Senior Security Engineer - Red Team (Remote)

Insider One; Fatih; Remote; TRY 600,000 - 900,000; Full time

Benefits offered by this job

Monthly meal allowance

Private health insurance

ESOP program

Professional training & L&D

Job summary

Insider One is hiring a Security Engineer - Red Team to advance our security program. You will perform penetration tests, review code, and help secure our platforms used by top brands globally. You will work with a fast‑moving, diverse team across Turkey on cutting‑edge AI and data projects.

We value strong English communication, hands‑on security testing, and the ability to translate findings into actionable fixes for developers. This fully remote role offers global impact and growth.

Qualifications

• 4+ years of web application security experience.
• Experience testing web apps, APIs, and mobile apps.
• Proficient in REST APIs and web services security.
• Familiar with SAST/DAST tools (Fortify, Veracode, Checkmarx).
• Knowledge of OWASP Top 10 and secure coding practices.
• Experience mentoring teams on secure SDLC and code reviews.

Responsibilities

• Conduct web/mobile application security tests and source reviews.
• Assist blue teams and stay updated on threats and trends.
• Produce detailed vulnerability reports with clear mitigation steps.
• Educate development teams on secure coding and testing practices.

Skills

Web security

REST APIs security

SAST/DAST tools

OWASP knowledge

Secure coding

SDLC guidance

Code review

Security research

English proficiency

Python/JS/PHP

AWS security

Security certifications

Team collaboration

Analytical thinking

Tools

Fortify

Veracode

Checkmarx

Job description

Before jumping into all the information about the role and what you can bring to the table, let us introduce ourselves real quick.

About us

Insider One is the #1 platform that brings everything marketing and customer engagement teams need in one place so they can reach their peak potential and become unstoppable.

Our story began with six desks and a vision to create a single platform to make industry-first technologies and emerging channels accessible to marketers worldwide. Today, Insider One is powered by 1,500+ team members representing 50+ nationalities across 30+ offices. With AI at its core and an integrated Customer Data Platform (CDP), Insider One unites data, personalization, and journey orchestration across the most extensive set of natively supported channels, including WhatsApp, SMS, Email, Web, App, and Site Search.

We recently raised one of the largest funding rounds in the industry, a $500M Series E led by General Atlantic. We are backed by top-notch investors, including Sequoia Capital, QIA, Riverwood, and Endeavor Catalyst, and trusted by 2000+ customers from high-growth startups to the most prestigious Fortune 500 companies such as Samsung, Nike, L’Oreal, Singapore Airlines, Nestlé, Nissan, Lenovo, Puma, IKEA, Allianz, Domino’s, and the list goes on.

Insider One was congratulated for becoming one of the only woman-founded, women-led B2B SaaS unicorns in the world. Loved by customers, recognized by analysts, we are the only vendor recognized as the #1 leader in all the capabilities marketing and customer engagement teams need. Don’t just take our word for it — see for yourself. We consistently outperform and continue our leadership, and the results speak for themselves.

From day one, Insider One’s mission has not only been to build a world-class product company, but also to create one of the most socially progressive technology communities in the world. Through our social responsibility initiatives like 100 Social Responsibility Projects, AI Training for Teachers, Code Academy, SheCodes, SheLeads, and SheMarkables, our community has committed to scaling its impact on our communities across 30+ countries, driving initiatives in health, education, farming, animal rights, and increasing women’s representation in STEM.

Behind all these achievements is an exceptionally talented, visionary team of overachievers that moves fast and agile, creating cutting-edge products, and focuses on making an impact. If you want to be a part of this journey, just keep reading.

And now? Now we are looking for a Security Engineer - Red Team who wants to take their career one step further. If you think you are one of those people, here you will have the chance to work with the world's leading brands with Artificial Intelligence & Machine Learning technologies. Right now, while you are reading this, we are sending an average of 2.2 billion requests and almost 2 billion instant notifications to more than 450 servers a day. On the Artificial Intelligence and Predictive side, we have more than 100 TB of historical data. We do not wait for jobs or opportunities to come to our feet, we create them. We have now reached 25% of global users. If all these interests you, read on for more!

Our Engineers and Software Developers always think with an innovative perspective, taking advantage of the inexhaustible power of the digital world. They create impressive and intelligent products like a true artist. Our Product and Development teams are located in our Istanbul and Ankara offices, so we produce and develop the technology we export to the world in our own country. As Insider One, we believe in cooperation and adapting the innovations brought by technology by acting fast. We work closely with other Departments with agile teams, and we are not afraid of getting our hands dirty. As we said; we do not wait for jobs or opportunities to come to our feet, we create them ourselves. You can check our Tech Stacks here!

What You Will Do

• performs web, mobile application, and internal penetration tests, source code reviews, threat analysis, social-engineering assessments,
• supports blue teams when needed,
• researches new attack vectors and stays current with cybersecurity news and trends,
• trains Quality Assurance and Development teams in standard security testing techniques and secure software development.

What You Will Need

• have 4+ years of working experience in web application security,
• have hands‑on experience in security testing of web applications, web services, mobile applications, APIs, etc.,
• have experience securing REST APIs and web services,
• have experience using and implementing SAST / DAST tools such as Fortify, Veracode, Checkmarx, or other similar tools,
• know how to conduct penetration tests of information systems using commercial and open-source exploitation tools,
• have a good understanding of standard security vulnerabilities and common remediation as published by OWASP, SANS, etc.,
• have experience working with secure coding methodology and best practices and their implementation within engineering teams,
• will support developers of our business units in their SDLC and provide guidance regarding mitigations to emerging threats,
• will review application source code based on static application security testing tools,
• will be engaging in security research to remain current on vulnerabilities and testing tools,
• will be creating detailed, professional documentation/reports that clearly communicate vulnerabilities, mitigation strategies, and remediation steps,
• have the ability to work on multiple projects concurrently and be committed to providing exemplary customer service,
• have strong written and verbal communication skills in English,
• have Python, JavaScript, PHP programming experience as a plus,
• have knowledge in scripting (any language) and experience in automation scripts for application security testing as a plus,
• have familiarity with cloud security, particularly AWS security concepts, as a plus,
• have certifications such as eWAPTx, OSCP, OSWE, etc., as a plus,
• are able to work in a team-centric environment,
• have strong critical thinking and analytical skills,
• have experience in executing white, gray, or black box security posture assessments and completing detailed reports that outline the findings and recommendations.

What We Offer

• Enjoy a monthly meal allowance designed to enhance your daily routine.
• Access comprehensive private health insurance.
• Feed your curiosity with access to Spotify, LinkedIn Learning, Blinkist, MasterClass, Neoskola, and CloudGuru.
• Level up with internal trainings covering AI fundamentals, coding, foreign languages, and a wide range of personal development skills.
• Be part of a diverse team that’s as global as it gets, where every voice is heard and 50+ nationalities build together.
• Become a Shareowner through our eligibility-based “ESOP” and own a piece of what you build.
• Help build the team you want to work with and enjoy rewarding referral bonuses.
• Opportunities to give back to your community through volunteering and purpose-driven social impact projects.
• From global retreats to team-building activities, expect year-round events that turn into lifelong memories.
• Get inspired by the greatest minds in the tech industry through events like our Tech & Dev Talks.
• Work from anywhere in Turkey through our fully remote setup.

We aren't just hiring for a position; we are hiring for a mission — a mission to build a lasting legacy that will set the benchmark for the most progressive tech companies out there.

To do this, we are looking for exceptional talent to join a community of good-hearted individuals who take high ownership and are relentlessly driven to go the extra mile.

If this sounds like who you are and where you aspire to be, we are excited to meet you.

We provide equal opportunity in a zero-discrimination workplace and not just welcome but also embrace everyone without regard to sex, race, color, nationality, religion, gender identity, sexual orientation, disability status, citizenship, or marital status.

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