> +(define-public termbox-truecolor
> +  (package
> +    (name "termbox-truecolor")
> +    (version "2019.01.06-c3afbfd")

Could you include a revision number here too?  (See "Version Numbers"
in the manual)

> +    (source (origin
> +              (method git-fetch)
> +              (uri (git-reference
> +                    (url "https://github.com/amirouche/termbox-truecolor.git")
> +                    (commit "c3afbfd8f31cce70ffb8c4ddd153489d9e363780")))
> +              (file-name (git-file-name name version))
> +              (sha256
> +               (base32
> +                "179py858dhhxkj6la84b224r2fjwavygf4daw4dgl3gvv8i07ryj"))))
> +    (build-system waf-build-system)
> +    (arguments
> +     `(#:tests? #f))
> +    (synopsis "Library for writing text-based user interfaces (with true-color support)")

Maybe: "Text-based user interface library"

The true-color support can be mentioned in the description.

> +    (description "Termbox is a library that provides minimalistic API which

"...provides a minimalistic ..."
             ^

> +allows the programmer to write text-based user interfaces.
> +
> +It is based on a simple abstraction: viewing terminals as a table of

I think the paragraph break isn't necessary here.

> +fixed-size cells and input being a stream of structured messages.  Copy &
> +pasting and wide characters (mostly Chinese, Japanese, Korean (CJK)
> +characters) are not really supported.")
> +    (home-page "https://github.com/amirouche/termbox-truecolor/tree/truecolor")
> +    (license license:expat)))

Otherwise looks good to me,

`~Eric