Smart Storage Decisions in OutSystems: Internal vs External Options
Recently, a logistics customer’s CTO faced a familiar challenge we see across industries—managing growing volumes of unstructured file data within legacy systems. Their legacy audit system, not originally designed to handle massive volumes of unstructured file data (10TB+), struggled with performance due to heavy BLOB storage in a traditional SQL setup. Performance had significantly degraded under the weight of legacy design. A move to OutSystems was on the table to modernize and scale.

At Headfitted, we’re asked this question often. Here’s a practical breakdown for any technical decision-maker navigating OutSystems deployments involving heavy file or streaming data.
1. Storage Cost: Scale Smart
🧩 Internal
OutSystems pricing scales with platform usage and storage. For large or growing file datasets, external storage can help optimize costs while keeping app performance high.
☁️ External (e.g., AWS S3, Azure Blob)
Cloud storage offers tiered, usage-based pricing (hot, cool, archive). Ideal for growing datasets or infrequently accessed data like logs or historical media.
2. Performance: Designed Intent Matters
🧩 Internal
OutSystems databases are optimized for structured data and transactional use cases. For large files or streaming content, cloud storage solutions are a more natural fit.
☁️ External
Cloud storage systems are built for large, unstructured content. Offloading BLOBs here preserves app responsiveness and reduces DB load.
3. Infrastructure: Who Owns the Complexity?
🧩 Internal
Managing large volumes of BLOBs internally often adds storage and monitoring overhead, regardless of the hosting model. Planning for external file handling can reduce that complexity.
☁️ External
Cloud storage is elastic and hands-off. No disk space planning. No hardware upgrades. Just pay for what you use.
4. BI and Analytics: Can You Get to the Data?
🧩 Internal
OutSystems requires APIs or ETL layers to connect to BI tools. While this works well in many scenarios, cloud storage often simplifies direct BI access.
☁️ External
Cloud storage integrates easily with Power BI, Tableau, and BigQuery. Built-in connectors simplify access to insights.
5. Trade-offs of Using External Storage
- Integration Overhead: Connecting OutSystems to external storage requires effort—REST APIs, error handling, and secure transfers.
- Data Consistency: Syncing metadata in OutSystems with files in S3/Blob demands robust transactional integrity design.
6. Decision Framework for Technical Leaders
Ask these questions:
- What’s your data growth curve? If you expect volume, internal won’t scale.
- How often is data accessed? Infrequent use favors cold storage tiers.
- Is low-latency access critical? Then local storage may still be relevant.
- Are you pushing data to BI tools? External makes it easier and faster.
- Do you have compliance constraints? Cloud providers often simplify this.
7. Recommendation: Go Hybrid
The most practical and scalable approach?
- Store metadata and references in OutSystems
- Store BLOBs and files in cloud storage (S3, Azure Blob, etc.)
OutSystems is designed to handle business logic, workflows, and user experience—not heavy file storage. Offloading large content to cloud storage lets each system do what it does best.
📩 Need to architect this right? Let’s talk. We help enterprise teams build scalable, high-performance systems on OutSystems—with the right data strategy.



