Staff Scanning Engineer

Company Background Censys’ mission is to be the one place to understand everything on the internet. Frustrated by the lack of trustworthy Internet intelligence, we set out to create the industry’s most comprehensive, accurate, and up-to-date map of the Internet. Today, Censys delivers real-time Internet intelligence and actionable threat insights to global governments, over 50% of the Fortune 500, and leading threat intelligence providers worldwide. Censys is building the most credible, robust map of the Internet through IP scanning, DNS lookups, web crawling, and the ingestion of millions of certificates. Censys was founded by security researchers who are passionate about developing technology that provides anyone the power to fully understand their digital risk and exposure. Individuals and enterprises–and anyone in between–can harness this power to discover new information and insight as the Internet, IoT and Cloud evolve. We are a true security startup with midwestern roots and we believe that a map of the Internet, or a map of your organization’s assets can quickly help guide organizations to the answers they need to protect themselves from vulnerability and risk. Location: This position is remote within the United States. Role Summary: We’re looking for a Staff Software Developer to help design, build, and operate the systems that power Censys’ Internet-wide scanning, DNS resolution, attribution, and data pipelines. This role sits at the intersection of backend engineering, distributed systems, and applied Internet research. You will work on production systems that discover, collect, validate, and enrich Internet-scale data across IPs, domains, certificates, services, and cloud infrastructure. You will help improve the accuracy, coverage, freshness, and reliability of the Internet Map that powers Censys’ products and research. At Censys, we work iteratively, but we are always thinking about the big picture. We’re expanding our scanning and data platform to make the Internet more explainable: richer context, better attribution, clearer relationships, and higher-confidence signals. We’re looking for someone with deep technical ownership, strong production engineering instincts, curiosity about how the Internet works, and the ability to mentor others while building reliable systems. What You’ll Do: • Design, build, and operate Internet-scale scanning, DNS, crawling, attribution, and data collection systems. • Own production backend services and pipelines that collect, process, validate, and enrich massive Internet datasets. • Improve the quality, freshness, reliability, and coverage of Censys’ Internet Map. • Build systems that support IP scanning, DNS lookups, protocol fingerprinting, asset attribution, and large-scale data ingestion. • Lead technical design for distributed services, streaming pipelines, storage systems, caching layers, scheduling systems, and scan orchestration infrastructure. • Partner with Research, Product, Security, and Engineering teams to turn research ideas into safe, scalable, production-ready systems. • Make thoughtful tradeoffs around reliability, cost, scale, latency, data quality, and operational complexity. • Participate in operational ownership of the systems you build, including observability, incident response, and on-call rotation. • Mentor engineers, review designs, and help raise the technical bar for backend and scanning infrastructure. Skills You Have: • 10+ years of software engineering experience building production systems. • Strong backend engineering experience in systems such as data ingestion pipelines, scanning systems, crawlers, schedulers, APIs, storage systems, or high-throughput services. • Experience designing and operating systems that handle large-scale data, high request volume, or Internet-scale workloads. • Strong programming experience; we primarily use Go. • Experience with cloud infrastructure such as AWS, GCP, or Azure. • Experience with message queues or streaming systems such as Google Pub/Sub, Kafka, Kinesis, or similar technologies. • Experience with distributed databases or large-scale storage systems such as Bigtable, Spanner, HBase, Cassandra, Postgres, or similar. • Strong understanding of reliability, observability, testing, deployment, and operational ownership. • Ability to write understandable, testable, maintainable code. • Strong technical communication skills, with the ability to explain complex systems to engineers, product managers, researchers, and leadership. • Good judgment around when and how to use AI-assisted development tools. Things that make you stand out: • Experience building or operating scanners, crawlers, DNS infrastructure, passive/active measurement systems, or Internet data collection platforms. • Deep understanding of DNS and how it is used in practice, including resolution, delegation, record types, nameservers, and operational edge cases. • Knowledge of Internet protocols, service discovery, network measurement, protocol fingerprinting, or large-scale crawling. • Experience with attribution systems, asset mapping, cloud asset discovery, or connecting Internet-facing services back to organizations. • Experience turning research prototypes into reliable, maintainable production systems. • Familiarity with gRPC, REST, Protobuf, MessagePack, or other API and serialization technologies. • Experience building, deploying, and maintaining containerized services in Kubernetes. • Experience with scan orchestration, scheduling, rate limiting, backpressure, retries, deduplication, or distributed task execution. • Experience working across the boundary of research and engineering, especially in security, infrastructure, networking, or Internet measurement. • Curiosity about how the Internet works and a desire to build systems that make it more understandable. For high cost of living areas (San Francisco Bay, New York City, and Seattle), the expected salary range for this position is $198,000 USD – $233,000 USD, plus bonus eligibility and equity. For all other US locations, the expected salary range for this position is $172,000 USD – $216,000 USD, plus bonus eligibility and equity. Job level and actual compensation will be decided based on factors including, but not limited to, individual qualifications objectively assessed during the interview process (including skills and prior relevant experience, potential impact, and scope of role), market demands, and specific work location. The listed range is a guideline, and the range for this role may be modified. For roles that are available to be filled remotely, the pay range is localized according to employee work location by a factor of between 83% and 100% of range. Please discuss your specific work location with your recruiter for more information. Censys offers a competitive benefits package to employees, including equity, health, dental & vision coverage, retirement with company contribution, parental leave, mental health & wellness benefits, flexible PTO, and a professional development stipend. Censys also offers sales incentive pay for most sales roles and an annual bonus plan for eligible non-sales roles. Censys’s compensation and benefits are subject to change and may be modified in the future. Please see our careers page for more details. We will work to ensure individuals with disabilities are provided reasonable accommodation to apply for a role, participate in the interview process, perform essential job functions, and receive other benefits and privileges of employment. If you require accommodation, please reach out to your recruiter. These modifications enable an individual with a disability to have an equal opportunity not only to get a job, but successfully perform their job tasks to the same extent as people without disabilities. To ensure the integrity of our hiring process and facilitate a more personal connection, we require all candidates to keep their cameras on during video interviews. Additionally, if hired, we would love to bring you to our HQ in Ann Arbor for in-person onboarding. By applying for this job, the candidate acknowledges and agrees that any personal data contained in their application or supporting materials will be processed in accordance with our Censys Privacy Policy. Our roots are in Ann Arbor, Michigan and our innovation is fueled by the team’s global perspectives. For this role, we are open to remote employees across the continental US. We value diversity and are committed to creating an inclusive environment for all employees. Censys is an equal opportunity employer. Note to external recruiters/agencies: We are not currently engaging with third-party agencies for this role and will not accept unsolicited outreach. We kindly ask that you do not submit resumes or candidate profiles to our team. Identity Verification As part of our hiring process, all candidates who receive an offer of employment will be asked to complete an identity verification through CLEAR. California Privacy Rights Notice Pursuant to the California Consumer Privacy Act (CCPA), we are providing you with notice that we collect personal information from job applicants for business purposes, including evaluating your candidacy for employment, conducting interviews, and, if applicable, completing the hiring process. The categories of information we may collect include identifiers (such as name and contact information), professional or employment-related information (such as work history, education, and references), and other information you provide in your application. We do not sell or share your personal information. For more information on how we use and protect your personal information, and your rights under the CCPA, please refer to our Privacy Policy.