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Abstract digital blueprint depicting interconnected servers, networks, and cloud nodes on a dark navy grid representing Calexi’s precision-engineered, Defence-grade ICT systems integration and design assurance.

ICT Engineering Services for Government and Defence

We design, integrate and deliver secure ICT systems that work in the real world — from blueprint to handover.

Partner with Calexi for high-assurance ICT engineering that stands up to scrutiny and scales with confidence.

At Calexi, our ICT engineering services span the entire solution lifecycle. From requirements capture and architectural design through to delivery, testing and secure handover. We specialise in high-assurance environments, supporting Defence, government, and critical infrastructure clients with trusted engineering capability.

Our engineers work across complex, multi-vendor landscapes to deliver secure, interoperable systems that meet operational, regulatory, and mission needs. Whether you are building a new platform or modernising a legacy environment, we ensure every component is architected for security, performance, and compliance.

From hands-on build and integration through to system validation, documentation, and stakeholder engagement, Calexi brings precision, structure, and momentum to critical ICT programs.

Two engineers collaborating in a secure data centre, reviewing a network architecture blueprint overlaid with holographic diagrams symbolising Calexi’s collaborative, high-assurance ICT engineering approach.

Key Service Features

  • Requirements capture and stakeholder alignment
  • Solution architecture and secure system design
  • Multi-vendor integration and interoperability
  • High-assurance platform build and deployment
  • Rigorous test planning and validation
  • System hardening and ISM alignment
  • Full documentation and operational handover
  • Legacy system transformation and uplift
  • Engineering support for accreditation processes
  • Ongoing lifecycle and sustainment planning

Proven Capability in the Field

  • Digital illustration showing a business handshake symbolizing a seamless Microsoft 365 migration. On the left, dark legacy servers with red warning lights represent outdated, unreliable systems. On the right, a glowing blue cloud with Microsoft 365 app icons (Word, Outlook, Excel) represents the modern, resilient cloud environment. The handshake in the center conveys trust, collaboration, and smooth transition.

    Microsoft 365 Service Migration

    A Defence SME struggling with multi-day outages migrated to Microsoft 365 under Calexi’s leadership. The seamless migration achieved zero downtime, 100% staff adoption, and significant resilience uplift, enabling faster collaboration and growth.

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  • A glowing digital shield with a central padlock symbol, surrounded by eight evenly spaced turquoise-blue nodes connected in a circular pattern. The background features a dark blue gradient with subtle circuit lines, symbolizing cyber security, Essential Eight compliance, and Defence-level protection.

    SME Essential Eight Compliance

    A Defence industry SME required Essential Eight compliance to execute a Defence contract. Calexi delivered a full uplift in just four weeks, achieving ML1 across all areas, ML3 in key controls, and DISP membership within 3 months — reducing risk from very high to low/medium.

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  • A glowing digital shield with a central padlock symbol, surrounded by eight evenly spaced turquoise-blue nodes connected in a circular pattern. The background features a dark blue gradient with subtle circuit lines, symbolizing cyber security, Essential Eight compliance, and Defence-level protection.

    Critical Infrastructure Project Remediation

    A transport critical infrastructure project was at risk due to cascading system failures caused by poor maintenance in a high-security environment. Calexi rapidly stabilised the systems in 2 weeks, reduced the risk profile from very high to medium, recommenced commissioning, and delivered a comprehensive maintenance plan with strong stakeholder confidence.

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Why Calexi

Calexi is an Australian-owned consultancy with security-cleared engineers and a track record of success in Defence and regulated sectors. We understand the demands of delivering critical ICT systems in high-assurance environments, where compliance, clarity, and confidence matter.

Our consultants combine deep technical expertise with structured delivery, from requirements workshops to signed-off solutions. We know how to move from intent to implementation without compromising security, compliance, or business continuity. Whether you’re building from the ground up or recovering a project at risk, Calexi brings the engineering discipline needed to succeed.

Start your next ICT project with clarity and confidence.