This web app runs entirely client-side and is meant as an educational tool for understanding SLI, SLO and error budgets as well as alerting rules based on Google SRE books.
At a previous company, engineering teams selected SLIs and SLOs based on what was easiest to implement and measure. Nobody had devops, SRE, or performance testing experience. Your SLC seems like a really great interactive primer. I imagine a lot of engineering teams need help in this area.
It's a common pitfall to measure what's easy. OTOH, the calculations can be quite arcade and hard to relate to. Many observability platforms have something in place but they leave more to be desired.
Service Levels can be quite simple at a high level but as soon as you start implementing them, the calculations can quickly become abstract and hard to understand.
