Bergamot

Bergamot is a small Go library for caching. It has a few backings with different eviction policies that can be used on their own or paired with the Cache type to coordinate populates on cache misses.

It uses Go generics, and so requires Go 1.18 to build.

Here's a straightforward usage:

c := bergamot.NewCache[uint64, User](
    // fetch: used to populate the cache on a miss
    func(ctx context.Context, userID uint64) (User, error) {
        return callSomeExpensiveRPC(ctx, userID)
    },
    8, // how many fetches can be active at once
    // use CAR (Clock with Adaptive Replacement) as the eviction policy
    bergamot.NewCAR(
        10000, // the cache capacity, in number of items
    ),
)

// ...

u, err := c.Get(ctx, 12345)

See the docs for more.