neskit is a homebrew game development kit for NES/FC. It contains a framework library nk, a python-based assembler nkasm, and a set of useful graphics conversion tools and examples. neskit integrates FamiTone2 for music and sound effects.

NOTE: All parts of neskit are work-in-progress and should be considered beta.

With netkit, you write games with 6502 assembly. The nkasm assembler builds .nes ROM files directly, offering syntax similar to ca65. Please refer to files in each of neskit subdirectories.

Thank you for your interest in neskit and NES/FC homebrew in general.


nkasm and the graphics conversion tools are python 2.7 programs. You need python and PIL (Python Imaging Library) to use them. The graphics conversion tools use PIL for reading image files.

Setup for Windows and OS X:

  1. (This step is for Windows only) Install python 2.7
  2. Install pip
  3. Install Pillow
    • Run on command prompt: python -m pip install Pillow

Setup for Linux:

  • Use the package manager to install python and Pillow.

NOTE: FamiTone2 tools only come as .exe binary and source code. You can use Wine to run the .exe on Linux or OS X, or alternatively you can build the tools from source (see tools/famitone2/src/ directory).

Copyright 2013,2014 Valtteri "tsone" Heikkilä

Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved. This file is offered as-is, without any warranty.