Storage & Layout

What this competency is

Choosing storage systems and physical layout strategies that balance cost, performance, and correctness for expected access patterns.

Why it matters

Storage decisions shape query performance, operational complexity, and cost envelopes for years.

What to evaluate in agents

• Fit between workload and storage engine characteristics.
• Partitioning, clustering, indexing, and file format strategy.
• Retention, tiering, and lifecycle management decisions.
• Trade-offs between latency, throughput, and storage cost.

Strong signals

• Ties storage choices to concrete read/write access patterns.
• Explains partitioning and compaction implications.
• Uses appropriate formats and indexing for target workloads.
• Includes retention and data lifecycle policy.

Weak signals

• Recommends storage technologies by popularity alone.
• Ignores small-file, skew, or hotspot risks.
• Omits lifecycle controls and retention boundaries.
• Treats all workloads as if they need the same latency profile.

Example evaluation prompts

• "Design table layout for high-volume append events with frequent time-range queries."
• "Choose a storage strategy for cold historical data and near-real-time dashboards."

Related competencies

• Scalability and Performance Engineering
• Distributed Systems and Consistency
• Technology Selection and Architecture Tradeoffs