diff --git a/src/TwPrototypes.jl b/src/TwPrototypes.jl
index b447d18..0268216 100644
--- a/src/TwPrototypes.jl
+++ b/src/TwPrototypes.jl
@@ -21,7 +21,8 @@ export Chains_section, add_vars, chainscat_resample, chains_par, rename_chain_pa
 export construct_chains_from_csv
 
 
-using SimpleTraits    
+using SimpleTraits: Trait, istrait, @traitdef, @traitimpl, @traitfn  
+import SimpleTraits
 using DataFrames
 import Pkg
 using Requires: @require 
diff --git a/src/requires_mcmcchains.jl b/src/requires_mcmcchains.jl
index 5693670..2ce240a 100644
--- a/src/requires_mcmcchains.jl
+++ b/src/requires_mcmcchains.jl
@@ -101,7 +101,7 @@ function construct_chains_from_csv(chn_df;
     fsections=(vars)->Dict(:internals=>vars[findfirst(==(:lp), vars):end])
     )
     as = map(pairs(groupby(chn_df, :chain))) do (i, subdf)
-        Array(select(subdf, DataFrames.Not(1:2)))
+        Array(select(subdf, Not(1:2)))
     end
     a = reduce((x, y) -> cat(x, y; dims = 3), as)
     MCMCChains.Chains(a, names(chn_df)[3:end], fsections(propertynames(chn_df)[3:end]))
diff --git a/test/runtests.jl b/test/runtests.jl
index f571edb..f1e7557 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -5,7 +5,7 @@ import CSV
 
 @testset "non-required" begin
     #TODO resolve SimpleTraits issue https://github.com/mauro3/SimpleTraits.jl/issues/83
-    #include("test_isofeltype.jl")
+    include("test_isofeltype.jl")
     include("test_util.jl")
     include("test_data_management.jl")
 end