What is storage-engine-selector?

A guide for choosing a database storage engine, the part that organizes data on disk or in memory, using options such as LSM-trees, B-trees, and in-memory storage.

It helps evaluate systems such as RocksDB, InnoDB, and LevelDB, diagnose write amplification, and choose a write-optimized or read-optimized design.

It makes the trade-offs between fast writes, fast reads, memory use, and write amplification easier to compare for a specific workload.

storage-engine-selector — Skill for Claude Code by bookforge-ai

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add bookforge-ai/bookforge-skills --skill storage-engine-selector

Clone the repo

git clone --depth 1 https://github.com/bookforge-ai/bookforge-skills

Made for: Claude Code.

Or install designing-data-intensive-applications, the plugin that ships this one along with the rest of its 14 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/bookforge-ai/bookforge-skills/storage-engine-selector/github.svg)](https://agentmods.dev/skills/bookforge-ai/bookforge-skills/storage-engine-selector)

Your own site

<a href="https://agentmods.dev/skills/bookforge-ai/bookforge-skills/storage-engine-selector"><img src="https://agentmods.dev/badge/skills/bookforge-ai/bookforge-skills/storage-engine-selector/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/bookforge-ai/bookforge-skills/storage-engine-selector"><img src="https://agentmods.dev/badge/skills/bookforge-ai/bookforge-skills/storage-engine-selector.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 216 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 8,258 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin unknown No closer match found in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00216	$0.08258
Opus 5	$0.00108	$0.04129
Sonnet 5	$0.00043	$0.01652
Haiku 4.5	$0.00022	$0.00826

Measured 9d ago against content hash 8a0442647140, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

storage-engine-selector scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

books/designing-data-intensive-applications/skills/storage-engine-selector/SKILL.md · 474 lines

The source is not reproduced here

Licensed CC-BY-SA-4.0

The repository is licensed CC-BY-SA-4.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

Files

What ships with it

3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

9d ago First seen · 474 lines · 216 tokens per session scan A 8a0442647140

Subscribe to this mod's changes

storage-engine-selector is a skill published in the GitHub repository bookforge-ai/bookforge-skills (35 stars, last pushed 4mo ago), licensed CC-BY-SA-4.0. It adds 216 tokens to every session and 8,258 once invoked, about $0.0011 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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storage-engine-selector