diff --git a/src/RimuIO/RimuIO.jl b/src/RimuIO/RimuIO.jl
index 05d15bad9..6f292e267 100644
--- a/src/RimuIO/RimuIO.jl
+++ b/src/RimuIO/RimuIO.jl
@@ -18,7 +18,7 @@ using Rimu.DictVectors: PDVec, DVec, target_segment
 using Rimu.Interfaces: Interfaces, localpart, storage
 using Rimu.StochasticStyles: default_style, IsDynamicSemistochastic
 
-import Tables, Arrow, Arrow.ArrowTypes
+import Rimu, Tables, Arrow, Arrow.ArrowTypes
 
 export save_df, load_df, save_state, load_state
 
@@ -48,6 +48,7 @@ function save_df(
     if metadata === nothing
         metadata = [key => string(val) for (key, val) in DataFrames.metadata(df)]
     end
+    push!(metadata, "RIMU_PACKAGE_VERSION" => string(Rimu.PACKAGE_VERSION))
     Arrow.write(filename, df; compress, metadata, kwargs...)
 end
 
@@ -86,10 +87,11 @@ state is loaded.
 See also [`load_state`](@ref).
 """
 function save_state(args...; kwargs...)
+    new_kwargs = (; RIMU_PACKAGE_VERSION=Rimu.PACKAGE_VERSION, kwargs...)
     if mpi_size() > 1
-        _save_state_mpi(args...; kwargs...)
+        _save_state_mpi(args...; new_kwargs...)
     else
-        _save_state_serial(args...; kwargs...)
+        _save_state_serial(args...; new_kwargs...)
     end
 end
 
@@ -142,6 +144,9 @@ See also [`save_state`](@ref).
 """
 function load_state(::Type{D}, filename; style=nothing, kwargs...) where {D}
     tbl = Arrow.Table(filename)
+    if Tables.schema(tbl).names ≠ (:key, :value)
+        throw(ArgumentError("`$filename` is not a valid Rimu state file"))
+    end
     K = eltype(tbl.key)
     V = eltype(tbl.value)
     if isnothing(style)
@@ -157,12 +162,15 @@ function load_state(::Type{D}, filename; style=nothing, kwargs...) where {D}
     arrow_meta = Arrow.metadata(tbl)[]
     if !isnothing(arrow_meta)
         metadata_pairs = map(collect(arrow_meta)) do (k, v)
+            k == "RIMU_PACKAGE_VERSION" && return Symbol(k) => VersionNumber(v)
             v_int = tryparse(Int, v)
             !isnothing(v_int) && return Symbol(k) => v_int
             v_float = tryparse(Float64, v)
             !isnothing(v_float) && return Symbol(k) => v_float
             v_cmp = tryparse(ComplexF64, v)
             !isnothing(v_cmp) && return Symbol(k) => v_cmp
+            v_bool = tryparse(Bool, v)
+            !isnothing(v_bool) && return Symbol(k) => v_bool
             Symbol(k) => v
         end
         metadata = NamedTuple(metadata_pairs)
diff --git a/test/RimuIO.jl b/test/RimuIO.jl
index 20fed50a2..913cdda51 100644
--- a/test/RimuIO.jl
+++ b/test/RimuIO.jl
@@ -4,7 +4,7 @@ using Arrow
 using Rimu: RimuIO
 using DataFrames
 
-tmpdir = mktempdir()
+const tmpdir = mktempdir()
 
 @testset "save_df, load_df" begin
     file = joinpath(tmpdir, "tmp.arrow")
@@ -83,6 +83,18 @@ end
 
     @testset "vectors" begin
         ham = HubbardReal1D(BoseFS(1,1,1))
+        @testset "errors" begin
+            df1 = DataFrame(key=[1,2,3], value=[1,2,3], error=[0,0,0])
+            save_df(file, df1)
+            @test_throws ArgumentError load_state(file)
+
+            df2 = DataFrame(error=[0,0,0])
+            save_df(file, df2)
+            @test_throws ArgumentError load_state(file)
+
+            rm(file)
+        end
+
         @testset "save DVec" begin
             dvec = ham * DVec([BoseFS(1,1,1) => 1.0, BoseFS(2,1,0) => π])
             save_state(file, dvec)
@@ -117,13 +129,18 @@ end
 
     @testset "metadata" begin
         dvec = DVec(BoseFS(1,1,1,1) => 1.0)
-        save_state(file, dvec; int=1, float=2.3, complex=1.2 + 3im, string="a string")
+        save_state(
+            file, dvec;
+            int=1, float=2.3, complex=1.2 + 3im, string="a string", bool=true
+        )
         _, meta = load_state(file)
 
         @test meta.int === 1
         @test meta.float === 2.3
         @test meta.complex === 1.2 + 3im
+        @test meta.bool === true
         @test meta.string === "a string"
+        @test meta.RIMU_PACKAGE_VERSION == Rimu.PACKAGE_VERSION
         rm(file)
     end