# Fergius-Engineering > Open-source publisher. Listings imported from github.com/Fergius-Engineering — credited to the original author with their license. - **Listings:** 20 - **Total installs:** 0 - **Profile:** https://agentstack.voostack.com/s/fergius-engineering - **Website:** https://github.com/Fergius-Engineering ## Published listings - [Entry Point Audit](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-entry-point-audit) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-entry-point-audit` Use when adding any cross-cutting change - a new gate, limit, permission check, or rule that must apply everywhere. - [Performance At Scale](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-performance-at-scale) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-performance-at-scale` Use when writing code that runs per item, per frame, or per event, or building a cache or lookup over a collection that can grow large. - [Fix The Root Cause](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-fix-the-root-cause) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-fix-the-root-cause` Use when fixing any bug, especially one that surfaces far from where the bad state was created. - [Feasibility Guard](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-feasibility-guard) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-feasibility-guard` Use when about to build or agree to build a feature, test, or check, especially when the request sounds big or clever. - [Opportunistic Fixes](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-opportunistic-fixes) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-opportunistic-fixes` Use when noticing an incidental correctness problem - a stale comment, a wrong doc line, a drifted reference - in the area already being edited. - [Build Release Mindset](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-build-release-mindset) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-build-release-mindset` Use when touching build scripts, release or packaging steps, publish flows, or CI config. - [Verify Against Code](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-verify-against-code) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-verify-against-code` Use when about to assert any factual claim about what code or a product does - in an answer, a doc, a commit message, or anything a user will see. - [Ux Designer Mindset](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-ux-designer-mindset) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-ux-designer-mindset` Use when building or changing anything a user interacts with - a control, a screen, a flow. - [Using Instincts](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-using-instincts) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-using-instincts` Use when doing any work in a project that has the instincts plugin installed - [No Duplicate Logic](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-no-duplicate-logic) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-no-duplicate-logic` Use when adding a case, check, or branch to a function that already exists, especially after jumping straight to the insertion point. - [Tests With Teeth](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-tests-with-teeth) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-tests-with-teeth` Use when writing or reviewing any test, or when about to accept "tests pass" as evidence. - [Plan With Teeth](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-plan-with-teeth) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-plan-with-teeth` Use when about to write an implementation plan, scope a multi-step change, or enter plan mode - before any plan text exists. Also fires when reviewing a plan that states what code does without evidence behind it. - [Question The Premise](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-question-the-premise) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-question-the-premise` Use when several well-reasoned fixes on the same hypothesis have all failed, or when a symptom looks impossible. - [Project Onto All Systems](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-project-onto-all-systems) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-project-onto-all-systems` Use when adding or changing a feature, a data model, or any action that creates, edits, or removes state. - [Fix In The Shared Layer](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-fix-in-the-shared-layer) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-fix-in-the-shared-layer` Use when a bug surfaces while building on one's own shared code - a library, base class, SDK, or component. - [Logging For Remote Diagnosis](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-logging-for-remote-diagnosis) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-logging-for-remote-diagnosis` Use when building any mechanic that could fail on a machine out of reach - a shipped product, a CLI a user runs, a server. - [Independent Review Gate](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-independent-review-gate) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-independent-review-gate` Use when about to call complex or shippable work done, or before merging. - [User Action Edge Cases](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-user-action-edge-cases) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-user-action-edge-cases` Use when finishing anything that depends on external state a person controls - a file, a record, a folder. - [De Ai Prose](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-de-ai-prose) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-de-ai-prose` Use when about to show any prose a human will read - docs, README, commit bodies, UI copy, store text. - [Critical Thinking](https://agentstack.voostack.com/l/skill-fergius-engineering-instincts-critical-thinking) — Skill · Free · security-reviewed — `agentstack add skill-fergius-engineering-instincts-critical-thinking` Use when about to build something someone proposed, especially when the proposer sounds confident and the idea sounds obviously fine. --- Seller on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Install any with `agentstack add `.