Senior Detection Engineer

Solutions³ LLC•Arlington, VA

3d•$131,000 - $150,000•Onsite

About The Position

Solutions³ LLC is supporting a U.S. Government customer with onsite incident response for civilian Government agencies and critical asset owners affected by cyberattacks. The work includes investigating breaches, characterizing their severity, developing mitigation plans, and assisting with service restoration. The Senior Detection Engineer develops, validates, deploys, and tunes detection logic for proactive threat hunting across federal and critical infrastructure environments. The role combines advanced threat-hunting tradecraft, adversary behavior analysis, and detection engineering to identify sophisticated threats, close visibility gaps, and improve detection effectiveness. The engineer translates threat intelligence, hunt findings, and incident-response lessons into behavioral analytics, investigative queries, and automation. Working across endpoint, network, identity, and cloud telemetry, the engineer selects detection methods based on available evidence and mission requirements. The position connects threat hunters, technical delivery teams, system engineers, analytics developers, and data scientists, translating operational findings into validated detections, automation, sensing improvements, and actionable capability requirements.

Requirements

Must be a U.S. citizen.
Must have an active TS/SCI clearance.
Must be able to obtain DHS Suitability prior to starting employment.
10+ years of directly relevant experience.
Demonstrated senior-level experience in threat hunting, detection engineering, incident response, or closely related defensive cyber operations, including independent ownership of production detection content.
Strong command of hypothesis development, adversary behavior analysis, iterative investigation, and evidence-based conclusions.
Proven ability to develop, test, deploy, and tune production detections, explain their limitations, and assess the effects of exclusions and suppression.
Advanced proficiency in one or more security query languages (KQL, SPL, EQL, ES|QL, or vendor-specific EDR languages), with the ability to adapt and optimize logic across platforms.
Experience analyzing process execution, command lines, process ancestry, authentication, persistence mechanisms, network connections, and related enterprise telemetry.
Understanding of Windows and Linux internals, enterprise networking, identity systems, cloud telemetry, and sophisticated adversary tradecraft.
Practical experience mapping detections to MITRE ATT&CK and explaining the telemetry, test evidence, and limitations behind coverage claims.
Proficiency in Python and PowerShell, or comparable languages, for analysis, enrichment, testing, and automation.
Ability to clearly document detection intent, logic, validation results, investigation steps, and tuning decisions.
Experience translating operational findings into engineering requirements and acceptance criteria, validating sensing effectiveness, and coordinating improvements across hunt analysts and delivery teams.
Bachelor’s degree in Engineering, Computer Science, Cybersecurity, Information Systems, or a related field.

Nice To Haves

Master’s degree preferred.
Experience with CrowdStrike Falcon, Microsoft Defender, Cortex XDR, SentinelOne, Elastic, Splunk, or comparable platforms.
Experience with portable detection content such as Sigma.
Experience with detection-as-code and automated testing.
SIEM data onboarding and pipeline tuning experience.
Experience with adversary emulation and cyber exercise development.
Federal civilian or critical infrastructure cyber operations experience.
Experience maintaining detection-engineering competencies, Job Qualification Requirements, training scenarios, and practical assessments.
GIAC Certified Detection Analyst (GCDA).
GIAC Certified Forensic Analyst (GCFA).
GIAC Defending Advanced Threats (GDAT).
GIAC Certified Intrusion Analyst (GCIA).
GIAC Certified Incident Handler (GCIH).
GIAC Cyber Threat Intelligence (GCTI).
Microsoft Certified: Security Operations Analyst Associate (SC-200).
Certified Information Systems Security Professional (CISSP).

Responsibilities

Develop and test hypotheses to uncover persistence, privilege escalation, credential access, lateral movement, command and control, and defense evasion; correlate evidence across data sources and document defensible conclusions.
Build behavioral analytics, correlation rules, signatures, and queries using endpoint, network, identity, cloud, and application telemetry, focusing on adversary techniques and activity sequences rather than individual indicators of compromise.
Convert validated hunt methods, incident findings, and exercise results into reusable detections; document each detection’s purpose, data requirements, investigative guidance, assumptions, and known limitations.
Translate capability gaps into technical requirements and acceptance criteria, recommend priorities through Threat Hunting governance, and verify that delivered capabilities meet operational needs.
Test detections against representative malicious and benign activity using historical telemetry, controlled simulations, and purple team exercises; verify intended behavior, evaluate evasion opportunities, and retain test evidence.
Analyze false positives, false negatives, alert volume, thresholds, exclusions, and environmental baselines; improve detection fidelity and alert context through enrichment and prioritization while assessing the risks of suppressing legitimate threat activity.
Assess the availability, reliability, and quality of sensors, tools, and data sources; identify collection, parsing, normalization, and retention gaps, explain their impact, coordinate remediation with infrastructure teams, and validate restored coverage.
Develop and maintain automation for enrichment, query execution, analytical workflows, and detection validation, including SOAR playbooks where applicable; tune data pipelines and queries for speed and responsiveness and build in review, error handling, and recovery procedures.
Maintain version-controlled content, peer reviews, release criteria, approval records, and rollback procedures; revalidate analytics after platform, schema, environmental, or adversary-tradecraft changes.
Coordinate with hunters, incident responders, intelligence analysts, and platform engineers to integrate detections into investigative and automated workflows.
Measure validated detection coverage, fidelity, actionable findings, and remaining gaps; communicate the operational significance of technical findings without equating rule counts with effective coverage.
Partner with analytics developers and data scientists to develop and validate advanced analytics, including machine learning where appropriate; assess operational value, false positives, data dependencies, and analytical limitations.
Provide technical leadership supporting the section focal point for vulnerability management and threat-hunting activities under applicable authorities.
Develop exercise scenarios and expected detection outcomes, assess sensing failures, and track corrective actions.
Evaluate new tools, data sources, and analytical methods against identified mission gaps; document test results, operational limitations, and adoption recommendations.
Review analytical work, mentor analysts, and set standards for query development, documentation, testing, deployment, and tuning.
Develop and maintain detection-engineering competencies, Job Qualification Requirements, training scenarios, and practical assessments in coordination with section leadership.