diff --git a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/generic/GenericPeripheral.java b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/generic/GenericPeripheral.java
index d57208b8f..ee4f1f299 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/generic/GenericPeripheral.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/generic/GenericPeripheral.java
@@ -11,6 +11,7 @@ import dan200.computercraft.api.lua.MethodResult;
 import dan200.computercraft.api.peripheral.IComputerAccess;
 import dan200.computercraft.api.peripheral.IDynamicPeripheral;
 import dan200.computercraft.api.peripheral.IPeripheral;
+import dan200.computercraft.core.computer.GuardedLuaContext;
 import net.minecraft.core.Direction;
 import net.minecraft.world.level.block.entity.BlockEntity;
 
@@ -26,12 +27,16 @@ public final class GenericPeripheral implements IDynamicPeripheral {
     private final Set<String> additionalTypes;
     private final List<SaturatedMethod> methods;
 
+    private @Nullable GuardedLuaContext contextWrapper;
+    private final GuardedLuaContext.Guard guard;
+
     GenericPeripheral(BlockEntity tile, Direction side, String type, Set<String> additionalTypes, List<SaturatedMethod> methods) {
         this.side = side;
         this.tile = tile;
         this.type = type;
         this.additionalTypes = additionalTypes;
         this.methods = methods;
+        this.guard = () -> !tile.isRemoved() && tile.getLevel() != null && tile.getLevel().isLoaded(tile.getBlockPos());
     }
 
     public Direction side() {
@@ -47,7 +52,12 @@ public final class GenericPeripheral implements IDynamicPeripheral {
 
     @Override
     public MethodResult callMethod(IComputerAccess computer, ILuaContext context, int method, IArguments arguments) throws LuaException {
-        return methods.get(method).apply(context, computer, arguments);
+        var contextWrapper = this.contextWrapper;
+        if (contextWrapper == null || !contextWrapper.wraps(context)) {
+            contextWrapper = this.contextWrapper = new GuardedLuaContext(context, guard);
+        }
+
+        return methods.get(method).apply(contextWrapper, computer, arguments);
     }
 
     @Override
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemPeripheral.java b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemPeripheral.java
index ac14bd962..ce1374b27 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemPeripheral.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/peripheral/modem/wired/WiredModemPeripheral.java
@@ -15,6 +15,7 @@ import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.api.peripheral.NotAttachedException;
 import dan200.computercraft.api.peripheral.WorkMonitor;
 import dan200.computercraft.core.apis.PeripheralAPI;
+import dan200.computercraft.core.computer.GuardedLuaContext;
 import dan200.computercraft.core.methods.PeripheralMethod;
 import dan200.computercraft.core.util.LuaUtil;
 import dan200.computercraft.shared.computer.core.ServerContext;
@@ -304,7 +305,7 @@ public abstract class WiredModemPeripheral extends ModemPeripheral implements Wi
         return wrappers == null ? null : wrappers.get(remoteName);
     }
 
-    private static class RemotePeripheralWrapper implements IComputerAccess {
+    private static class RemotePeripheralWrapper implements IComputerAccess, GuardedLuaContext.Guard {
         private final WiredModemElement element;
         private final IPeripheral peripheral;
         private final IComputerAccess computer;
@@ -317,6 +318,8 @@ public abstract class WiredModemPeripheral extends ModemPeripheral implements Wi
         private volatile boolean attached;
         private final Set<String> mounts = new HashSet<>();
 
+        private @Nullable GuardedLuaContext contextWrapper;
+
         RemotePeripheralWrapper(WiredModemElement element, IPeripheral peripheral, IComputerAccess computer, String name, Map<String, PeripheralMethod> methods) {
             this.element = element;
             this.peripheral = peripheral;
@@ -364,7 +367,19 @@ public abstract class WiredModemPeripheral extends ModemPeripheral implements Wi
         public MethodResult callMethod(ILuaContext context, String methodName, IArguments arguments) throws LuaException {
             var method = methodMap.get(methodName);
             if (method == null) throw new LuaException("No such method " + methodName);
-            return method.apply(peripheral, context, this, arguments);
+
+            // Wrap the ILuaContext. We try to reuse the previous context where possible to avoid allocations.
+            var contextWrapper = this.contextWrapper;
+            if (contextWrapper == null || !contextWrapper.wraps(context)) {
+                contextWrapper = this.contextWrapper = new GuardedLuaContext(context, this);
+            }
+
+            return method.apply(peripheral, contextWrapper, this, arguments);
+        }
+
+        @Override
+        public boolean checkValid() {
+            return attached;
         }
 
         // IComputerAccess implementation
diff --git a/projects/core/src/main/java/dan200/computercraft/core/apis/PeripheralAPI.java b/projects/core/src/main/java/dan200/computercraft/core/apis/PeripheralAPI.java
index 70fdb0b1c..0b5307fcd 100644
--- a/projects/core/src/main/java/dan200/computercraft/core/apis/PeripheralAPI.java
+++ b/projects/core/src/main/java/dan200/computercraft/core/apis/PeripheralAPI.java
@@ -11,6 +11,7 @@ import dan200.computercraft.api.peripheral.IPeripheral;
 import dan200.computercraft.api.peripheral.NotAttachedException;
 import dan200.computercraft.api.peripheral.WorkMonitor;
 import dan200.computercraft.core.computer.ComputerSide;
+import dan200.computercraft.core.computer.GuardedLuaContext;
 import dan200.computercraft.core.methods.MethodSupplier;
 import dan200.computercraft.core.methods.PeripheralMethod;
 import dan200.computercraft.core.metrics.Metrics;
@@ -26,7 +27,7 @@ import java.util.*;
  * @hidden
  */
 public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChangeListener {
-    private class PeripheralWrapper extends ComputerAccess {
+    private class PeripheralWrapper extends ComputerAccess implements GuardedLuaContext.Guard {
         private final String side;
         private final IPeripheral peripheral;
 
@@ -35,6 +36,8 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
         private final Map<String, PeripheralMethod> methodMap;
         private boolean attached = false;
 
+        private @Nullable GuardedLuaContext contextWrapper;
+
         PeripheralWrapper(IPeripheral peripheral, String side) {
             super(environment);
             this.side = side;
@@ -91,9 +94,21 @@ public class PeripheralAPI implements ILuaAPI, IAPIEnvironment.IPeripheralChange
 
             if (method == null) throw new LuaException("No such method " + methodName);
 
-            try (var ignored = environment.time(Metrics.PERIPHERAL_OPS)) {
-                return method.apply(peripheral, context, this, arguments);
+            // Wrap the ILuaContext. We try to reuse the previous context where possible to avoid allocations - this
+            // should be pretty common as ILuaMachine uses a constant context.
+            var contextWrapper = this.contextWrapper;
+            if (contextWrapper == null || !contextWrapper.wraps(context)) {
+                contextWrapper = this.contextWrapper = new GuardedLuaContext(context, this);
             }
+
+            try (var ignored = environment.time(Metrics.PERIPHERAL_OPS)) {
+                return method.apply(peripheral, contextWrapper, this, arguments);
+            }
+        }
+
+        @Override
+        public boolean checkValid() {
+            return isAttached();
         }
 
         // IComputerAccess implementation
diff --git a/projects/core/src/main/java/dan200/computercraft/core/computer/GuardedLuaContext.java b/projects/core/src/main/java/dan200/computercraft/core/computer/GuardedLuaContext.java
new file mode 100644
index 000000000..06dc65235
--- /dev/null
+++ b/projects/core/src/main/java/dan200/computercraft/core/computer/GuardedLuaContext.java
@@ -0,0 +1,55 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.core.computer;
+
+import dan200.computercraft.api.lua.ILuaContext;
+import dan200.computercraft.api.lua.LuaException;
+import dan200.computercraft.api.lua.LuaTask;
+
+/**
+ * A {@link ILuaContext} which checks if context is valid when before executing
+ * {@linkplain #issueMainThreadTask(LuaTask) main-thread tasks}.
+ */
+public final class GuardedLuaContext implements ILuaContext {
+    private final ILuaContext original;
+    private final Guard guard;
+
+    public GuardedLuaContext(ILuaContext original, Guard guard) {
+        this.original = original;
+        this.guard = guard;
+    }
+
+    /**
+     * Determine if this {@link GuardedLuaContext} wraps another context.
+     * <p>
+     * This may be used to avoid constructing new guarded contexts, in a pattern something like:
+     *
+     * <pre>{@code
+     * var contextWrapper = this.contextWrapper;
+     * if(contextWrapper == null || !contextWrapper.wraps(context)) {
+     *     contextWrapper = this.contextWrapper = new GuardedLuaContext(context, this);
+     * }
+     * }</pre>
+     *
+     * @param context The original context.
+     * @return Whether {@code this} wraps {@code context}.
+     */
+    public boolean wraps(ILuaContext context) {
+        return original == context;
+    }
+
+    @Override
+    public long issueMainThreadTask(LuaTask task) throws LuaException {
+        return original.issueMainThreadTask(() -> guard.checkValid() ? task.execute() : null);
+    }
+
+    /**
+     * The function which checks if the context is still valid.
+     */
+    @FunctionalInterface
+    public interface Guard {
+        boolean checkValid();
+    }
+}