database sharding manual vs managed services

hey everyone im wrestling with a common scaling problem for a growing application we're hitting the limits of a single database instance and need to consider sharding ive been looking at implementing manual sharding ourselves which gives us a lot of control but also a ton of operational overhead on the other hand managed sharding solutions like vitess or cloud provider options abstract away a lot of the complexity but they can sometimes feel like a black box and i worry about vendor lock-in or unexpected costs down the line what are your experiences with this when did you decide to shard and what approach did you take any war stories or best practices you can share about manual versus managed sharding