Overall looks good, just a few changes before it can be merged:

On Mon, Jul 27, 2020 at 10:05:56PM -0600, Jesse Gibbons wrote:
> V2 attached.
> 
> On 7/25/20 9:30 AM, Marius Bakke wrote:
> > Jesse Gibbons <jgibbons2357@gmail.com> writes:
> > 
> > > * gnu/packages/piet.scm: New file.
> > > * gnu/local.mk: Add it.
> > The patch seems to have been mangled so it does not apply.
> > 
> > It would be great if you could expand the description with information
> > about what the piet language is and why users would want to try it.

> From 077214a6e13d770f70dfba2a7fe2faf40b1fbc56 Mon Sep 17 00:00:00 2001
> From: Jesse Gibbons <jgibbons2357+guix@gmail.com>
> Date: Mon, 20 Jul 2020 20:35:09 -0600
> Subject: [PATCH v2 1/1] gnu: Add npiet.
> 
> * gnu/packages/piet.scm: New file.
> * gnu/local.mk: Add it.
> ---
>  gnu/local.mk          |  1 +
>  gnu/packages/piet.scm | 60 +++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 61 insertions(+)
>  create mode 100644 gnu/packages/piet.scm
> 
> diff --git a/gnu/local.mk b/gnu/local.mk
> index 7bae1daf61..fc68786ab6 100644
> --- a/gnu/local.mk
> +++ b/gnu/local.mk
> @@ -425,6 +425,7 @@ GNU_SYSTEM_MODULES =				\
>    %D%/packages/photo.scm			\
>    %D%/packages/phabricator.scm 			\
>    %D%/packages/php.scm				\
> +  %D%/packages/piet.scm				\
>    %D%/packages/pkg-config.scm			\
>    %D%/packages/plotutils.scm			\
>    %D%/packages/poedit.scm				\
> diff --git a/gnu/packages/piet.scm b/gnu/packages/piet.scm
> new file mode 100644
> index 0000000000..e82b2aa339
> --- /dev/null
> +++ b/gnu/packages/piet.scm
> @@ -0,0 +1,60 @@
> +;;; GNU Guix --- Functional package management for GNU
> +;;; Copyright © 2020 Jesse Gibbons <jgibbons2357+guix@gmail.com>
> +;;;
> +;;; This file is part of GNU Guix.
> +;;;
> +;;; GNU Guix is free software; you can redistribute it and/or modify it
> +;;; under the terms of the GNU General Public License as published by
> +;;; the Free Software Foundation; either version 3 of the License, or (at
> +;;; your option) any later version.
> +;;;
> +;;; GNU Guix is distributed in the hope that it will be useful, but
> +;;; WITHOUT ANY WARRANTY; without even the implied warranty of
> +;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> +;;; GNU General Public License for more details.
> +;;;
> +;;; You should have received a copy of the GNU General Public License
> +;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
> +
> +(define-module (gnu packages piet)
> +  #:use-module (guix packages)
> +  #:use-module (guix  download)
> +  #:use-module (guix build-system gnu)
> +  #:use-module (gnu packages gd)
> +  #:use-module (gnu packages groff)
> +  #:use-module (guix licenses))
> +
> +
> +(define-public npiet
> +  (package
> +    (name "npiet")
> +    (version "1.3e")

It seems 1.3f has come out in the meantime, can you update to the newer
version?

> +    (source (origin
> +              (method url-fetch)
> +              (uri
> +               (string-append
> +                "https://www.bertnase.de/npiet/npiet-"
> +                version ".tar.gz"))
> +              (sha256
> +               (base32
> +                "1i9ihbjmravid3h7wvns712axdl5xn398hk12pvzl79fs5kcf6g8"))))
> +    (build-system gnu-build-system)
> +    (inputs
> +     `(("gd" ,gd)))

Looking at the build output and the test output (and npiet --help) it
looks like it's missing giflib and libpng.

> +    (native-inputs `(("groff" ,groff)))
> +    (synopsis "Piet interpreter")
> +    (description
> +     "Npiet is an interpreter for the piet programming language.  Instead of
> +text, piet programs are pictures.  Commands are determined based on changes in
> +color.
> +
> +This package includes:
> +@enumerate
> +@item npiet, a piet interpreter with debugging capabilities
> +@item npiet-foogol, a program that builds a piet program from foogol, an
> +algol-like language
> +@item npietedit, an editor for the piet programming language
> +@end enumerate")
> +    (home-page "https://www.bertnase.de/npiet/")
> +    (license gpl2+)))
> +
> -- 
> 2.27.0
> 

Also, when running npietedit, the program complains about missing wish.
npietedit should be wrapped with tk, which provides the 'wish' binary.

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Efraim Flashner   <efraim@flashner.co.il>   אפרים פלשנר
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