chore: refactor according to clippy & clean up config (#6)

Reviewed-on: #6

Cargo.toml

@@ -72,7 +72,9 @@ debug = 2
 debug-assertions = false
 incremental = false
 lto = 'fat'
-opt-level = 1
+# opt level needs to be benchmarked after every major feature
+# due to the changes in binary size and alignment
+opt-level = 2
 overflow-checks = false
 
 # do not optimize proc-macro crates = faster builds from scratch