Free Makefile test files and sample generator
Tab-indented targets and recipes. Generate valid sample Makefiles for testing build tooling, editors and CI.
What is a .makefile file?
Makefile: GNU Make Build File. A Makefile declares targets and the tab-indented recipes that build them. The tab requirement is genuinely significant, spaces produce an error, which makes it a good test of whether your tooling preserves whitespace exactly.
Why generate a test Makefile file?
- Confirm an editor, upload path or template engine preserves real tab characters.
- Test a build-file parser against many targets.
- Check error reporting on malformed recipes.
How a .makefile file is identified
A .makefile file has no signature at the start. A text format has no identifying leading bytes, so the extension and the reported media type are the only claims about it until a parser actually reads it, which is why validating uploads by extension alone is unsafe.
How the size lands on the exact byte
The format allows comments, so the padding is comment lines, legal, inert, and visible if you open the file.
Negative testing with broken Makefile files
- Invalid. Identifiable, but wrong inside, so it fails during parsing.
- Corrupted. The leading bytes are destroyed. Same length as the valid file.
- Incomplete. Truncated part-way, so it is genuinely shorter.
- Empty. Chosen under Content rather than File Condition: valid structure, no data.
Which failure to reach for, and what to assert for each, is covered in how to make a corrupted file for testing. For upload limits and type checks see testing file upload validation, and for this format's encodings, UTF-16 and BOM test files.
Sample Makefile content
.PHONY: all all: task0 task0: @echo "task 0"
This shows the shape of the file. Your download is generated fresh at the size you choose, so the values will differ.
How to open and verify the file
Run `make -n -f Makefile` for a dry run that parses without executing.
Media type text/plain · extension .makefile · category Config & DevOps
Generate a .makefile file → · questions about sizes, privacy or cost are answered on the site FAQ.
Frequently asked questions about Makefile files
What identifies a .makefile file?
Nothing at the start of the file does. A text format has no identifying leading bytes, so the extension and the reported media type are the only claims about it until a parser actually reads it, which is why validating uploads by extension alone is unsafe.
How can a .makefile file be an exact number of bytes?
The format allows comments, so the padding is comment lines, legal, inert, and visible if you open the file.
Can I download several broken Makefile files at once?
Yes, select more than one File Condition and you get one ZIP containing a .makefile per condition, each named after its condition.
Can the Makefile file use UTF-16 or a byte-order mark?
Yes. .makefile is a text format, so it can be generated as UTF-8, UTF-8 with a byte-order mark, UTF-16 LE or UTF-16 BE. The body is shortened before re-encoding so the finished file still lands on the exact size you asked for. Note that a UTF-16 file always has an even byte count.
How do I open or verify the Makefile file?
Run make -n -f Makefile for a dry run that parses without executing.
Related Config & DevOps formats
ENV · INI · TOML · Dockerfile · gitignore · CONF · Properties · EditorConfig