diff --git a/.gitignore b/.gitignore
index fe15833de..1bdf03539 100644
--- a/.gitignore
+++ b/.gitignore
@@ -52,3 +52,4 @@ data/prob_dynamic_3_seg.bin.default
 data/ram_air_kite_foil_cd_polar.csv
 data/ram_air_kite_foil_cl_polar.csv
 data/ram_air_kite_foil_cm_polar.csv
+data/prob_dynamic_3_seg.jld2
diff --git a/Project.toml b/Project.toml
index 8bcb2afd3..cf4c5b1e0 100644
--- a/Project.toml
+++ b/Project.toml
@@ -15,6 +15,7 @@ DiscretePIDs = "c1363496-6848-4723-8758-079b737f6baf"
 DocStringExtensions = "ffbed154-4ef7-542d-bbb7-c09d3a79fcae"
 FiniteDiff = "6a86dc24-6348-571c-b903-95158fe2bd41"
 Interpolations = "a98d9a8b-a2ab-59e6-89dd-64a1c18fca59"
+JLD2 = "033835bb-8acc-5ee8-8aae-3f567f8a3819"
 KitePodModels = "9de5dc81-f971-414a-927b-652b2f41c539"
 KiteUtils = "90980105-b163-44e5-ba9f-8b1c83bb0533"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
@@ -60,6 +61,7 @@ DiscretePIDs = "0.1.5"
 DocStringExtensions = "0.9.4"
 Documenter = "1.10.1"
 Interpolations = "0.15.1"
+JLD2 = "0.5.12"
 KitePodModels = "0.3.8"
 KiteUtils = "0.10.2"
 LaTeXStrings = "1.4.0"
diff --git a/src/ram_air_kite.jl b/src/ram_air_kite.jl
index 1a72b5822..cac1467fb 100644
--- a/src/ram_air_kite.jl
+++ b/src/ram_air_kite.jl
@@ -393,11 +393,14 @@ function init_sim!(s::RamAirKite, measure::Measurement; prn=true, precompile=fal
         dt = SimFloat(1/s.set.sample_freq)
         if prn
             @info "Creating ODEProblem"
-            @time s.prob = ODEProblem(s.sys, defaults, (0.0, dt); guesses)
+            @time begin expr = ODEProblemExpr(s.sys, defaults, (0.0, dt); guesses); s.prob = eval(expr) end
         else
-            s.prob = ODEProblem(s.sys, defaults, (0.0, dt); guesses)
+            expr = ODEProblemExpr(s.sys, defaults, (0.0, dt); guesses); s.prob = eval(expr)
         end
-        serialize(prob_path, s.prob)
+        # serialize(prob_path, s.prob)
+        # ODEProblemExpr
+        save_prob(prob_path, expr)
+
         s.integrator = nothing
     end
     prob_path = joinpath(KiteUtils.get_data_path(), get_prob_name(s.set; precompile))
@@ -458,7 +461,8 @@ function reinit!(s::RamAirKite, measure::Measurement; prn=true, reload=true, pre
         prob_path = joinpath(KiteUtils.get_data_path(), get_prob_name(s.set; precompile))
         !ispath(prob_path) && throw(ArgumentError("$prob_path not found. Run init_sim!(s::RamAirKite) first."))
         try
-            s.prob = deserialize(prob_path)
+            # s.prob = deserialize(prob_path)
+            s.prob = load_prob(prob_path)
         catch e
             @warn "Failure to deserialize $prob_path !"
             throw(e)
@@ -559,9 +563,9 @@ function get_prob_name(set::Settings; precompile=false)
         suffix = ".default"
     end
     if set.quasi_static
-        return "prob_static_" * string(set.segments) * "_seg.bin" * suffix
+        return "prob_static_" * string(set.segments) * "_seg.jld2" * suffix
     else
-        return "prob_dynamic_" * string(set.segments) * "_seg.bin" * suffix
+        return "prob_dynamic_" * string(set.segments) * "_seg.jld2" * suffix
     end
 end