Infrastructure security architect

Keystone Solutions; Brussel Hoofdstad; Hybrid; EUR 90,000 - 130,000; Full time

Job summary

Keystone Solutions seeks an Infrastructure, Security and Architecture allrounder to guide IT migration from Belgium to the French headquarters. You will audit the Belgian IT landscape, map to HQ standards, define the target architecture and build a phased migration plan across infrastructure, security and governance domains.

Role involves on-site or hybrid work with Belgian and French entities, coordinating with management and external partners to ensure GDPR/ISO 27001 alignment and a smooth

Qualifications

• French and English mandatory.
• Able to speak with stakeholders from teams to C level.
• Comfortable operating in Keystone Solutions' consultancy model, embedded on site or in hybrid mode with the client across Belgian and French entities.

Responsibilities

• Assess Belgian IT landscape and map to French HQ standards.
• Define target architecture and migration approach per domain (rehost, replatform, consolidate, retire).
• Build migration roadmap with phases, milestones, cutovers and rollback plans.
• Prepare business case including costs, risks and expected savings.
• Coordinate with Belgian and French stakeholders; manage vendors and MSPs.
• Ensure security, compliance and governance during the transition.

Skills

French & English

Stakeholder communication

Bilingual leadership

Job description

Mission Overview:

Keystone Solutions is seeking an Infrastructure, Security and Architecture allrounder for a consultancy mission with our client, guiding the migration of IT from a Belgian entity to the French headquarters.

Key Responsibilities:

Assessment & migration strategy

• Audit the Belgian IT landscape: infrastructure, applications, identities, licences, contracts, data flows and technical debt.
• Map Belgian systems against French headquarters standards and identify gaps, overlaps and dependencies.
• Define the target architecture and migration approach for each domain (rehost, replatform, consolidate, retire).
• Build the migration roadmap with phases, milestones, cutover windows and rollback plans.
• Prepare the business case, including costs, risks, licence consolidation and expected savings.

Infrastructure & cloud

• Plan and run the migration of servers, storage, virtualization and backup to the headquarters' datacenter or cloud platforms.
• Lead network integration: WAN/SD-WAN interconnection, VPN, DNS, IP addressing, firewalls and site connectivity.
• Run identity consolidation: Active Directory/Entra ID merger and Microsoft 365 tenant-to-tenant migration (mail, Teams, SharePoint, OneDrive).
• Migrate endpoints and device management (Intune/SCCM, MDM) to headquarters tooling with minimal user disruption.
• Make sure monitoring, backup, disaster recovery and business continuity remain covered throughout the transition.

Security & compliance

• Align the Belgian entity with the group's security policies, ISO 27001 controls and security tooling (EDR, SIEM/SOC, IAM, PAM, MFA).
• Run risk assessments before and after each migration wave, and keep the risk register up to date.
• Keep GDPR compliance in place during data transfers, and update records of processing, DPAs and retention rules.
• Handle NIS2 obligations in both jurisdictions, coordinating with the Belgian CCB and the French ANSSI frameworks where relevant.
• Secure the transition period: temporary trust relationships, privileged access, data-in-transit protection and decommissioning of legacy access.
• Make sure Belgian legacy systems are securely wiped and decommissioned, with evidence kept for audit.

Architecture & governance

• Act as design authority for all technical decisions in the integration programme.
• Document as-is and to-be architectures, standards and integration patterns.
• Rationalize the application portfolio and define the future of Belgium-specific tools (HR, payroll, invoicing, local regulatory systems).
• Make sure Belgian legal and operational requirements are preserved in the target solution, such as social secretariat interfaces, local tax and e-invoicing, and language needs (FR/NL).

Stakeholders & vendors

• Act as the main technical link between Belgian management, French headquarters IT, and external partners.
• Manage vendors, integrators and MSPs: contract transitions, termination notices, TSAs and handover of services.
• Report progress, risks and decisions to steering committees.
• Support change management with user communication, training, hypercare after cutover, and service desk alignment.

Knowledge transfer & handover

• Make sure local IT knowledge is documented and transferred to headquarters teams.
• Define the post-migration support model and operational runbooks.
• Hand over to run teams once each workstream is stable, and close the programme with a lessons-learned review.

Required Qualifications and Skills:

• French and English mandatory.
• Able to speak with all stakeholders from teams to C level.
• Comfortable operating under Keystone Solutions' consultancy model, embedded on site or in hybrid mode with the client across Belgian and French entities.

Consultancy Nature of Work:

• Operate as a Keystone Solutions consultant embedded with the client, coordinating efforts across application, infrastructure and security domains to ensure a smooth migration.
• Work on site with client teams when required, collaborating closely with Belgian and French stakeholders to align timelines, risks and change plans.

Dynamic Projects Across Clients:

• Engage in a flagship migration program while building experience that translates to future client engagements, from infrastructure modernization to application lifecycle optimization.
• Leverage exposure to diverse environments, tools and governance models, strengthening your adaptability and problem solving capabilities.

Turbo-Charged Learning and Development:

• Benefit from Keystone Solutions' coaching culture, peer communities and targeted trainings around networking, application platforms, security, automation and architecture practices.
• Access hands‑on knowledge sharing across consultants to accelerate mastery of containerization, SDLC governance and network delivery topics including F5.

Ambition Skyrocketing within a Consultancy Framework:

• Grow your career through varied client engagements that expand your leadership footprint, from technical coordination to stakeholder management at C level.
• Earn recognition by delivering measurable outcomes in complex cross country transformations, building a track record that unlocks senior consultancy paths.

Keystone Solutions Values in a Consultancy Context:

• Client centricity, craftsmanship, integrity and teamwork guide every mission. Being a K-Stone means you bring these values to each client project, consistently aligning decisions with impact and trust.
• We champion clarity and accountability, ensuring every engagement is delivered with transparent communication and quality execution.

Role-Specific Consultant Advantages:

• Apply your infrastructure, security and architecture expertise across multiple client scenarios, from data center and network transitions to application platform readiness and SDLC maturity.
• Strengthen bilingual leadership by facilitating workshops, steering committees and operational ceremonies in both French and English.