Deirdre O'Callaghan
Senior Cyber Security Analyst | Threat Detection, Incident Response & Security Architecture
Blackwater Security Systems
Dear Hiring Manager,
I am writing to express my interest in the Cyber Security Analyst position at Blackwater Security Systems. With a background centered on threat detection, incident triage, and security operations maturity, I welcome the opportunity to contribute to your team's ongoing protection of enterprise infrastructure.
In my current role as Lead Cyber Security Analyst at Shannon River Technologies, I direct Tier 2 and Tier 3 incident response investigations across multi-cloud and on-premises environments. A significant part of my work involves refining detection mechanisms; by engineering and fine-tuning correlation rules within Splunk Enterprise Security, I decreased operational false positives by 38 percent. Furthermore, I facilitate quarterly purple team adversary simulation exercises to systematically benchmark detection posture against the MITRE ATT&CK framework and brief executive risk committees on incident post-mortems.
My operational background also includes leading technical implementations, such as spearheading the ingestion cutover of 14,000 corporate endpoints and cloud assets from legacy logging nodes to Splunk Cloud. During this project, I authored 65 custom alerting queries mapped to critical adversary behaviors to establish dependable detection pipelines. Combined with my prior experience supervising 24/7 security monitoring workflows and drafting forensic triage playbooks at Lee Valley Financial Systems, I bring disciplined methodologies for incident containment and threat analysis.
I would welcome the opportunity to discuss how my incident response experience and detection engineering background align with the operational needs of Blackwater Security Systems. Thank you for your time and consideration.
Yours sincerely,
Deirdre O'Callaghan