The GDPR does not mandate open source. It mandates accountability: lawful basis, purpose limitation, data minimisation, security of processing, subprocessors, transfers, breach notification, and the rights of data subjects. When you migrate workloads to open‑source platforms or self‑hosted stacks, supervisors still ask one question: can you show how controls are implemented and who is responsible?
Requirements that shape a defensible migration
- Article 30 records updated for new processing activities, systems, and retention; no “shadow” databases after cutover.
- Legal basis and transparency aligned with any new analytics, logging, or model training; open tooling does not excuse repurposing data.
- Subprocessor and transfer logic clarified: self‑hosting may reduce certain commercial subprocessors but can introduce colocation, support vendors, or cloud regions—each needs contracts and transfer tools where relevant.
- Security measures (Article 32) evidenced: patching, access control, encryption, segmentation, backup and restore tests—ideally mapped to your risk assessment.
- DPIA triggers re‑evaluated for high‑risk processing (profiling, large‑scale sensitive data, systematic monitoring). AI‑adjacent flows often re‑open this conversation.
Open source helps when it improves inspectability and portability: you can document configurations, retain logs under your policy, and avoid lock‑in that makes erasure or rectification technically impractical. It hurts when teams assume “on‑prem equals compliant” without governance—then you trade vendor opacity for operational gaps.
Does your migration pack include an updated ROPA, transfer analysis, and DPIA decision trail before production traffic moves?