Cybersecurity Senior Offensive & Defensive Engineer(Oniste)

Nexsoll is a dynamic digital innovation company dedicated to helping organizations accelerate growth through strategic digital marketing, lead generation, and enhanced customer engagement. Established in 2024, we prioritize the trust our users place in us by safeguarding their data with the utmost commitment. We are seeking a highly skilled security expert who approaches challenges like an attacker but builds defenses with the precision of an engineer. This role demands vigilance and creativity to protect our systems against sophisticated, large-scale cyber threats.

Key Responsibilities

Hunt for critical bugs: Conduct comprehensive penetration testing and code reviews across web applications, APIs, mobile platforms, cloud infrastructure, and internal networks to identify vulnerabilities before they can be exploited.

Think like the adversary: Lead red team exercises simulating real-world attack scenarios, including initial access, privilege escalation, lateral movement, and data exfiltration, to expose and address security weaknesses.

Build layered defenses: Design and implement defense-in-depth strategies such as Web Application Firewalls (WAF), rate limiting, bot mitigation, DDoS protection, zero-trust access models, and network segmentation.

Harden everything: Secure cloud environments (AWS, Azure, or GCP), container orchestration platforms, CI/CD pipelines, secrets management, and identity and access management systems.

Detect and respond: Establish monitoring systems, Security Information and Event Management (SIEM), and alerting mechanisms. Develop and maintain incident response playbooks to ensure rapid detection and containment of threats.

Secure the code: Collaborate with development teams to integrate security into the software development lifecycle through threat modeling, static and dynamic application security testing (SAST/DAST), dependency scanning, and secure code reviews.

Lead incident response: Act as the primary point of contact during security incidents, managing containment, investigation, and remediation efforts to prevent recurrence.

Raise the bar: Train engineering teams, define security standards, and foster a security-first culture that supports innovation without becoming a bottleneck.

Required Qualifications

- Minimum of 7 years of hands-on experience in offensive and/or defensive cybersecurity roles.
- Proven track record of discovering critical vulnerabilities, demonstrated through CVEs, bug bounty Hall of Fame entries, published research, or successful penetration tests.
- In-depth understanding of OWASP Top 10 vulnerabilities, API security, authentication and authorization flaws, injection attacks, SSRF, deserialization, and business logic vulnerabilities.
- Proficiency with security tools such as Burp Suite, Metasploit, Nmap, Ghidra/IDA, Cobalt Strike, or equivalents.
- Strong cloud security expertise with AWS, Azure, or GCP, including container and Kubernetes hardening.
- Experience defending against large-scale attacks such as DDoS, credential stuffing, bot attacks, and automated exploitation.
- Ability to develop scripts and tools using Python, Go, Bash, or similar languages to automate defenses.
- Excellent communication skills, capable of articulating complex security risks to both technical teams and executive leadership.
- Relevant certifications such as OSCP, OSCE³, OSEP, OSWE, GXPN, CRTO, or equivalents.

Preferred Qualifications and Benefits

- Recognized rankings on platforms like HackerOne, Bugcrowd, or Intigriti, or achievements in Capture The Flag (CTF) competitions.
- Contributions to the security community through published CVEs, research papers, or presentations at conferences such as DEF CON, Black Hat, or BSides.
- Familiarity with compliance frameworks including SOC 2, ISO 27001, and PCI-DSS.
- Experience in malware analysis, reverse engineering, or threat intelligence.
- Competitive salary with performance-based bonuses.
- A leadership team that prioritizes and values security at every level of the organization.

This role offers a unique opportunity to shape the security posture of a fast-growing digital firm while working alongside passionate professionals committed to innovation and excellence. If you are driven to outthink attackers and build resilient defenses, Nexsoll welcomes your expertise.