Many terminal emulators can be configured so that the ANSI bold/bright modifier affects the font face only and not color. In these cases, the ANSI code 1;30 results in the same color as background (assuming default dark background color). This means that things like null values in the jq colorized output are not visible.

It would be great to avoid colors 0 (black) and 7 (white) for colorized output to prevent clashing with potential background colors. Even better would be to allow colors to be configurable for jq (similar to ls colors being configured by an environment variable LS_COLORS).