Pretty feedback for Bash scripts.
Lightweight • Dependency-free • Pleasant by default

Use the functions in this script by sourcing it in your scripts, e.g. source [path_to]/pfb.sh

An example of pretty feedback provided by pfb can be shown by running the following command.

source ./pfb.sh && pfb test

pfb can be configured using environment variables:

Example:

export PFB_SPINNER_STYLE=13
export PFB_DEFAULT_LOG_DIR="/var/log/myscripts"
export NO_COLOR=1  # Disable colors for accessibility
source ./pfb.sh

pfb provides regular log level feedback using the following command.

pfb [info|warn|error|success] message

pfb provides headings with a leading icon and sub-headings for adding detail under the heading.

A heading is echoed by using the following pfb command.

pfb heading message [icon]

Subheadings can be echoed after headings using

pfb subheading message

Not really a heading but a formatted subheading indicating a suggestion...

pfb suggestion message

pfb can provide feedback that a command is being processed using

pfb spinner start message some_command

You can also start a spinner manually and stop it later:

pfb spinner start message
pfb spinner stop

The prefix label defaults to [wait]. Use PFB_SPINNER_LABEL to customise it or set it to empty to suppress the prefix entirely:

PFB_SPINNER_LABEL="deploy" pfb spinner start "Deploying to production..." deploy.sh
# [deploy] ⣾ Deploying to production...

PFB_SPINNER_LABEL="" pfb spinner start "Downloading..." 'curl ...'
# ⣾ Downloading...

This is usefully followed up with a pfb success log level message or a pfb answer message.

For operations with a known completion percentage, use the determinate progress bar:

pfb progress <current> <total> [message]

Each call redraws on the same line. Follow the loop with a log-level message to signal completion:

files=(*.log)
for i in "${!files[@]}"; do
    process "${files[$i]}"
    pfb progress $(( i + 1 )) ${#files[@]} "Processing files..."
done
pfb success "All files processed!"

The bar adapts to the terminal width and respects PFB_SPINNER_LABEL for the prefix (including the empty-string no-prefix option). Colors degrade to ASCII = characters when NO_COLOR is set:

# Color mode (default)
# [wait] ████████████░░░░░░░░░░░░░░░  42% Downloading...

# No-color mode
# [wait] [============               ]  42% Downloading...

Collect text input from the user with an optional default value:

result=$(pfb input "prompt message" [default_value])

Example:

name=$(pfb input "What's your name?" "Anonymous")
echo "Hello, $name!"

The default value is shown in brackets and used if the user presses enter without typing anything.

Ask the user a yes/no question and get the result as an exit code:

pfb confirm "question" [yes|no]

Returns exit code 0 for yes, 1 for no. Use left/right arrow keys, y/n, or enter to select. The selected option is highlighted and the hint capitalises the current default (Y/n or y/N).

An optional second argument sets the default answer (default is yes):

pfb confirm "Delete all files?" no    # Defaults to No
pfb confirm "Continue?" yes           # Defaults to Yes (explicit)

Example:

if pfb confirm "Delete this file?"; then
    rm file.txt
    pfb success "File deleted"
else
    pfb info "Cancelled"
fi

pfb provides a way to select from a list of options using the up/down keys using

pfb select array_of_options

Example:

options=("Option 1" "Option 2" "Option 3")
selected=$(pfb select "${options[@]}")
echo "You selected: ${options[$selected]}"

For integrating with external tools like fzf, use the prompt/answer pattern:

pfb prompt message

The pfb answer message can be used to put a formatted answer after the prompt message.

pfb answer message

This pattern saves the cursor position after the prompt and restores it when displaying the answer, keeping everything on one line. For simple text input, use pfb input instead.

Cursor helper functions and color variables are available immediately after sourcing pfb.sh — no prior pfb call is required.

Note: Color variables (INFO_COLOR, BOLD, RESET, etc.) are set to ANSI codes only when stdout is a TTY at source time. In CI or piped contexts, set PFB_FORCE_COLOR=1 before sourcing pfb.sh to force colors.

pfb uses ANSI/VT100 Terminal Control Escape Sequences which you can use yourself:

Examples of how these area used can be seen in the pfb script.

Examples using these variables:

printf "${BYELLOW}${RED}${BOLD}This is bold red text on a yellow background${RESET}"

echo "${REV}This is reversed text${RESET}"

printf "${INFO_COLOR}Informational message${RESET}\n"

printf "${SUCCESS_COLOR}Success message${RESET}\n"

Examples using RGB color functions:

printf "$(rgb_fg 215 119 87)Orange text${RESET}\n"

printf "$(rgb_bg 50 150 50)Green background${RESET}\n"

printf "$(rgb_fg 255 100 200)$(rgb_bg 50 50 100)Custom colors${RESET}\n"

gum is a more comprehensive TUI toolkit that offers similar functionality with additional components like file browsers, tables, pagers, and advanced text filtering.

When to use pfb:

• Zero dependencies - just source a single bash file (~10KB)
• Maximum portability (works anywhere with bash 4.0+)
• No external binary installation required
• Direct function calls (no process spawning overhead)
• Basic terminal feedback is sufficient for your needs

When to use gum:

• Need advanced components (file browser, tables, fuzzy filtering, pagers)
• Building sophisticated interactive scripts
• Prefer standalone binaries over sourced libraries
• Want extensive styling options via CLI flags

pfb occupies the lightweight, dependency-free niche — ideal for scripts you distribute or run in constrained environments where installing external tools adds friction.