diff --git a/src/engine/functions/index.ts b/src/engine/functions/index.ts
index 88923f6..59e3f89 100644
--- a/src/engine/functions/index.ts
+++ b/src/engine/functions/index.ts
@@ -16,7 +16,6 @@ export type BehaviourLink = {
 }
 
 export type BehaviourInput = BehaviourResourcePin & {
-    rate: number; // per second of tick deltaTime
     link: BehaviourLink;
 }
 
@@ -25,7 +24,6 @@ export type BehaviourInputs = {
 }
 
 export type BehaviourOutput = BehaviourResourcePin & {
-    rate: number; // per second of tick deltaTime
 }
 
 export type BehaviourOutputs = {
@@ -51,13 +49,11 @@ export abstract class Behaviour {
         this.outputs = {
             pins: source.outputs.pins.map((output) => ({
                 resource: output.resource,
-                rate: output.rate,
             })),
         }
         this.inputs = {
             pins: source.inputs.pins.map((input) => ({
                 resource: input.resource,
-                rate: input.rate,
                 link: input.link,
             })),
         }
@@ -71,7 +67,7 @@ export abstract class Behaviour {
     abstract getDisplayInfo(): BehaviourDisplayInfo;
 
     /** Withdraws up to `amount` of `resource` from this behaviour's storage, returning how much was actually taken. */
-    protected take(resource: Resource, amount: number): number {
+    public take(resource: Resource, amount: number): number {
         const available = this.storage[resource] ?? 0;
         const taken = Math.min(available, amount);
         this.storage[resource] = available - taken;
@@ -82,30 +78,46 @@ export abstract class Behaviour {
         this.storage[resource] = (this.storage[resource] ?? 0) + amount;
     }
 
-    /** Fills this behaviour's own storage from its outputs' production rates. */
-    public produce(deltaTime: number): void {
-        for (const output of this.outputs.pins)
-            this.give(output.resource, output.rate * deltaTime);
+    abstract produce(deltaTime: number): void;
+
+    abstract pull(deltaTime: number, resolve: (id: string) => Behaviour | undefined): void;
+}
+
+export class Converter extends Behaviour {
+    public readonly inputRates: Partial<Resources>;
+    public readonly outputRates: Partial<Resources>;
+
+    constructor(source: SerializedNodeBehaviour & SerializedConverter) {
+        if (source.kind !== 'converter')
+            throw new Error('Invalid source');
+        super(source);
+
+        this.inputRates = {};
+        for (const pin of source.inputs.pins)
+            this.inputRates[pin.resource] = pin.rate;
+
+        this.outputRates = {};
+        for (const pin of source.outputs.pins)
+            this.outputRates[pin.resource] = pin.rate;
     }
 
-    /** Pulls resources into this behaviour's storage from whatever each input pin is linked to. */
+    /** Fills this converter's own storage from its outputs' production rates. */
+    public produce(deltaTime: number): void {
+        for (const output of this.outputs.pins)
+            this.give(output.resource, (this.outputRates[output.resource] ?? 0) * deltaTime);
+    }
+
+    /** Pulls resources into this converter's storage from whatever each input pin is linked to. */
     public pull(deltaTime: number, resolve: (id: string) => Behaviour | undefined): void {
         for (const input of this.inputs.pins) {
             const source = resolve(input.link.target);
             if (!source)
                 continue;
-            const taken = source.take(input.link.resource, input.rate * deltaTime);
+            const rate = this.inputRates[input.resource] ?? 0;
+            const taken = source.take(input.link.resource, rate * deltaTime);
             this.give(input.resource, taken);
         }
     }
-}
-
-export class Converter extends Behaviour {
-    constructor(source: SerializedNodeBehaviour & SerializedConverter) {
-        if (source.kind !== 'converter')
-            throw new Error('Invalid source');
-        super(source);
-    }
 
     public getDisplayInfo(): BehaviourDisplayInfo {
         return {
diff --git a/src/engine/saveLoad.ts b/src/engine/saveLoad.ts
index 9a0639d..b9fd064 100644
--- a/src/engine/saveLoad.ts
+++ b/src/engine/saveLoad.ts
@@ -1,20 +1,28 @@
 import { defaultGame } from "../prefabs/game";
 import { Game, SerializedGame, SerializedNodeBehaviour } from "../types";
-import { Behaviour, behaviours } from "./functions";
+import { Behaviour, behaviours, Converter } from "./functions";
 
 export function serializeBehaviour(behaviour: Behaviour): SerializedNodeBehaviour {
     switch (behaviour.kind) {
-        case 'converter':
+        case 'converter': {
+            const converter = behaviour as Converter;
             return {
-                id: behaviour.id,
+                id: converter.id,
                 kind: 'converter',
                 inputs: {
-                    pins: behaviour.inputs.pins.map((pin) => ({ ...pin })),
+                    pins: converter.inputs.pins.map((pin) => ({
+                        ...pin,
+                        rate: converter.inputRates[pin.resource] ?? 0,
+                    })),
                 },
                 outputs: {
-                    pins: behaviour.outputs.pins.map((pin) => ({ ...pin })),
+                    pins: converter.outputs.pins.map((pin) => ({
+                        ...pin,
+                        rate: converter.outputRates[pin.resource] ?? 0,
+                    })),
                 },
             };
+        }
         default:
             throw new Error('Unknown behaviour');
     }