diff --git a/multigrid/src/main.rs b/multigrid/src/main.rs
index 252a4fc..6507f99 100644
--- a/multigrid/src/main.rs
+++ b/multigrid/src/main.rs
@@ -9,7 +9,6 @@ mod parsing;
 use file::*;
 mod eval;
 mod system;
-use system::*;
 
 #[derive(Debug, FromArgs)]
 /// Options for configuring and running the solver
@@ -77,35 +76,22 @@ fn main() {
     let parsing::RuntimeConfiguration {
         names,
         grids,
-        grid_connections,
+        boundary_conditions,
         op: operators,
         integration_time,
         initial_conditions,
-        boundary_conditions: _,
     } = config.into_runtime();
 
-    let mut sys = System::new(grids, grid_connections, operators);
-    match &initial_conditions {
-        /*
-        parsing::InitialConditions::File(f) => {
-            for grid in &sys.grids {
-                // Copy initial conditions from file, requires name of field
-                todo!()
-            }
-        }
-        */
-        parsing::InitialConditions::Vortex(vortexparams) => sys.vortex(0.0, &vortexparams),
-        parsing::InitialConditions::Expressions(expr) => {
-            let t = 0.0;
-            for (grid, field) in sys.grids.iter().zip(sys.fnow.iter_mut()) {
-                // Evaluate the expressions on all variables
-                let x = grid.x();
-                let y = grid.y();
-                let (rho, rhou, rhov, e) = field.components_mut();
-                (*expr).evaluate(t, x, y, rho, rhou, rhov, e);
-            }
-        }
-    }
+    let basesystem = system::BaseSystem::new(
+        names.clone(),
+        grids,
+        0.0,
+        operators,
+        boundary_conditions,
+        initial_conditions.clone(),
+    );
+    let mut sys = basesystem.create();
+    // System::new(grids, grid_connections, operators);
 
     let dt = sys.max_dt();
 
diff --git a/multigrid/src/parsing.rs b/multigrid/src/parsing.rs
index 5d87324..035ff70 100644
--- a/multigrid/src/parsing.rs
+++ b/multigrid/src/parsing.rs
@@ -27,7 +27,7 @@ pub enum InitialConditions {
 }
 
 #[derive(Clone, Debug)]
-pub enum BoundaryConditions {
+enum BoundaryConditions {
     Vortex(euler::VortexParameters),
     Expressions(std::sync::Arc<eval::Evaluator>),
     NotNeeded,
@@ -36,11 +36,10 @@ pub enum BoundaryConditions {
 pub struct RuntimeConfiguration {
     pub names: Vec<String>,
     pub grids: Vec<sbp::grid::Grid>,
-    pub grid_connections: Vec<euler::BoundaryCharacteristics>,
+    pub boundary_conditions: Vec<euler::BoundaryCharacteristics>,
     pub op: Vec<Box<dyn SbpOperator2d>>,
     pub integration_time: Float,
     pub initial_conditions: InitialConditions,
-    pub boundary_conditions: BoundaryConditions,
 }
 
 impl input::Configuration {
@@ -165,7 +164,7 @@ impl input::Configuration {
                 Box::new((matcher(eta), matcher(xi))) as Box<dyn SbpOperator2d>
             })
             .collect();
-        let grid_connections = self
+        let boundary_conditions = self
             .grids
             .iter()
             .map(|(name, g)| {
@@ -226,11 +225,10 @@ impl input::Configuration {
         RuntimeConfiguration {
             names,
             grids,
-            grid_connections,
+            boundary_conditions,
             op,
             integration_time: self.integration_time,
             initial_conditions,
-            boundary_conditions,
         }
     }
 }
diff --git a/multigrid/src/system.rs b/multigrid/src/system.rs
index 27ca5b4..034a7d8 100644
--- a/multigrid/src/system.rs
+++ b/multigrid/src/system.rs
@@ -1,3 +1,4 @@
+use crate::parsing;
 use crate::utils::Direction;
 use crossbeam_channel::{Receiver, Select, Sender};
 use euler::{
@@ -10,6 +11,60 @@ use sbp::operators::{InterpolationOperator, SbpOperator2d};
 use sbp::*;
 use std::sync::{Arc, Barrier};
 
+pub struct BaseSystem {
+    pub names: Vec<String>,
+    pub grids: Vec<grid::Grid>,
+    pub time: Float,
+    pub boundary_conditions: Vec<euler::BoundaryCharacteristics>,
+    pub initial_conditions: crate::parsing::InitialConditions,
+    pub operators: Vec<Box<dyn SbpOperator2d>>,
+}
+
+impl BaseSystem {
+    pub fn new(
+        names: Vec<String>,
+        grids: Vec<grid::Grid>,
+        time: Float,
+        operators: Vec<Box<dyn SbpOperator2d>>,
+        boundary_conditions: Vec<euler::BoundaryCharacteristics>,
+        initial_conditions: crate::parsing::InitialConditions,
+    ) -> Self {
+        Self {
+            names,
+            grids,
+            time,
+            boundary_conditions,
+            initial_conditions,
+            operators,
+        }
+    }
+    pub fn create(self) -> System {
+        let mut sys = System::new(self.grids, self.boundary_conditions, self.operators);
+        match &self.initial_conditions {
+            /*
+            parsing::InitialConditions::File(f) => {
+                for grid in &sys.grids {
+                    // Copy initial conditions from file, requires name of field
+                    todo!()
+                }
+            }
+            */
+            parsing::InitialConditions::Vortex(vortexparams) => sys.vortex(0.0, &vortexparams),
+            parsing::InitialConditions::Expressions(expr) => {
+                let t = 0.0;
+                for (grid, field) in sys.grids.iter().zip(sys.fnow.iter_mut()) {
+                    // Evaluate the expressions on all variables
+                    let x = grid.x();
+                    let y = grid.y();
+                    let (rho, rhou, rhov, e) = field.components_mut();
+                    (*expr).evaluate(t, x, y, rho, rhou, rhov, e);
+                }
+            }
+        }
+        sys
+    }
+}
+
 pub struct System {
     pub fnow: Vec<euler::Field>,
     pub fnext: Vec<euler::Field>,