Serde alias not working

Im expecting to put alias to each fields in a struct where the alias name are the keys from os env

#[derive(Debug, Deserialize, Clone)]
pub struct BuildInfo {
    #[serde(alias = "VERSION")]
    pub app_version: String,
}

in my os env:

VERSION=1.2.3

When I build with:

let builder = Config::builder().add_source(Environment::default()).build();
builder.unwrap().try_deserialize::<BuildInfo>().unwrap()

I got panic error: value: missing field app_version``

If I change with serde rename I got:
value: missing field VERSION

it works if I just change the letter case like from VERSION to version, but I need way to map this.

How to map easily from os env with different keys name to structs with different keys name?

Reproduce the issue with the shown BuildInfo struct, VERSION environment variable, and Environment source. Trace how environment keys are normalized and passed to serde, then verify that the intended mapping from VERSION to app_version is either supported or clearly documented.