diff --git a/Project.toml b/Project.toml
index 96d8ebc..ba69134 100644
--- a/Project.toml
+++ b/Project.toml
@@ -11,6 +11,7 @@ ColorSchemes = "35d6a980-a343-548e-a6ea-1d62b119f2f4"
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"
 Distributions = "31c24e10-a181-5473-b8eb-7969acd0382f"
 GLMakie = "e9467ef8-e4e7-5192-8a1a-b1aee30e663a"
+Intervals = "d8418881-c3e1-53bb-8760-2df7ec849ed5"
 JLD2 = "033835bb-8acc-5ee8-8aae-3f567f8a3819"
 JSON3 = "0f8b85d8-7281-11e9-16c2-39a750bddbf1"
 JuliaFormatter = "98e50ef6-434e-11e9-1051-2b60c6c9e899"
@@ -18,6 +19,7 @@ LaTeXStrings = "b964fa9f-0449-5b57-a5c2-d3ea65f4040f"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 LoopVectorization = "bdcacae8-1622-11e9-2a5c-532679323890"
 Luxor = "ae8d54c2-7ccd-5906-9d76-62fc9837b5bc"
+OrderedCollections = "bac558e1-5e72-5ebc-8fee-abe8a469f55d"
 ProfileView = "c46f51b8-102a-5cf2-8d2c-8597cb0e0da7"
 ProgressMeter = "92933f4c-e287-5a05-a399-4b506db050ca"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
diff --git a/src/ReCo.jl b/src/ReCo.jl
index cd1eb19..a37d6fa 100644
--- a/src/ReCo.jl
+++ b/src/ReCo.jl
@@ -2,6 +2,7 @@ module ReCo
 
 export init_sim, run_sim
 
+include("utils.jl")
 include("PreVector.jl")
 include("Particle.jl")
 include("reinforcement_learning.jl")
diff --git a/src/data.jl b/src/data.jl
index 340171f..dd6e696 100644
--- a/src/data.jl
+++ b/src/data.jl
@@ -35,7 +35,7 @@ end
 
 function set_sim_state(dir::String, n_bundles::Int64, T::Float64)
     open("$dir/sim_state.json", "w") do f
-        JSON3.write(f, Dict("n_bundles" => n_bundles, "T" => round(T; digits=3)))
+        JSON3.write(f, (n_bundles=n_bundles, T=round(T; digits=3)))
     end
 
     return nothing
diff --git a/src/run.jl b/src/run.jl
index a53c1ee..250b128 100644
--- a/src/run.jl
+++ b/src/run.jl
@@ -13,7 +13,7 @@ function run_sim(
 )
     @assert length(dir) > 0
     @assert duration > 0
-    @assert snapshot_at in 0.01:0.01:duration
+    @assert snapshot_at in 0.001:0.001:duration
     @assert n_steps_before_verlet_list_update >= 0
     @assert seed > 0
     @assert n_bundle_snapshots >= 0
diff --git a/src/utils.jl b/src/utils.jl
new file mode 100644
index 0000000..16fcf30
--- /dev/null
+++ b/src/utils.jl
@@ -0,0 +1,16 @@
+using JSON3: JSON3
+using OrderedCollections: OrderedDict
+
+function struct_to_ordered_dict(s)
+    return OrderedDict(key => getfield(s, key) for key in propertynames(s))
+end
+
+function write_struct_to_json(s, path_without_extension::String)
+    ordered_dict = struct_to_ordered_dict(s)
+
+    open("$path_without_extension.json", "w") do f
+        JSON3.write(f, ordered_dict)
+    end
+
+    return nothing
+end
\ No newline at end of file