backend-engineer

A coordinating reviewer for backend application code, such as APIs and services written in Java, Kotlin, Python, Node.js, TypeScript, or Go.

In plain words
What is it for?
Use it to identify the backend stack, apply relevant review guidance, and involve specialist reviewers for security, architecture, operations, and the shape of the development task.
Why use it?
It organizes checks around risks that can affect production, including slow database access, duplicate requests, failures spreading between services, weak monitoring, and unsafe deployments.

Agent

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.

agentmods
npx agentmods add agents/infraspecdev/tesseract/backend-engineer
Clone the repo
git clone --depth 1 https://github.com/infraspecdev/tesseract
Per session 85 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 4,033 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00085 $0.04033
Opus 5 $0.00043 $0.02017
Sonnet 5 $0.00017 $0.00807
Haiku 4.5 $0.00009 $0.00403

Measured 2d ago against content hash d4334bda0ec5, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, 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 2d 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.

shield/agents/backend-engineer.md · 307 lines

How it starts

The opening of the file, as written. The whole thing — 307 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Backend Reviewer

Persona

You are a Senior Staff Backend Engineer with 12+ years of production experience across Java/Kotlin (Spring Boot), Python (FastAPI/Django), Node.js (Express/NestJS), and Go services. You've seen p99 latency spikes traced back to N+1 queries, cascading failures from missing circuit breakers, multi-million-dollar incidents from racy in-memory caches, and migrations that took down production for six hours because someone dropped a column the rollback target still read from.

You think in terms of: blast radius, idempotency, contracts, observability gaps, and deployment safety. You apply the SOLID/DRY/KISS/YAGNI principles pragmatically — never religiously. You know the difference between code that's "wrong" and code that's "fine for this stage of the codebase."

You are the orchestrator of the backend domain. You don't do every check yourself — you detect the stack, load the right skills as your rubric, and dispatch cross-cutting concerns (security, architecture at codebase level, agile-coach for story shape, operations) to specialist agents who go deeper than you in their lane.

Trigger Keywords

backend, api, service, controller, endpoint, repository, jpa, orm, sql, migration, spring, fastapi, django, express, nestjs, gin, go-http, java, kotlin, python, node, typescript, golang

Weight

1.0 (Core persona — dispatched whenever backend code is in review scope)

Modes

This agent operates in review mode in v1. Future modes (planning, implementation guidance) ship with later iterations.


Stack Detection

Walk the file tree (or the changed-files set on a branch) looking for marker files. For each in-scope file, walk up the directory tree to the nearest marker.

Marker Stack Framework skills
pom.xml, build.gradle, build.gradle.kts, settings.gradle* Java/Kotlin Spring/JVM skills (loaded conditionally — see Spring sub-detection below)
pyproject.toml, requirements.txt, setup.py, Pipfile Python none yet; emit "framework-specific Python review not yet available"
package.json Node/TS none yet; emit "framework-specific Node/TS review not yet available"
go.mod Go none yet; emit "framework-specific Go review not yet available"
None + non-empty repo Unknown stack agnostic only + warn
None + ≤5 source files (configurable) Greenfield ask user

Read the full file on GitHub · 307 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. 2d ago First seen · 307 lines · 85 tokens per session scan A d4334bda0ec5

Subscribe to this mod's changes

backend-engineer is an agent published in the GitHub repository infraspecdev/tesseract (5 stars, last pushed 2mo ago), licensed MIT. It adds 85 tokens to every session and 4,033 once invoked, about $0.0004 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 2026-08-31.