Slow compile times

[maxcountryman]

It seems that something is causing excessively slow compile times. For instance, adding a simple println! costs nearly 40 seconds to recompile:

$ cargo run --database-url ...
   Compiling warp-api-starter-template v0.1.0 (/Users/max/Repositories/warp-api-starter-template)
    Finished dev [unoptimized + debuginfo] target(s) in 39.35s
     Running `target/debug/warp-api-starter-template`

Where the only change is:

diff --git a/src/environment/argon.rs b/src/environment/argon.rs
index b70bcd5..ce58cc9 100644
--- a/src/environment/argon.rs
+++ b/src/environment/argon.rs
@@ -15,6 +15,7 @@ impl Argon {
             argon_iterations,
             ..
         } = args;
+        println!("foo");
         Self {
             secret: argon_secret.to_owned(),
             memory_size: argon_memory_size.to_owned(),

This is actually decently faster than other compile times I've observed, which sometimes exceed two minutes (!) but are not significant changes.

Depending on your development style, this may be a showstopper.

[aslamplr]

Any recommendations on improving the compile times are welcome.

[aslamplr]

#12 might help in the case of slow compile times. Rust considers crate as a compilation unit and ATM warp-api-starter-template is huge crate and spliting it into multiple dependent crate might allow for better compile times. This is not tested notion for me. I need to try it out and see.

[maxcountryman]

@aslamplr I think you're right that breaking things up into component crates could help. At the very least, it should avoid to always recompile everything.