Flutter Mobile Developer Needed for In-App Purchase Flow

Keystone Digital

Contract · Remote · Flexible hours

About the role

Keystone Digital is launching a security hardening initiative for its cloud‑hosted applications. We need a Flutter Mobile Developer to build and secure the new "AegisVault" module, a client‑side encryption layer for our SaaS product. You will work closely with our DevSecOps team to embed security best practices directly into the mobile codebase.

Key responsibilities

• Design and implement the AegisVault Flutter module using Dart 3 and the latest Flutter SDK.
• Integrate end‑to‑end encryption APIs (AES‑256, RSA) and perform key management via AWS KMS.
• Conduct static analysis with SonarQube and remediate identified security issues.
• Set up CI pipelines in GitHub Actions to run security scans on each PR.
• Collaborate with backend engineers to ensure secure data transmission over TLS 1.3.
• Deliver a functional prototype within 8 weeks and document all security controls.

Must-have skills

• 2+ years of professional Flutter development experience.
• Strong knowledge of mobile security practices and encryption libraries.
• Proficiency with Dart, Android platform integration, and RESTful APIs.
• Experience using Git, GitHub Actions, and code review tools.
• Ability to write clean, testable code and unit tests with Mockito.

Nice to have

• Familiarity with AWS services, especially KMS and Cognito.
• Exposure to CI/CD security tooling such as Snyk or Trivy.