diff --git a/.github/workflows/CI.yml b/.github/workflows/CI.yml
index 1eeea46..5cf8c5d 100644
--- a/.github/workflows/CI.yml
+++ b/.github/workflows/CI.yml
@@ -19,6 +19,7 @@ jobs:
           - '1.6'
           - '1.9'
           - '1.10'
+          - '1.12'
           - 'nightly'
         os:
           - ubuntu-latest
diff --git a/.gitignore b/.gitignore
index 27d5738..97105e3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,7 @@
-/Manifest.toml
-/docs/Manifest.toml
+/Manifest*.toml
+/docs/Manifest*.toml
 /docs/build/
 *.code-workspace
-Manifest.toml
-LocalPreferences.toml
\ No newline at end of file
+Manifest*.toml
+LocalPreferences.toml
+.vscode/
\ No newline at end of file
diff --git a/src/define_interface.jl b/src/define_interface.jl
index 72fbf24..c10625e 100644
--- a/src/define_interface.jl
+++ b/src/define_interface.jl
@@ -2,34 +2,34 @@ _propertynames(T::Type) = Base.fieldnames(T)
 _propertynames(x) = Base.propertynames(x)
 
 @generated function validate_properties(::Type{S}, delegated_fieldnames::Type{T}) where {S, T <: Tuple}
-    output = Expr(:block, :(unique_properties = Set{Symbol}($Base.fieldnames($S))))
+    output_args = Any[:(local unique_properties = Set{Symbol}($Base.fieldnames($S)))]
     recursive = fieldtype(T, 1) === Val{:recursive}
     for i in 2:fieldcount(T)
         key = fieldtype(T, i)
         props = Symbol(key, :_properties)
         child_T = fieldtype(S, key)
         if recursive 
-            push!(output.args, :($props = Set{Symbol}( $_propertynames($child_T))))
+            push!(output_args, :(local $props = Set{Symbol}( $_propertynames($child_T))))
         else
-            push!(output.args, :($props = Set{Symbol}( $fieldnames($child_T))))
+            push!(output_args, :(local $props = Set{Symbol}( $fieldnames($child_T))))
         end
 
-        push!( output.args, :( diff = $intersect(unique_properties, $(props)) ), :(!isempty(diff) && error("Duplicate properties `$(sort(collect(diff)))` found for type $($(S)) in child `$($(QuoteNode(key)))::$($(child_T))` ")), :($union!(unique_properties, $props)))
+        push!( output_args, :( diff = $intersect(unique_properties, $(props)) ), :(!isempty(diff) && error("Duplicate properties `$(sort(collect(diff)))` found for type $($(S)) in child `$($(QuoteNode(key)))::$($(child_T))` ")), :($union!(unique_properties, $props)))
     end
-    push!(output.args, :(return nothing))
-    return output
+    push!(output_args, :(return nothing))
+    return Expr(:block, output_args...)
 end
 
 @generated function _propertynames(::Type{S}, delegated_fields::Type{T}) where {S, T <: Tuple}
     Base.isstructtype(S) || error("$S is not a struct type")
-    output = Expr(:tuple, QuoteNode.(fieldnames(S))...)
+    output_args = Any[QuoteNode.(fieldnames(S))...]
     recursive = fieldtype(T, 1) === Val{:recursive}
     for i in 2:fieldcount(T)
         key = fieldtype(T,i)
         Si = fieldtype(S, key)
-        push!(output.args, recursive ? :($_propertynames($(Si))...) : :($fieldnames($(Si))...))
+        push!(output_args, recursive ? :($_propertynames($(Si))...) : :($fieldnames($(Si))...))
     end
-    return output
+    return Expr(:tuple, output_args...)
 end
 _propertynames(x, delegated_fields) = _propertynames(typeof(x), delegated_fields)
 
@@ -88,6 +88,7 @@ If `ensure_unique == true`, throws an error when there are nonunique names in th
 
 """
 function properties_interface(T; delegated_fields, recursive::Bool=false, ensure_unique::Bool=true, kwargs...)
+    @nospecialize
     if haskey(kwargs, :is_mutable)
         Base.depwarn("Passing `is_mutable` kwarg when `interface=properties` is now deprecated", Symbol("@define_interface"))
         is_mutable = get_kwarg(Bool, kwargs, :is_mutable, false)
@@ -110,14 +111,15 @@ function properties_interface(T; delegated_fields, recursive::Bool=false, ensure
     _setproperty = :($ForwardMethods._setproperty!($obj::$T, $name::Symbol, $value) = $ForwardMethods._setproperty!($obj, $delegated_fields_tuple_type, $name, $value))
     setproperty = :($Base.setproperty!($obj::$T, $name::Symbol, $value) = $ForwardMethods._setproperty!($obj, $name, $value))
 
-    output = Expr(:block, line_num)
+    output_args = Any[]
     if ensure_unique
-        push!(output.args, :($validate_properties($T, $delegated_fields_tuple_type)))
+        push!(output_args, :($validate_properties($T, $delegated_fields_tuple_type)))
     end
-    push!(output.args, map(linenum!, (_propertynames, _propertynamesT, propertynames, _getproperty, getproperty))...)
+    push!(output_args, map(linenum!, (_propertynames, _propertynamesT, propertynames, _getproperty, getproperty))...)
     if is_mutable
-        push!(output.args, map(linenum!, (_setproperty, setproperty))...)
+        push!(output_args, map(linenum!, (_setproperty, setproperty))...)
     end
+    output = Expr(:block, line_num, output_args...)
     return wrap_define_interface(T, :properties, output)
 end
 
@@ -138,6 +140,7 @@ Any values provided in `omit` are excluded from the generator expression above.
     
 """
 function equality_interface(T; omit::AbstractVector{Symbol}=Symbol[], equality_op::Symbol=:(==), compare_fields::Symbol=:fieldnames)
+    @nospecialize
     equality_op in (:(==), :isequal) || error("equality_op (= $equality_op) must be one of (==, isequal)")
     if compare_fields == :fieldnames 
         getvalue = :($Base.getfield)
@@ -166,9 +169,10 @@ end
 @method_def_constant define_interface_method(::Val{::Symbol}) define_interfaces_available
 
 function define_interface_expr(T, kwargs::Dict{Symbol,Any}=Dict{Symbol,Any}(); _sourceinfo)
+    @nospecialize
     interfaces = interface_kwarg!(kwargs)
     omit = omit_kwarg!(kwargs)
-    output = Expr(:block)
+    output_args = Any[]
     interfaces_available = define_interfaces_available()
     for interface in interfaces
         interface in interfaces_available || error("No interface found with name $interface -- must be one of `$interfaces_available`")
@@ -176,12 +180,12 @@ function define_interface_expr(T, kwargs::Dict{Symbol,Any}=Dict{Symbol,Any}(); _
 
         current_line_num[] = _sourceinfo
         try 
-            push!(output.args, f(T; omit, kwargs...))
+            push!(output_args, f(T; omit, kwargs...))
         finally 
             current_line_num[] = nothing 
         end
     end
-    return output
+    return Expr(:block, output_args...)
 end
 
 """
diff --git a/src/forward_interface.jl b/src/forward_interface.jl
index 7870dd2..0ab706e 100644
--- a/src/forward_interface.jl
+++ b/src/forward_interface.jl
@@ -5,6 +5,7 @@ interface_at_macroexpand_time(x) = true
 base_forward_expr(f, args...) = Expr(:call, f, args...)
 
 function forward_interface_args(T)
+    @nospecialize
     t = gensym(arg_placeholder)
     obj_arg = object_argument(t, T)
     type_arg = type_argument(T)
@@ -102,6 +103,7 @@ according to the value of `index_style_linear`
 Any function names specified in `omit::AbstractVector{Symbol}` will not be defined
 """
 function array_interface(T; index_style_linear::Bool, omit::AbstractVector{Symbol}=Symbol[])
+    @nospecialize
     obj_arg, type_arg, call_expr = forward_interface_args(T)
 
     method_signatures = Any[
@@ -242,13 +244,14 @@ function getfields_interface(T; field::Union{Nothing,Symbol}=nothing, omit::Abst
     return wrap_define_interface(T, :getfields, Base.remove_linenums!(quote 
         local omit_fields = $(Expr(:tuple, QuoteNode.(omit)...))
         local fields = fieldnames($T)
-        local def_fields_expr = Expr(:block)
         local var = gensym("x")
+        local def_fields_expr_args = Any[]
         for field in fields 
             if field ∉ omit_fields
-                push!(def_fields_expr.args, :($field($var::$$T) = Base.getfield($var, $(QuoteNode(field)))))
+                push!(def_fields_expr_args, :($field($var::$$T) = Base.getfield($var, $(QuoteNode(field)))))
             end
         end
+        local def_fields_expr = Expr(:block, def_fields_expr_args...)
         eval(def_fields_expr)
         nothing
     end))
@@ -265,13 +268,14 @@ function setfields_interface(T; field::Union{Nothing,Symbol}=nothing, omit::Abst
     return wrap_define_interface(T, :setfields, Base.remove_linenums!(quote 
         local omit_fields = $(Expr(:tuple, QuoteNode.(omit)...))
         local fields = fieldnames($T)
-        local def_fields_expr = Expr(:block)
         local var = gensym("x")
+        local def_fields_expr_args = Any[]
         for field in fields 
             if field ∉ omit_fields
-                push!(def_fields_expr.args, :($(Symbol(string(field)*"!"))($var::$$T, value) = Base.setfield!($var, $(QuoteNode(field)), value)))
+                push!(def_fields_expr_args, :($(Symbol(string(field)*"!"))($var::$$T, value) = Base.setfield!($var, $(QuoteNode(field)), value)))
             end
         end
+        local def_fields_expr = Expr(:block, def_fields_expr_args...)
         eval(def_fields_expr)
         nothing
     end))
@@ -309,8 +313,7 @@ function forward_interface_expr(T, kwargs::Dict{Symbol,Any}=Dict{Symbol,Any}();
         field_funcs = nothing
     end
 
-    _output = Expr(:block)
-
+    _output_args = Any[]
     available_interfaces = forward_interfaces_available()
 
     for interface in interfaces
@@ -325,16 +328,16 @@ function forward_interface_expr(T, kwargs::Dict{Symbol,Any}=Dict{Symbol,Any}();
                 isnothing(field_funcs.type_func) && error("Only fieldname mode for `field` (= $field) supported for interface (= $interface_value)") 
             end
             signatures = f(T; omit, kwargs...)
-            output = Expr(:block)
+            output_args = Any[]
             for signature in signatures 
-                push!(output.args, forward_method_signature(T, field_funcs, map_func, signature; _sourceinfo))
+                push!(output_args, forward_method_signature(T, field_funcs, map_func, signature; _sourceinfo))
             end
-            push!(_output.args, output)
+            push!(_output_args, Expr(:block, output_args...))
         else 
-            push!(_output.args, f(T; omit, kwargs...))
+            push!(_output_args, f(T; omit, kwargs...))
         end
     end
-    return _output
+    return Expr(:block, _output_args...)
 end
 
 """
diff --git a/src/forward_methods.jl b/src/forward_methods.jl
index 5c6a1e8..91d0ece 100644
--- a/src/forward_methods.jl
+++ b/src/forward_methods.jl
@@ -106,24 +106,27 @@ function forward_method_signature(Type, field_funcs::FieldFuncExprs, map_func::F
     if !found
         error("No argument matching type $Type in input = `$input`")
     end
-    func_body = Expr(:call, funcname)
+    func_body_args = Any[funcname]
     if !isempty(kwargs)
-        push!(func_body.args, Expr(:parameters, kwargs...))
+        push!(func_body_args, Expr(:parameters, kwargs...))
     end
-    push!(func_body.args, output_args...)
-    body_block = Expr(:block)
+    push!(func_body_args, output_args...)
+    func_body = Expr(:call, func_body_args...)
+    body_block_args = Any[]
     if !isnothing(_sourceinfo)
-        push!(body_block.args, _sourceinfo)
+        push!(body_block_args, _sourceinfo)
     end
-    push!(body_block.args, found_arg_expr)
+    push!(body_block_args, found_arg_expr)
     mapped_body = !found_arg_is_type ? map_func(found_input_arg, func_body) : func_body
-    push!(body_block.args, mapped_body)
+    push!(body_block_args, mapped_body)
+    body_block = Expr(:block, body_block_args...)
 
-    new_sig = Expr(:call, funcname)
+    new_sig_args = Any[funcname]
     if !isempty(kwargs)
-        push!(new_sig.args, Expr(:parameters, kwargs...))
+        push!(new_sig_args, Expr(:parameters, kwargs...))
     end
-    push!(new_sig.args, input_args...)
+    push!(new_sig_args, input_args...)
+    new_sig = Expr(:call, new_sig_args...)
     if !isnothing(whereparams)
         new_sig = Expr(:where, new_sig, whereparams...)
     end
@@ -226,7 +229,7 @@ function forward_methods_expr(Type, field_expr, args...; _sourceinfo=nothing)
         method_exprs = args 
     end
 
-    output = Expr(:block)
+    output_args = Any[]
     for arg in method_exprs
         _args = @switch arg begin 
             @case Expr(:block, args...)
@@ -235,10 +238,10 @@ function forward_methods_expr(Type, field_expr, args...; _sourceinfo=nothing)
                 [arg]
         end
         for arg in _args
-            push!(output.args, forward_method_signature(Type, field_funcs, map_func, arg; _sourceinfo))
+            push!(output_args, forward_method_signature(Type, field_funcs, map_func, arg; _sourceinfo))
         end
     end
-    return output
+    return Expr(:block, output_args...)
 end
 
 """
diff --git a/src/util.jl b/src/util.jl
index 2d481b7..e2def64 100644
--- a/src/util.jl
+++ b/src/util.jl
@@ -50,13 +50,13 @@ replace_placeholder(x, replace_values) = (x, false)
 
 function replace_placeholder(x::Expr, replace_values::Vector{<:Pair{Symbol,<:Any}})
     replaced = false
-    new_expr = Expr(x.head)
+    new_expr_args = Any[]
     for arg in x.args 
         new_arg, arg_replaced = replace_placeholder(arg, replace_values)
-        push!(new_expr.args, new_arg)
+        push!(new_expr_args, new_arg)
         replaced |= arg_replaced
     end
-    return new_expr, replaced
+    return Expr(x.head, new_expr_args...), replaced
 end
 
 identity_map_expr(obj_expr, forwarded_expr) = forwarded_expr
@@ -113,7 +113,7 @@ function omit_kwarg!(kwargs::Dict{Symbol,Any})
     end
 end
 
-function get_kwarg(::Type{T}, kwargs, key::Symbol, default) where {T}
+function get_kwarg(T::Type, kwargs, key::Symbol, default)
     value = get(kwargs, key, default)
     value isa T || error("$key (= $value) must be a $T, got typeof($key) = $(typeof(value))")
     return value
diff --git a/test/Project.toml b/test/Project.toml
index a5cbb92..1bc7897 100644
--- a/test/Project.toml
+++ b/test/Project.toml
@@ -1,6 +1,5 @@
 [deps]
 Aqua = "4c88cf16-eb10-579e-8560-4a9242c79595"
-JET = "c3a54625-cd67-489e-a8e7-0a5a0ff4e31b"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 TestItemRunner = "f8b46487-2199-4994-9208-9a1283c18c0a"
 TestItems = "1c621080-faea-4a02-84b6-bbd5e436b8fe"
diff --git a/test/runtests.jl b/test/runtests.jl
index 596e423..5f86725 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -1,7 +1,7 @@
-using ForwardMethods
 using TestItemRunner
 
 if VERSION ≥ v"1.9"
+    using ForwardMethods
     using Aqua
     Aqua.test_all(ForwardMethods)
 end
diff --git a/test/setup.jl b/test/setup.jl
index 3f39f79..6a5b24d 100644
--- a/test/setup.jl
+++ b/test/setup.jl
@@ -3,7 +3,7 @@ using TestItemRunner, TestItems
 @testsnippet SetupTest begin 
     using ForwardMethods.MLStyle 
 
-    using JET, Test, TestingUtilities 
+    using Test, TestingUtilities 
 
     macro test_throws_compat(ExceptionType, message, expr)
         output = Expr(:block, __source__, :($Test.@test_throws $ExceptionType $expr))
diff --git a/test/test_forward_methods.jl b/test/test_forward_methods.jl
index 15b5110..56dff8a 100644
--- a/test/test_forward_methods.jl
+++ b/test/test_forward_methods.jl
@@ -192,9 +192,7 @@
             @Test B([0])[1] == 0
             c = C([1])
             @Test length(c) == 1
-            @static if VERSION >= v"1.9"
-                @test_opt length(c) 
-            end
+            
         end
     end
 end
\ No newline at end of file