AppSec Engineer - Threat Modelling & Secure SDLC

Claranet limited; Lisboa; On-site; EUR 50,000 - 75,000; Full time

Job summary

Claranet limited in Lisbon is seeking an Application Security Engineer to join our internal team on site. You will support security assessments for new applications, review architectures and data flows, and identify vulnerabilities with mitigations throughout the lifecycle.

The role requires hands-on threat modelling, strong documentation, and experience integrating security tooling. Collaboration with development teams and audits is essential.

Qualifications

• 3–5 years of cybersecurity experience with proven application security expertise.
• Knowledge of ISO 27001 and OWASP Top 10.
• Hands-on threat modelling (STRIDE, LINDDUN or equivalent).
• Strong documentation and communication skills.

Responsibilities

• Supporting application security assessments for new applications and major changes.
• Analysing security requirements and reviewing architectures, data flows, interfaces and dependencies.
• Identifying vulnerabilities and recommending mitigations.
• Running Threat Modelling and embedding Security by Design across the project lifecycle.
• Validating implemented controls and issuing security recommendations to support go/no-go decisions.
• Producing clear technical reports and tracking findings until they are closed.
• Supporting the integration of AppSec tooling (SAST, DAST, SCA, IAST).
• Reporting on risk and maturity indicators, and supporting audits.

Skills

Application security

Threat modelling

Documentation

Communication

Education

Degree in Cybersecurity

Related field (CS/CE)

Tools

SAST

DAST

SCA

IAST

Job description

Claranet limited in Lisbon is seeking an Application Security Engineer to join our internal team on site. You will support security assessments for new applications, review architectures and data flows, and identify vulnerabilities with mitigations throughout the lifecycle.

The role requires hands-on threat modelling, strong documentation, and experience integrating security tooling. Collaboration with development teams and audits is essential.