Location: Remote, Vietnam
Employment Type: Full-time
Schedule: Flexible time
Level: Mid-Senior
Compensation: 40.000.000 - 55.000.000 VND/month
Company: Twin Signal
About Twin Signal
Twin Signal, a ZenitechCS company, is dedicated to launching new products and expanding into new markets, building on our proven foundation of excellence. For more than 15 years, ZenitechCS has delivered reliable IT solutions to clients across California, USA. Through Twin Signal, we’re extending that legacy with focused AI-first innovation and market expansion.
Our capabilities span end-to-end technology services, including IT Service Management, Software Development, Database Administration, Information Security, Business Intelligence, Computer Networking, and Systems Administration.
Work Policy
This position is 100% remote and based in Vietnam. The mid/senior Software Engineer Desktop/Native is expected to be available and responsive during established working hours, with flexibility based on project and operational requirements. Team members must maintain a secure working environment and prevent data exposure through cameras, bystanders, insecure networks, or other risks.
Key Responsibilities
- Design, develop, test, deploy, and maintain lightweight desktop/endpoint agents that run persistently in the background with minimal or no UI footprint
- Implement agent capabilities for IT administration: account creation and lifecycle management, software installation/uninstallation, configuration management, patching, and inventory collection
- Build and maintain networking and access-control features: VPN client integration, ZTNA tunnel establishment, firewall rule enforcement, and network posture checks
- Map software-defined access policies (roles, groups, conditional access rules) to real-world enforcement points across the OS (users, permissions, local groups), Identity providers (SSO/IdP, directory services), network layer (routing, segmentation, firewall), and SaaS applications (API-driven access control)
- Integrate agents with backend policy engines, identity providers, cloud services, and third-party security tools via APIs
- Investigate defects, performance issues, security vulnerabilities, and production incidents affecting agent reliability or policy enforcement accuracy
- Create technical documentation, runbooks, architecture notes, and implementation guides for agent behavior and policy-mapping logic
Primary Responsibilities
- Develop native and cross-platform desktop agents using appropriate low-level and systems languages/frameworks
- Build maintainable agent architectures with clear separation between the local enforcement layer, communication layer, and policy/control-plane interfaces
- Implement secure authentication, authorization, local data protection, secure credential storage, logging, telemetry, and tamper-resistant error handling appropriate for security-sensitive, privileged software
- Design and maintain agent lifecycle features: silent installation, background operation, auto-update, self-healing, crash reporting, uninstall protection, and version compatibility across OS updates
- Optimize agent performance for minimal CPU/memory footprint, fast startup, low battery/network impact, and high reliability across supported platforms
- Implement real-time or near-real-time policy synchronization between the management plane and the local agent, ensuring OS-level, identity-level, and network-level state stays consistent with defined policy
- Integrate with identity providers (e.g., Entra ID/Azure AD, Okta, Google Workspace), network/firewall APIs, VPN/ZTNA gateways, and SaaS admin APIs to enforce and audit access
- Write clean, modular, testable, and well-documented code, with particular care given to code running with elevated/system privileges
- Participate in code reviews, threat modeling, testing, release planning, and production deployments
- Apply secure development practices: least-privilege design, dependency management, supply-chain integrity, code signing, and data-protection requirements
- Communicate progress, risks, dependencies, and technical tradeoffs clearly to project stakeholders
Secondary Responsibilities
- Contribute to standard cybersecurity software application development, including management consoles, policy engines, and backend services that support the agent ecosystem
- Support agent installation, upgrades, migrations, and troubleshooting for customers and internal IT/security teams
- Monitor agent health, telemetry, crash reports, connectivity, and policy-enforcement drift across the fleet
- Conduct root-cause analysis for recurring agent, network, identity-sync, or platform-specific issues
- Contribute to CI/CD pipelines, automated testing, code signing, packaging, and release automation for both agent and server-side components
- Assist with solution estimates, technical discovery, and architecture discussions related to access control mapping
- Maintain development environments and support quality assurance and user acceptance testing
- Mentor junior engineers and contribute to shared engineering practices and technical standards
Required Qualifications
- Strong professional English communication skills, both written and verbal
- 3+ years of professional software engineering experience for mid-level candidates, or 5+ years for senior-level candidates
- Proficiency in at least one relevant systems/native language, such as Rust, Go, or a comparable language
- Hands-on experience building, shipping, and maintaining background services, daemons, system agents, or other privileged/low-footprint desktop software
- Experience with OS-level programming concepts: services/daemons, permissions models, local user/group management, process management, and system APIs on Windows, macOS, and/or Linux
- Solid understanding of networking fundamentals: TCP/IP, DNS, routing, firewalls, VPN protocols, and/or ZTNA concepts
- Working knowledge of identity and access management concepts: authentication (SSO, SAML, OIDC), authorization models (RBAC/ABAC), and directory services
- Experience designing and consuming REST APIs and integrating third-party systems, including identity providers and SaaS platforms
- Familiarity with local data storage, secure credential storage, encryption at rest/in transit, and secrets management
- Experience with Git, code review, automated testing, build tooling, and software release practices
- Ability to independently troubleshoot agent, network, identity-integration, and platform-specific issues
- Excellent analytical, organizational, prioritization, documentation, and collaboration skills
Preferred Qualifications
- Experience building agents/clients for RMM (remote monitoring and management), EDR/XDR, MDM, VPN, or ZTNA products
- Experience developing agents for multiple desktop/server operating systems, including Windows, macOS, and Linux
- Experience with installers, silent deployment, code signing, auto-update systems, and large-scale software distribution
- Experience with JavaScript or Python
- Experience with Rust or Go for systems-level or security-focused development
- Direct experience integrating with identity providers (Entra ID/Azure AD, Okta, Ping, Google Workspace) or SaaS admin/security APIs (e.g., Google Workspace, Microsoft Graph, Slack, Salesforce)
- Familiarity with cloud platforms such as Azure or AWS, and real-time communication protocols (WebSockets, gRPC, MQTT)
- Experience with Docker, CI/CD pipelines, infrastructure-as-code, or deployment automation
- Knowledge of secure software development, threat modeling, encryption, secrets management, and data privacy/compliance practices (e.g., SOC 2, ISO 27001)
- Experience with policy engines, rules evaluation systems, or attribute-based access control implementations
- Experience working in a security product, consulting, or distributed-team environment
- Prior experience mentoring developers or leading small technical initiatives
Success Measures
- Reliable, low-footprint, and secure agent operation across supported platforms
- Accurate, verifiable mapping between defined access policies and real-world enforcement across OS, Identity, Network, and SaaS layers
- Timely, dependable delivery of agent and supporting security software
- Reduced recurring defects, policy-drift incidents, and security issues through effective root-cause analysis
- Clear, complete, and current technical documentation of agent behavior and policy logic
- Effective collaboration with stakeholders and engineering team members
- Measurable improvements in testing, release quality, automation, and engineering maturity
Schedule
The hours are flexible, but the candidate must be able to respond to issues during the following time: Monday to Friday, 8:00 - 17:00 (Vietnam Time).
Compensation
Software Engineer Desktop/Native: 40.000.000 - 55.000.000 VND/month
Important Note: We will not hire a candidate who receives a “low” assessment in English proficiency.
Perks & Benefits
- End of Year Bonus: Standard bonus is valued at least one month’s salary. If the company is successful and staff have performed well, highly performing staff may receive larger bonuses. Vietnamese staff will receive bonuses before Tết.
- Health Insurance: Health insurance will be provided to all staff.
- Dental Insurance: Dental insurance will be provided to all staff.
- Vision Insurance: Vision insurance will be provided to all staff.
- Remote Work: The position is 100% remote.
- Paid Time Off (PTO): We offer a base of 15 days of paid time off in addition to 12 national holidays, for a total of 27 paid days off. Additional time off can be requested as needed.
- Mentorship: We offer on-the-job training, continuing education, code review, and technical assistance when required.