makefile

A guide to GNU Make, a tool that runs named build and automation tasks from a Makefile. A Makefile describes targets, their prerequisites, and the commands needed to produce them.

In plain words
What is it for?
Use it to create or maintain Makefiles, define build and test targets, manage variables, run tasks in parallel, and write reusable build rules.
Why use it?
It helps keep build, test, cleanup, and other project commands repeatable. It also explains details that commonly cause errors, such as variable expansion and the required tab before recipe commands.

Skill for Claude CodeCodex

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 skills/itechmeat/llm-code/makefile
Any agent
npx skills add itechmeat/llm-code --skill makefile
Clone the repo
git clone --depth 1 https://github.com/itechmeat/llm-code

Made for: Claude Code, Codex.

Per session 47 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,791 The whole file, excluding the scripts and references it only reads on demand.
Security scan C 1 finding. 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 $0.00047 $0.01791
Opus 5 $0.00023 $0.00896
Sonnet 5 $0.00009 $0.00358
Haiku 4.5 $0.00005 $0.00179

Measured 2d ago against content hash 2231bbf9b4d9, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade C, and why

makefile scanned grade C with 1 finding 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.

Recursive force deletehighDestructive command

rm -rf with a variable or a broad path is one typo away from removing the wrong tree.

rm -rf build/
skills/makefile/SKILL.md · 324 lines

How it starts

The opening of the file, as written. The whole thing — 324 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Makefile Skill

Guidance for creating and maintaining GNU Make build automation.

Quick Navigation

Topic Reference
Rules, prerequisites, targets syntax.md
Variable types and assignment variables.md
Built-in functions functions.md
Special and phony targets targets.md
Recipe execution, parallel recipes.md
Implicit and pattern rules implicit.md
Common practical patterns patterns.md

Core Concepts

Rule Structure

target: prerequisites
        recipe

Critical: Recipe lines MUST start with TAB character.

File vs Phony Targets

# File target - creates/updates a file
build/app.o: src/app.c
        $(CC) -c $< -o $@

# Phony target - action, not a file
.PHONY: clean test install

clean:
        rm -rf build/

Variable Assignment

Operator Name When Expanded
:= Simple Once, at definition
?= Conditional If not already set
= Recursive Each use (late binding)
+= Append Adds to existing value
CC := gcc              # Immediate
CFLAGS ?= -O2          # Default, overridable
DEBUG = $(VERBOSE)     # Late binding
CFLAGS += -Wall        # Append

Automatic Variables

Variable Meaning
$@ Target
$< First prerequisite
$^ All prerequisites (unique)
$? Prerequisites newer than target
$* Stem in pattern rules

Read the full file on GitHub · 324 lines

Files

What ships with it

7 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.

  1. 2d ago First seen · 324 lines · 47 tokens per session scan C 2231bbf9b4d9

Subscribe to this mod's changes

makefile is a skill published in the GitHub repository itechmeat/llm-code (22 stars, last pushed 1mo ago), licensed MIT. It adds 47 tokens to every session and 1,791 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it C with 1 finding (recursive force delete). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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