postgres@8906faf9cf1d:~/pgx_json_schema$ cargo pgx package
    Building extension with features
     Running command "cargo" "build" "--release" "--message-format=json-render-diagnostics"
   Compiling pgx_json_schema v0.2.2 (/var/lib/postgresql/pgx_json_schema)
error: custom attribute panicked
 --> src/json_schema.rs:9:1
  |
9 | #[pg_extern]
  | ^^^^^^^^^^^^
  |
  = help: message: called `Result::unwrap()` on an `Err` value: Error("Got unknown return type: ImplTrait(TypeImplTrait { impl_token: Impl, bounds: [Trait(TraitBound { paren_
token: None, modifier: None, lifetimes: None, path: Path { leading_colon: None, segments: [PathSegment { ident: Ident { ident: \"std\", span: #0 bytes(3595..3598) }, argument
s: None }, Colon2, PathSegment { ident: Ident { ident: \"iter\", span: #0 bytes(3600..3604) }, arguments: None }, Colon2, PathSegment { ident: Ident { ident: \"Iterator\", sp
an: #0 bytes(3606..3614) }, arguments: AngleBracketed(AngleBracketedGenericArguments { colon2_token: None, lt_token: Lt, args: [Binding(Binding { ident: Ident { ident: \"Item
\", span: #0 bytes(3620..3624) }, eq_token: Eq, ty: Tuple(TypeTuple { paren_token: Paren, elems: [Macro(TypeMacro { mac: Macro { path: Path { leading_colon: None, segments: [
PathSegment { ident: Ident { ident: \"name\", span: #0 bytes(3637..3641) }, arguments: None }] }, bang_token: Bang, delimiter: Paren(Paren), tokens: TokenStream [Ident { iden
t: \"error_value\", span: #0 bytes(3643..3654) }, Punct { ch: ',', spacing: Alone, span: #0 bytes(3654..3655) }, Ident { ident: \"JsonB\", span: #0 bytes(3656..3661) }] } }),
 Comma, Macro(TypeMacro { mac: Macro { path: Path { leading_colon: None, segments: [PathSegment { ident: Ident { ident: \"name\", span: #0 bytes(3672..3676) }, arguments: Non
e }] }, bang_token: Bang, delimiter: Paren(Paren), tokens: TokenStream [Ident { ident: \"description\", span: #0 bytes(3678..3689) }, Punct { ch: ',', spacing: Alone, span: #
0 bytes(3689..3690) }, Ident { ident: \"String\", span: #0 bytes(3691..3697) }] } }), Comma, Macro(TypeMacro { mac: Macro { path: Path { leading_colon: None, segments: [PathS
egment { ident: Ident { ident: \"name\", span: #0 bytes(3708..3712) }, arguments: None }] }, bang_token: Bang, delimiter: Paren(Paren), tokens: TokenStream [Ident { ident: \"
details\", span: #0 bytes(3714..3721) }, Punct { ch: ',', spacing: Alone, span: #0 bytes(3721..3722) }, Ident { ident: \"String\", span: #0 bytes(3723..3729) }] } }), Comma,
Macro(TypeMacro { mac: Macro { path: Path { leading_colon: None, segments: [PathSegment { ident: Ident { ident: \"name\", span: #0 bytes(3740..3744) }, arguments: None }] },
bang_token: Bang, delimiter: Paren(Paren), tokens: TokenStream [Ident { ident: \"instance_path\", span: #0 bytes(3746..3759) }, Punct { ch: ',', spacing: Alone, span: #0 byte
s(3759..3760) }, Ident { ident: \"String\", span: #0 bytes(3761..3767) }] } }), Comma, Macro(TypeMacro { mac: Macro { path: Path { leading_colon: None, segments: [PathSegment
 { ident: Ident { ident: \"name\", span: #0 bytes(3778..3782) }, arguments: None }] }, bang_token: Bang, delimiter: Paren(Paren), tokens: TokenStream [Ident { ident: \"schema
_path\", span: #0 bytes(3784..3795) }, Punct { ch: ',', spacing: Alone, span: #0 bytes(3795..3796) }, Ident { ident: \"String\", span: #0 bytes(3797..3803) }] } }), Comma] })
 }), Comma], gt_token: Gt }) }] } })] })")

error: custom attribute panicked
  --> src/json_type_def.rs:13:1
   |
13 | #[pg_extern]
   | ^^^^^^^^^^^^
   |
   = help: message: called `Result::unwrap()` on an `Err` value: Error("Got unknown return type: ImplTrait(TypeImplTrait { impl_token: Impl, bounds: [Trait(TraitBound { paren_token: None, modifier: None, lifetimes: None, path: Path { leading_colon: None, segments: [PathSegment { ident: Ident { ident: \"std\", span: #0 bytes(5601..5604) }, arguments: None }, Colon2, PathSegment { ident: Ident { ident: \"iter\", span: #0 bytes(5606..5610) }, arguments: None }, Colon2, PathSegment { ident: Ident { ident: \"Iterator\", span: #0 bytes(5612..5620) }, arguments: AngleBracketed(AngleBracketedGenericArguments { colon2_token: None, lt_token: Lt, args: [Binding(Binding { ident: Ident { ident: \"Item\", span: #0 bytes(5621..5625) }, eq_token: Eq, ty: Tuple(TypeTuple { paren_token: Paren, elems: [Macro(TypeMacro { mac: Macro { path: Path { leading_colon: None, segments: [PathSegment { ident: Ident { ident: \"name\", span: #0 bytes(5629..5633) }, arguments: None }] }, bang_token: Bang, delimiter: Paren(Paren), tokens: TokenStream [Ident { ident: \"instance_path\", span: #0 bytes(5635..5648) }, Punct { ch: ',', spacing: Alone, span: #0 bytes(5648..5649) }, Ident { ident: \"String\", span: #0 bytes(5650..5656) }] } }), Comma, Macro(TypeMacro { mac: Macro { path: Path { leading_colon: None, segments: [PathSegment { ident: Ident { ident: \"name\", span: #0 bytes(5659..5663) }, arguments: None }] }, bang_token: Bang, delimiter: Paren(Paren), tokens: TokenStream [Ident { ident: \"schema_path\", span: #0 bytes(5665..5676) }, Punct { ch: ',', spacing: Alone, span: #0 bytes(5676..5677) }, Ident { ident: \"String\", span: #0 bytes(5678..5684) }] } })] }) })], gt_token: Gt }) }] } })] })")

warning: unused import: `jsonschema::JSONSchema`
 --> src/json_schema.rs:1:5
  |
1 | use jsonschema::JSONSchema;
  |     ^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: `#[warn(unused_imports)]` on by default

warning: `pgx_json_schema` (lib) generated 1 warning
error: could not compile `pgx_json_schema` due to 2 previous errors; 1 warning emitted