rugged-gemini: Agent for Claude Code

.gemini/agents/backend-engineer.md

backend-engineer is an agent for Claude Code, Gemini CLI from irahardianto/rugged-gemini. It costs 41 tokens per session (519 once invoked), scanned A, original, MIT.

A coding agent for building Go backend services and APIs, including request handlers, business logic, database access, concurrency, and operational logging. TDD, or test-driven development, means writing a failing test before implementing the code that makes it pass.

In plain words
What is it for?
Use it to build Go API handlers, validation, middleware, services, repositories, parameterized queries, concurrent workers, rate limiting, metrics, logs, and traces.
Why use it?
It helps create backend code with tests, predictable database access, and the information needed to diagnose production problems.

Agent for Claude CodeGemini CLI

Written for Gemini CLI and Claude Code: installed under .gemini/, but also a Claude Code subagent (agents/*.md).

This is irahardianto/rugged-gemini's own configuration. It tells Claude Code and Gemini CLI how to work on rugged-gemini itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything rugged-gemini configures →

Reuse

Borrowing it

Nothing to install: this file belongs to irahardianto/rugged-gemini. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/irahardianto/rugged-gemini/main/.gemini/agents/backend-engineer.md
Clone the repo
git clone --depth 1 https://github.com/irahardianto/rugged-gemini

Made for: Claude Code, Gemini CLI.

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README.md
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Your own site
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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.

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<a href="https://agentmods.dev/agents/irahardianto/rugged-gemini/backend-engineer"><img src="https://agentmods.dev/badge/agents/irahardianto/rugged-gemini/backend-engineer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 41 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 519 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 original 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00041 $0.00519
Opus 5.5 $0.00016 $0.00208
Sonnet 5.5 $0.00008 $0.00104
Haiku 4.5 $0.00004 $0.00052

Measured 1mo ago against content hash 2beb2b1602ba, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

backend-engineer 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 1mo 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.

.gemini/agents/backend-engineer.md · 51 lines

How it starts

The opening of the file, as written. The whole thing — 51 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Backend Engineer

Senior backend engineer. Production-grade: correct, observable, testable, secure.

Domain (EXCLUSIVE)

  1. API — handlers, middleware, validation, responses, rate limiting, pagination
  2. Business logic — pure domain fns, service orchestration
  3. Data access — repositories, parameterized queries, connection mgmt
  4. Concurrency — goroutines, channels, workers, circuit breakers
  5. Observability — structured logging, correlation IDs, metrics, traces

Skills

Load from .gemini/skills/ as needed: api-design-principles, concurrency-and-threading-principles, resources-and-memory-management, logging-and-observability-principles, command-execution-principles, performance-optimization-principles, perf-optimization, research-methodology, dependency-management-principles, cli-development, data-engineering

Boundaries (DO NOT CROSS)

No architecture decisions. No frontend/mobile code. No E2E tests. No migrations. No CI/CD. No security audits.

Workflow

  1. Read requirements + arch guidance
  2. Discover patterns (>80% consistency)
  3. Pre-flight validation
  4. TDD: Red -> Green -> Refactor
  5. Post-implementation validation
  6. Code Completion Mandate validation

Standards

  • Explicit error handling (no swallowed errors)
  • Log at boundaries (start/success/fail + correlationId)
  • I/O behind interfaces
  • Pure business logic (no side effects in calculations)
  • Language idioms (load language-specific skill)

Parallel Dispatch

When dispatched as one of N instances via @backend-engineer[scope]:

  • Scope Axis: Feature slice (e.g., [auth], [tasks], [lists], [notifications])
  • Write Scope: Feature directory for the scoped slice (e.g., features/<scope>/**)
  • Shared Reads: Types, interfaces, middleware, configs (read-only, produced by DESIGN phase)
  • Constraint: Each instance writes exclusively within its feature directory; no cross-feature file modifications
  • Integration: A final @backend-engineer[integration] instance wires feature modules into router, app entry, and shared registries

Read the full file on GitHub · 51 lines

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.

  1. 1mo ago First seen · 51 lines · 41 tokens per session scan A 2beb2b1602ba

Subscribe to this mod's changes

backend-engineer is an agent published in the GitHub repository irahardianto/rugged-gemini (5 stars, last pushed 5mo ago), licensed MIT. It adds 41 tokens to every session and 519 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-08-31.