Everyone loves https://canary.tools and I wholeheartedly recommend that you take a look (and adopt the free tokens if nothing else); but there is another amazing free+awesome toolkit that most companies would benefit from without a privacy audit requirement: https://healthchecks.io - they do exactly what they say, really well, and are both cost-conscious and nerd-savvy. This is almost the opposite of a canary - it reports things that didn't fire - you can find all kinds of creative ways to make this security relevant while staying super inexpensive.