diff --git a/Cavern/Utilities/Interfaces/ILongProcess.cs b/Cavern/Utilities/Interfaces/ILongProcess.cs
new file mode 100644
index 00000000..40db743b
--- /dev/null
+++ b/Cavern/Utilities/Interfaces/ILongProcess.cs
@@ -0,0 +1,11 @@
+namespace Cavern.Utilities {
+    /// <summary>
+    /// An operation that takes a long time and should run in the background. Its interface provides progress polling.
+    /// </summary>
+    public interface ILongProcess {
+        /// <summary>
+        /// The ratio of doneness [0;1].
+        /// </summary>
+        float Progress { get; }
+    }
+}
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