Cannot derive FromSql and ToSql from postgres-types when serving web

[Arkehlor]

Problem

When executing dx serve --web I encounter an issue with the derive macros FromSql & ToSql from the crate postgres-types

I've tried multiple ways to solve the issue that lead to multiple issues of their own:

• adding postgres-types as a simple dependency with derive feature enabled does not work because of multiple compatibility issues (I assume)

15:55:09 [cargo] error: The "wasm_js" backend requires the `wasm_js` feature for `getrandom`. For more information see: https://docs.rs/getrandom/0.3.4/#webassembly-support
  --> C:\Users\Loïc\.cargo\registry\src\index.crates.io-1949cf8c6b5b557f\getrandom-0.3.4\src\backends.rs:40:17
   |
40 | /                 compile_error!(concat!(
41 | |                     "The \"wasm_js\" backend requires the `wasm_js` feature \
42 | |                     for `getrandom`. For more information see: \
43 | |                     https://docs.rs/getrandom/", env!("CARGO_PKG_VERSION"), "/#webassembly-support"
44 | |                 ));
   | |__________________^

15:55:09 [cargo] error[E0425]: cannot find function `fill_inner` in module `backends`                                                                                                                                                                                                                                  
  --> C:\Users\Loïc\.cargo\registry\src\index.crates.io-1949cf8c6b5b557f\getrandom-0.3.4\src\lib.rs:99:19                                                                                                                                                                                                              
   |                                                                                                                                                                                                                                                                                                                   
99 |         backends::fill_inner(dest)?;                                                                                                                                                                                                                                                                              
   |                   ^^^^^^^^^^ not found in `backends`

15:55:09 [cargo] error[E0425]: cannot find function `inner_u32` in module `backends`                                                                                                                                                                                                                                   
   --> C:\Users\Loïc\.cargo\registry\src\index.crates.io-1949cf8c6b5b557f\getrandom-0.3.4\src\lib.rs:123:15                                                                                                                                                                                                            
    |                                                                                                                                                                                                                                                                                                                  
123 |     backends::inner_u32()                                                                                                                                                                                                                                                                                        
    |               ^^^^^^^^^ not found in `backends`
    |
help: consider importing this function
    |
 33 + use crate::util::inner_u32;
    |
help: if you import `inner_u32`, refer to it directly
    |
123 -     backends::inner_u32()
123 +     inner_u32()
    |

15:55:09 [cargo] error[E0425]: cannot find function `inner_u64` in module `backends`                                                                                                                                                                                                                                   
   --> C:\Users\Loïc\.cargo\registry\src\index.crates.io-1949cf8c6b5b557f\getrandom-0.3.4\src\lib.rs:137:15                                                                                                                                                                                                            
    |                                                                                                                                                                                                                                                                                                                  
137 |     backends::inner_u64()                                                                                                                                                                                                                                                                                        
    |               ^^^^^^^^^ not found in `backends`
    |
help: consider importing this function
    |
 33 + use crate::util::inner_u64;
    |
help: if you import `inner_u64`, refer to it directly
    |
137 -     backends::inner_u64()
137 +     inner_u64()
    |

• adding postgres-types as an optional dependency on the server feature with derive feature enabled does not work either

15:58:26 [cargo] error: cannot find derive macro `ToSql` in this scope
  --> src\fluff.rs:16:70
   |
16 | #[derive(Debug, Display, EnumString, PartialEq, Eq, PartialOrd, Ord, ToSql)]
   |                                                                      ^^^^^

• without any surprise, adding postgres-types as an optional dependency on the web feature with derive feature enabled leads to all the same errors as the first method

Relevant code snippets (of the second method)

Enum declaration

#[cfg(feature = "server")]
use postgres_types::ToSql;

#[derive(Debug, Display, EnumString, PartialEq, Eq, PartialOrd, Ord, ToSql)]
pub enum Rarity {
    Common,
    Uncommon,
    Rare,
    Epic,
    Showcase
}

Cargo.toml

[dependencies]
strum = "0.27"
strum_macros = "0.27"
serde = { version = "1.0.228", features = ["derive"] }
serde_json = "1.0.145"
reqwest = "0.12.26"
regex = "1.12.2"
dioxus = { version = "0.7.2", features = ["router", "fullstack"] }
tokio-postgres = { version = "0.7.15", features = ["array-impls"], optional = true }
tokio = { version = "1.48.0", features = ["full"], optional = true }
postgres-types = { version = "0.2.11", features = ["derive"], optional = true }

[features]
default = []
web = ["dioxus/web"]
desktop = ["dioxus/desktop"]
mobile = ["dioxus/mobile"]
server = ["dioxus/server", "dep:tokio-postgres", "dep:tokio", "dep:postgres-types"]

Environment:

• Dioxus version: 0.7.2
• Rust version: rustc 1.92.0 (ded5c06cf 2025-12-08)
• OS info: Microsoft Windows [version 10.0.26200.7462]
• App platform: web

[ealmloff]

You can use cfg_attr to only derive the traits if the server feature is enabled and the server only library is included: https://doc.rust-lang.org/reference/conditional-compilation.html#the-cfg_attr-attribute