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.
npx skills add selvarajmurugesan90/ops-engineering-skills --skill database-schema-migration-with-liquibase-and-flywaygit clone --depth 1 https://github.com/selvarajmurugesan90/ops-engineering-skillsWrote 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.
[](https://agentmods.dev/skills/selvarajmurugesan90/ops-engineering-skills/database-schema-migration-with-liquibase-and-flyway)<a href="https://agentmods.dev/skills/selvarajmurugesan90/ops-engineering-skills/database-schema-migration-with-liquibase-and-flyway"><img src="https://agentmods.dev/badge/skills/selvarajmurugesan90/ops-engineering-skills/database-schema-migration-with-liquibase-and-flyway/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.
<a href="https://agentmods.dev/skills/selvarajmurugesan90/ops-engineering-skills/database-schema-migration-with-liquibase-and-flyway"><img src="https://agentmods.dev/badge/skills/selvarajmurugesan90/ops-engineering-skills/database-schema-migration-with-liquibase-and-flyway.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium MCP Rug Pull · line 154 Docker image references without a specific tag (:latest is implicit) or digest (@sha256:...) can be silently replaced by a malicious image.Fix: Pin the image: image:tag or image@sha256:abc123
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 | $0.00124 | $0.04499 |
| Opus 5 | $0.00062 | $0.02250 |
| Sonnet 5 | $0.00025 | $0.00900 |
| Haiku 4.5 | $0.00012 | $0.00450 |
Grade A, and why
database-schema-migration-with-liquibase-and-flyway 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 12d 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.
How it starts
The opening of the file, as written. The whole thing — 388 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Database Schema Migration with Liquibase and Flyway
Purpose
Schema migrations are the one place where "it worked in my local database" and "it's safe to run against production" are routinely two very different claims — a migration that runs cleanly against an empty or small test database can lock a large production table for minutes, and a migration applied without considering the currently-running (old-version) application code can break it mid-rollout. This skill covers the two dominant version-controlled migration tools — Liquibase (XML/YAML/SQL changesets tracked in a changelog, with built-in rollback support) and Flyway (plain versioned SQL/Java migrations, forward-only by convention) — the forward-only-vs- reversible design decision itself, backward-compatible migration patterns for zero-downtime rolling deploys, and testing migrations in CI before they ever reach a real environment. It complements the database-specific operational skills in this repo (postgresql-operations-and-performance-tuning, mongodb-operations-and-scaling) by covering the tooling and process layer that should sit in front of any hand-run DDL change against those systems.
When to use
- Introducing version-controlled migration tooling (Liquibase or Flyway) to a project that currently applies schema changes by hand or via untracked scripts.
- Writing a new migration and deciding whether it needs (or can have) a rollback, and if forward-only, what the recovery plan is instead.
- A migration failed partway through and left the schema (and the tool's tracking table) in an inconsistent state.
- Designing a schema change (column rename, type change, NOT NULL addition, table split) that must not break the currently-running application during a rolling deploy where old and new code run simultaneously.
- Setting up CI to actually run migrations against a real (or realistic) database before merge, rather than only reviewing the SQL by eye.
- Migrating from one tool to another, or reconciling a migration history that's drifted from actual schema state.
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.
- 12d ago First seen · 388 lines · 124 tokens per session scan A 1decb0deb8d5
database-schema-migration-with-liquibase-and-flyway is a skill published in the GitHub repository selvarajmurugesan90/ops-engineering-skills (39 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 124 tokens to every session and 4,499 once invoked, about $0.0006 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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