diff --git a/native/include/m_driver.h b/native/include/m_driver.h
index 8ae042d0..11b4693d 100644
--- a/native/include/m_driver.h
+++ b/native/include/m_driver.h
@@ -2,6 +2,7 @@
 #include<iostream>
 #include "c_micro_sim.h"
 
+class Integrator;  // forward declaration
 // Base class for the drivers
 class Driver {
 public:
@@ -13,15 +14,37 @@ class Driver {
     double * alpha;
     double gamma;
     double t;
+    MicroSim * sim;
+    Integrator * integrator;
+
+    virtual void run_until(double t) {};
 };
 
 
-class Integrator_RK4 {
+// Abstract class
+class Integrator {
+public:
+    Integrator() {};
+    virtual void _setup(int N) {};
+    // Allow magnetisation to update (via LLG + effective field) 
+    // TODO: figure out how to set the update function in Driver class
+    virtual void compute_RHS(void (* f) (double * m, double t)) {};
+}
+
+// Integrators should be independent of any driver/sim class
+class Integrator_RK4: public Integrator {
 public:
     Integrator_RK4() {};
     virtual ~Integrator_RK4() {std::cout << "Killing RK4 integrator\n";};
     // Will get the parameters from a simulation class
     // void _setup(MicroSim * sim, Driver * driver);
-    std::vector<double> rk_steps;  // N * 4 array
-    void integration_step(double (*f)(double t, double y));
+    std::vector<double> rk1;  // N array
+    std::vector<double> rk2;  // N array
+    std::vector<double> rk3;  // N array
+    std::vector<double> rk4;  // N array
+    void integration_step(double (*f)(double t, double m));  // compute_RHS ??
+    void _setup(int N);
+    int N;
+    double t;
+    double dt;
 };
diff --git a/native/src/m_driver.c b/native/src/m_driver.c
new file mode 100644
index 00000000..ef323bfa
--- /dev/null
+++ b/native/src/m_driver.c
@@ -0,0 +1,5 @@
+#include "m_driver.h"
+
+void Integrator_RK4::_setup(int N) {
+    this->rk_steps(N * 4, 0.0);
+}