As @gitlost had noted in #13 (comment) , the Gettext library that the makepot command uses requires PHP 5.4+, which makes it unfit to be bundled with the current WP-CLI, with its PHP 5.3.29+ requirement.

Our current options:

• Fork the oscarotero/Gettext library, make it PHP 5.3-compatible and submit PR to upstream (which is unlikely to be accepted)
• Fork the oscarotero/Gettext library into our own org and maintain our own PHP 5.3-compatible branch
• Keep the makepot as a separate command for now and rediscuss bundling it with WP-CLI 2.0

@gitlost, @swissspidy thoughts?