I'ma lead out with: no. There are no foss/alt/wrappers to utilize SC. Notably, they have been boss mode in thwarting any attempts at creating such tools in the past.
You (and most who might read here) have very likely already done so -- but it bears mentioning that one should at least perform a cursory "once-over" of SETTINGS upon installation of any app. You should pore over them, tbqh. Snapchat is a prime example.
Something, something...their corporate hedonism hath no bounds...something, something...their app is a known harvester of human (many youth) thoughts and emotions....
But not unlike M$ OS, at least we have options! So, so many options and almost never the good ones by default. Imagine.
Notably, you can and should set up the various levels of trust within your contacts. The app's specific nomenclature escapes me atm, but certain contacts can see certain things and boundries be great, y'all. Turn off auto-anything...Auto Stories(?): off. The other usual suspects are allowed by default: location sharing/updates, logs, histories, etc.
Fair warning: Snapchat practice in voodoo the dark art of dark patterns.......and voodoo. Be vigilant, brothers and sisters.