diff --git a/Manifest.toml b/Manifest.toml
index 26dd24095..7acc88738 100644
--- a/Manifest.toml
+++ b/Manifest.toml
@@ -1312,7 +1312,7 @@ uuid = "295af30f-e4ad-537b-8983-00126c2a3abe"
 version = "3.5.18"
 
 [[deps.Ribasim]]
-deps = ["Accessors", "Arrow", "BasicModelInterface", "CodecZstd", "ComponentArrays", "Configurations", "DBInterface", "DataInterpolations", "DataStructures", "Dates", "DiffEqCallbacks", "EnumX", "FiniteDiff", "ForwardDiff", "Graphs", "HiGHS", "IterTools", "JuMP", "Legolas", "LineSearches", "LinearSolve", "Logging", "LoggingExtras", "MetaGraphsNext", "OrdinaryDiffEq", "PreallocationTools", "ReadOnlyArrays", "SQLite", "SciMLBase", "SparseArrays", "StructArrays", "Tables", "TerminalLoggers", "TimerOutputs", "TranscodingStreams"]
+deps = ["Accessors", "Arrow", "BasicModelInterface", "CodecZstd", "ComponentArrays", "Configurations", "DBInterface", "DataInterpolations", "DataStructures", "Dates", "DiffEqCallbacks", "EnumX", "FiniteDiff", "ForwardDiff", "Graphs", "HiGHS", "IterTools", "JuMP", "Legolas", "LinearSolve", "Logging", "LoggingExtras", "MetaGraphsNext", "OrdinaryDiffEq", "PreallocationTools", "ReadOnlyArrays", "SQLite", "SciMLBase", "SparseArrays", "StructArrays", "Tables", "TerminalLoggers", "TimerOutputs", "TranscodingStreams"]
 path = "core"
 uuid = "aac5e3d9-0b8f-4d4f-8241-b1a7a9632635"
 version = "2024.10.0"
diff --git a/core/Project.toml b/core/Project.toml
index cac0c9446..d66d26907 100644
--- a/core/Project.toml
+++ b/core/Project.toml
@@ -24,7 +24,6 @@ HiGHS = "87dc4568-4c63-4d18-b0c0-bb2238e4078b"
 IterTools = "c8e1da08-722c-5040-9ed9-7db0dc04731e"
 JuMP = "4076af6c-e467-56ae-b986-b466b2749572"
 Legolas = "741b9549-f6ed-4911-9fbf-4a1c0c97f0cd"
-LineSearches = "d3d80556-e9d4-5f37-9878-2ab0fcc64255"
 LinearSolve = "7ed4a6bd-45f5-4d41-b270-4a48e9bafcae"
 Logging = "56ddb016-857b-54e1-b83d-db4d58db5568"
 LoggingExtras = "e6f89c97-d47a-5376-807f-9c37f3926c36"
@@ -73,7 +72,6 @@ IterTools = "1.4"
 JuMP = "1.15"
 Legolas = "0.5"
 LinearSolve = "2.24"
-LineSearches = "7.2"
 Logging = "<0.0.1, 1"
 LoggingExtras = "1"
 Makie = "0.21"
diff --git a/core/src/config.jl b/core/src/config.jl
index 11e97608d..c7ef41eec 100644
--- a/core/src/config.jl
+++ b/core/src/config.jl
@@ -11,7 +11,6 @@ module config
 using Configurations: Configurations, @option, from_toml, @type_alias
 using DataStructures: DefaultDict
 using Dates: DateTime
-using LineSearches: BackTracking
 using Logging: LogLevel, Debug, Info, Warn, Error
 using ..Ribasim: Ribasim, isnode, nodetype
 using OrdinaryDiffEq:
@@ -241,7 +240,7 @@ function algorithm(solver::Solver)::OrdinaryDiffEqAlgorithm
     end
     kwargs = Dict{Symbol, Any}()
     if algotype <: OrdinaryDiffEqNewtonAdaptiveAlgorithm
-        kwargs[:nlsolve] = NLNewton(; relax = BackTracking())
+        kwargs[:nlsolve] = NLNewton(; relax = 0.1)
     end
     # not all algorithms support this keyword
     kwargs[:autodiff] = solver.autodiff
diff --git a/core/test/run_models_test.jl b/core/test/run_models_test.jl
index fdf31bf77..340f819df 100644
--- a/core/test/run_models_test.jl
+++ b/core/test/run_models_test.jl
@@ -206,7 +206,7 @@ end
 
     @test successful_retcode(model)
     @test allunique(Ribasim.tsaves(model))
-    @test model.integrator.sol.u[end] ≈ Float32[519.8817, 519.8798, 339.3959, 1418.4331] skip =
+    @test model.integrator.u ≈ Float32[519.8817, 519.8798, 339.3959, 1418.4331] skip =
         Sys.isapple() atol = 1.5
 
     @test length(logger.logs) > 10
@@ -241,8 +241,8 @@ end
     @test allunique(Ribasim.tsaves(model))
     precipitation = Ribasim.get_tmp(model.integrator.p.basin.vertical_flux, 0).precipitation
     @test length(precipitation) == 4
-    @test model.integrator.sol.u[end] ≈ Float32[471.9218, 471.9199, 363.6981, 1427.962] skip =
-        Sys.isapple()
+    @test model.integrator.u ≈ Float32[472.06555, 472.06366, 367.23883, 1427.9957] atol =
+        2.0 skip = Sys.isapple()
 end
 
 @testitem "Allocation example model" begin
@@ -276,14 +276,14 @@ end
     @test successful_retcode(sparse_fdm)
     @test successful_retcode(dense_fdm)
 
-    @test dense_ad.integrator.sol.u[end] ≈ sparse_ad.integrator.sol.u[end] atol = 0.1
-    @test sparse_fdm.integrator.sol.u[end] ≈ sparse_ad.integrator.sol.u[end] atol = 4
-    @test dense_fdm.integrator.sol.u[end] ≈ sparse_ad.integrator.sol.u[end] atol = 4
+    @test dense_ad.integrator.u ≈ sparse_ad.integrator.u atol = 0.1
+    @test sparse_fdm.integrator.u ≈ sparse_ad.integrator.u atol = 4
+    @test dense_fdm.integrator.u ≈ sparse_ad.integrator.u atol = 4
 
     config = Ribasim.Config(toml_path; solver_algorithm = "Rodas5", solver_autodiff = true)
     time_ad = Ribasim.run(config)
     @test successful_retcode(time_ad)
-    @test time_ad.integrator.sol.u[end] ≈ sparse_ad.integrator.sol.u[end] atol = 4
+    @test time_ad.integrator.u ≈ sparse_ad.integrator.u atol = 4
 end
 
 @testitem "TabulatedRatingCurve model" begin
@@ -295,7 +295,7 @@ end
     model = Ribasim.run(toml_path)
     @test model isa Ribasim.Model
     @test successful_retcode(model)
-    @test model.integrator.sol.u[end] ≈ Float32[7.783636, 726.16394] skip = Sys.isapple()
+    @test model.integrator.u ≈ Float32[7.783636, 726.16394] skip = Sys.isapple()
     # the highest level in the dynamic table is updated to 1.2 from the callback
     @test model.integrator.p.tabulated_rating_curve.table[end].t[end] == 1.2
 end
@@ -471,8 +471,7 @@ end
     model = Ribasim.run(toml_path)
     @test successful_retcode(model)
 
-    u = model.integrator.sol.u[end]
-    p = model.integrator.p
+    (; u, p) = model.integrator
     h_actual = get_tmp(p.basin.current_level, u)[1:50]
     x = collect(10.0:20.0:990.0)
     h_expected = standard_step_method(x, 5.0, 1.0, 0.04, h_actual[end], 1.0e-6)