disk I/O, filesystems, systemd, networking and service dependencies, such as failed services, boot problems, resource exhaustion, package conflicts and intermittent performance issues. - Use logs, metrics and command-line tools to find root causes and to confirm that a fix worked. - Monitor the systems, and improve monitoring and alerting so that problems are caught early without needless noise. - Lead incident response, contribute to incident reviews, and complete the corrective actions that keep a problem from recurring. - Work with developers, IT, data-center staff and hardware vendors when a problem crosses system boundaries. - Escalate when needed, with clear findings, the supporting evidence, and a record of the troubleshooting already done. Automation and configuration management - Write, debug and maintain Bash scripts for provisioning, diagnostics, remediation, reporting and routine operations, and Python automation where it makes operational work more reliable or simpler. - Write and maintain Ansible roles and playbooks to the team's standards. - Replace repetitive manual tasks with reliable, maintainable automation. - Keep configuration and automation in git, test changes, and make changes through merge requests, review and automated deployment rather than by editing live systems. Security and operational reliability - Own access control and security: SSH keys and hardware security keys, network access policies, least privilege, security baselines, timely patching, vulnerability scanning, audits of exposed services, and software supply-chain risk. - Run the backups and prove that they restore. - Plan changes and maintenance with a written procedure that gives the steps, how to check the result, and a way back. - Write and maintain documentation, including runbooks, configuration records and troubleshooting notes, and review other engineers' changes. - Take part in a shared on-call rotation and in scheduled maintenance windows. REQUIRED EXPERIENCE AND SKILLS ------------------------------ Typically eight or more years administering Linux servers in production with root responsibility, including physical hardware and not only cloud instances, with recent hands-on responsibility for operations and troubleshooting. Solid working knowledge of most of the following. Linux systems - Linux processes, services, users and permissions, package management, filesystems and logging, in depth. - Strong experience with Debian and other Linux distributions. - Boot and kernel: UEFI, GRUB, initramfs, kernel configuration and building, kernel modules (including DKMS) and sysctl. - Resource control and diagnosis: cgroups v2, memory management and the out-of-memory killer, pressure-stall information (PSI), and tools such as strace, perf, iostat, ss and /proc. - Both systemd and sysvinit. Networking - TCP/IP fundamentals: IPv4 and IPv6, subnetting, bridges, VLANs, bonding and NAT, and troubleshooting connectivity. - Linux routing: multiple routing tables, policy routing with ip rule, source-based routing, and routing between sites. - Traffic shaping with tc: queueing disciplines (HTB, fq_codel, cake), classification with tc filters or firewall marks, and ingress shaping through ifb. - nftables, including sets, maps and connection tracking, and enough iptables to read and migrate older rule sets. - DNS and DHCP: unbound as a validating recursive resolver with local zones and forwarding, dnsmasq for DHCP and local DNS, split-horizon DNS, and debugging name resolution with dig. - WireGuard, and NetBird or a similar WireGuard-based overlay network such as Tailscale or Headscale: peers, groups, access policies, routing peers for subnets, and DNS. Experience self-hosting the control plane is a plus. - Reading packet captures with tcpdump or Wireshark. Storage - ZFS in depth: pool layout, datasets and zvols, snapshots, send and receive, scrubs and resilvering, ARC tuning, and recovering a degraded or damaged pool. - mdadm RAID, LVM, ext4 and XFS, filesystem repair, SSD caching such as bcache or dm-cache, and handling failing disks (SMART, NVMe health). Virtualization and containers - KVM/QEMU or Xen, LXC and Docker, and enough Kubernetes to debug a cluster. Monitoring and backups - Monitoring and alerting, and backup and recovery, including testing that restores work. AWS - EC2: instances, images, security groups, EBS, instance profiles and the instance metadata service (IMDSv2). - S3: bucket policies, versioning, lifecycle rules and encryption. - IAM roles and policies written to the principle of least privilege. Git, GitLab, GitOps and configuration management - Expert git: branching, merging and conflict resolution in a merge-request workflow, without rewriting or destroying history. - GitLab administration: a self-hosted installation and its upgrades, groups, projects and permissions, protected branches, approval rules, and CI/CD pipelines and runners. - GitOps and infrastructure as code: configuration that lives in git and is applied automatically after review, drift detection, and OpenTofu or Terraform. - Writing and maintaining Ansible roles and playbooks, or substantial experience with a comparable configuration-management tool. Security - Host hardening, least privilege, firewall design, and finding and closing services that are exposed by mistake. - SSH in depth: sshd configuration, SSH certificates, and FIDO2 hardware keys such as YubiKeys. GPG signing and verification. - TLS certificates and their renewal, and safe handling of secrets. - Patch management, vulnerability scanning, software supply-chain risk, and investigating incidents from logs. Scripting - Expert Bash: robust scripts with sound error handling, quoting, traps, and commands run over SSH, which you can write, troubleshoot and maintain in production on your own. - Good working Python for systems automation and operational tooling. Judgment and communication - A record of personally resolving complex technical problems and following through on the corrective actions. - Sound judgment about change risk, testing, rollback and escalation. - Clear, precise written English for change plans, incident reports, reviews, tickets and documentation. - The ability to work independently within a remote team. PREFERRED --------- - Server hardware: IPMI, iDRAC, iLO and other BMC consoles, RAID and HBA controllers, and firmware updates. - Diagnosing PCIe devices and their drivers and firmware from kernel logs. - Physical data-center work, and working with data-center remote hands. - GPU servers, NVIDIA drivers and CUDA environments, and infrastructure for AI workloads. - Other virtualization platforms, such as Proxmox or VMware. - SAN and NAS storage, and multipathing. - Monitoring and host intrusion detection, such as Prometheus, Grafana, netdata or Wazuh. - Jenkins or other build farms, and caching mirrors or proxies for apt, PyPI, npm or Maven. - Backup tools such as restic, borg or ZFS replication. - Infrastructure that supports SOC 2 or ISO 27001 controls. - Debian and its derivatives. - Other cloud providers, such as Linode.

You would build and maintain hardened container images, manage vulnerability remediation, and automate secure image build, testing, and publishing pipelines. | The role requires 5+ years in software or Linux systems engineering, deep containerization and security expertise, Linux package management, scripting with Python or Go, and vulnerability scanning experience. | Senior Software Engineer — Container Images & Security Citizenship Requirement: U.S. citizenship is required for this position due to work supporting federal government customers. Location: Remote Team: Engineering / Curated Images Employment Type: Full-Time About the Role RapidFort is looking for a hands-on Senior Software Engineer to join our Curated Images team and help build, secure, and maintain production-ready container images at scale. This role combines deep Linux engineering, vulnerability remediation, and software automation. You will own the container image lifecycle—from building minimal, reproducible images to analyzing and remediating CVEs, validating runtime compatibility, and automating ongoing maintenance and publishing. You will work closely with engineering, infrastructure, and security teams to deliver secure, reliable images across Linux distributions and application stacks, including Python, Go, and Java. Success requires the ability to investigate package and dependency issues, implement fixes, and build automation that makes those fixes repeatable. What You’ll Do Design, build, and maintain minimal, hardened container images across Linux distributions and application runtimes. Own end-to-end CVE remediation across OS packages, libraries, runtimes, and dependencies, including analysis, patching, rebuilding, and validation. Troubleshoot complex package compatibility, dependency, build, and runtime issues while preserving application functionality. Reduce image attack surface and size by removing unnecessary packages, binaries, and dependencies. Build and improve automated pipelines for image builds, vulnerability scanning, remediation, testing, and publishing. Develop tooling to manage image versioning, dependency updates, metadata, and release traceability. Generate, validate, and maintain SBOMs to support software supply chain visibility and compliance. Validate image functionality, reproducibility, and compatibility with Kubernetes and other containerized environments. Collaborate with platform, infrastructure, and security teams to define image hardening standards and integrate curated images into development and deployment workflows. Maintain clear documentation that helps developers adopt and use curated images. Continuously improve remediation speed, image quality, build reliability, and operational efficiency. What You Bring 5+ years of relevant experience in software engineering, Linux systems engineering, platform engineering, DevSecOps, or SRE. Deep understanding of Linux systems, with hands-on experience across distributions such as Debian, Ubuntu, Alpine, or RHEL. Strong experience building and optimizing Docker images, including multi-stage builds, image layering, and container filesystem structures. Proven experience investigating and remediating CVEs in Linux packages and container images, including patching, rebuilding, and validating fixes. Strong working knowledge of Linux package management and dependency resolution using tools such as apt, apk, yum/dnf, or rpm. Strong programming or scripting skills in Python, Go, or Bash, with experience building maintainable automation and internal tooling. Experience developing and maintaining CI/CD pipelines using GitHub Actions, GitLab CI, Jenkins, or similar tools. Hands-on experience with vulnerability scanners such as Trivy, Grype, or Clair, along with SBOM generation. Solid understanding of Kubernetes concepts, container lifecycles, and image deployment requirements. Ability to independently troubleshoot complex technical issues and collaborate effectively across engineering teams. Nice to Have Experience building minimal or distroless images and maintaining a large catalog of container images. Experience building Linux packages from source or backporting security fixes. Familiarity with SBOM formats and tools such as SPDX, CycloneDX, and Syft. Experience with image signing, provenance, and verification using Cosign or Sigstore. Knowledge of software supply chain security frameworks such as SLSA. Familiarity with container registries such as Docker Hub, Harbor, or Amazon ECR. Experience with Helm, Kustomize, GitOps, or infrastructure-as-code workflows. Experience in a startup environment or regulated industry. What Success Looks Like Reliable delivery of production-ready, hardened images with near-zero exploitable CVEs. Scalable automation for image builds, remediation, validation, and publishing. Faster remediation turnaround while maintaining runtime compatibility and image quality. Measurable reductions in image size and attack surface. Repeatable standards for secure, reproducible container image delivery. Compensation & Benefits Base salary: $130,000–$200,000, depending on experience and technical depth. Equity participation. Comprehensive health, dental, and vision coverage. Remote-first work environment. Opportunity to solve complex Linux, container, and software supply chain security challenges. Career growth within a rapidly scaling cybersecurity company.

Design and maintain backend services and distributed systems for a cybersecurity platform. | 5+ years backend engineering experience with Python, Go, or C++, Linux, Kubernetes, and distributed systems. | Senior Software Engineer – Security & Distributed Systems Location: United States — Remote Department: Engineering Company: RapidFort Employment Type: Full-Time U.S. Citizenship: Required About RapidFort RapidFort is a cybersecurity company focused on securing and optimizing modern software supply chains and cloud-native environments. Our technology helps organizations reduce software vulnerabilities and attack surface by identifying and removing unnecessary components from containerized applications. RapidFort works with enterprise and U.S. public-sector customers operating highly complex, security-sensitive environments. We are building systems that operate at the intersection of cybersecurity, distributed systems, Linux, containers, Kubernetes, and cloud infrastructure. The Role RapidFort is looking for a Senior Software Engineer – Security & Distributed Systems to join our engineering team. This is a hands-on backend engineering role for someone who enjoys solving complex systems problems and building production software that operates across distributed, containerized environments. You will design and develop backend services and distributed systems that power RapidFort’s security platform, working with large volumes of software, vulnerability, container, and runtime data. This is not an SRE or infrastructure operations position. We are looking for a software engineer who builds systems and products, with strong knowledge of the infrastructure and environments in which those systems operate. What You’ll Do Design, build, and maintain highly reliable backend services and distributed systems. Develop core components of RapidFort’s cybersecurity and software supply chain security platform. Build systems for processing, analyzing, and managing large volumes of security, vulnerability, package, container, and runtime data. Design scalable APIs, services, data pipelines, and internal platform components. Develop software that operates across Linux, containerized, Kubernetes, and cloud environments. Solve complex problems involving concurrency, performance, scalability, reliability, and distributed processing. Work with container images, software packages, dependencies, vulnerabilities, SBOMs, and other software supply chain data. Improve the performance and efficiency of systems handling large-scale security analysis and remediation workflows. Diagnose complex problems across applications, operating systems, containers, networks, and distributed services. Design systems with security, reliability, observability, and fault tolerance built in from the beginning. Write clean, maintainable, well-tested production code. Participate in architecture and technical design discussions. Review code and help establish strong engineering practices across the team. Work closely with security researchers, product managers, and other engineers to turn complex security problems into scalable product capabilities. Take ownership of projects from technical design through production deployment. What We’re Looking For 5+ years of professional software engineering experience, ideally building backend platforms or distributed systems. Strong programming experience with Python, Go, C++, Java, or similar backend/system-level languages. Deep understanding of distributed systems and production backend architecture. Strong knowledge of Linux systems and internals. Experience building APIs, backend services, microservices, or large-scale data-processing systems. Hands-on experience with Docker, containers, and Kubernetes. Experience designing software for cloud environments such as AWS, Azure, or GCP. Strong understanding of networking, processes, filesystems, memory, CPU utilization, and system performance. Experience with relational and/or NoSQL databases and large-scale data systems. Understanding of concurrency, asynchronous processing, queues, caching, and distributed workloads. Strong debugging and problem-solving skills across multiple layers of a technology stack. Ability to independently own complex engineering problems from design through implementation. Strong written and verbal communication skills. Security Experience You do not need to be a traditional security engineer, but you should be interested in building software that solves difficult cybersecurity problems. Experience in one or more of the following areas is highly valuable: Software supply chain security Application or cloud security Vulnerability management Container security Kubernetes security Software composition analysis SBOMs and software dependency analysis CVEs and vulnerability intelligence Linux security DevSecOps Package management and software build systems Runtime security or workload analysis Preferred Qualifications Experience building security products or developer/security infrastructure. Experience working with very large software or vulnerability datasets. Deep understanding of container images, registries, layers, packages, and dependencies. Experience with Kubernetes internals and container runtimes. Knowledge of Linux package ecosystems such as RPM, DEB, APK, or similar. Experience with CI/CD systems and modern software build pipelines. Experience profiling and optimizing CPU, memory, disk, and network performance. Familiarity with open-source security tooling and vulnerability databases. Experience building highly available systems operating across multiple environments or clusters. Experience in a high-growth cybersecurity, cloud infrastructure, or enterprise software company. Compensation The expected base salary range for this position is $150,000–$200,000 USD annually. Actual compensation will be determined based on the candidate’s experience, technical depth, qualifications, geographic location, and overall fit for the position. Additional compensation may include equity and other company benefits. U.S. Citizenship Requirement U.S. citizenship is required for this position due to RapidFort’s work with U.S. government and Department of Defense customers and the potential for this role to support security-sensitive public-sector environments. Why RapidFort This is an opportunity to work on technically challenging problems at the intersection of cybersecurity, distributed systems, containers, Kubernetes, Linux, and software supply chain security. You’ll work directly with experienced engineers and company leadership while having meaningful ownership over the architecture and implementation of systems that protect real-world production environments. At RapidFort, senior engineers are expected to do more than execute tickets. You will help define technical solutions, influence architecture, solve difficult engineering problems, and build technology that becomes a core part of the RapidFort platform. Benefits RapidFort offers a competitive compensation and benefits package, including: $150,000–$200,000 base salary Equity participation Medical, dental, and vision coverage Paid time off and company holidays Remote-first work environment Flexible working arrangements Professional development and career-growth opportunities Opportunity to work on advanced cybersecurity and cloud-native technology Significant technical ownership and direct access to senior engineering leadership RapidFort is an equal opportunity employer. We value diverse perspectives and are committed to building an inclusive workplace.