diff --git a/gir.js b/gir.js
index dddb751..a273922 100644
--- a/gir.js
+++ b/gir.js
@@ -241,17 +241,23 @@ function joinAdjacentOps(parsed) {
 				// Start of a possible run of commands
 				prevOfType = true;
 				value = command.value;
-			} else if(prevOfType && command.type != type) {
-				// A run has ended, add it to optimized
+			} else {
+				// If a run has ended, add it to optimized
 				// However, skip it if value is 0
-				if(value != 0) {
+				if(prevOfType && value != 0) {
 					optimized.push({type: type, value: value});
 				}
-				// Also add the command for this round
-				optimized.push(command);
-				prevOfType = false;
-			} else {
-				optimized.push(command);
+
+				// Add the command for this round
+				if(command.type == loop) {
+					// Recurse
+					optimized.push({type: loop,
+						contents: worker(
+							command.contents,
+							type)});
+				} else {
+					optimized.push(command);
+				}
 				prevOfType = false;
 			}
 		}
diff --git a/optimizations.md b/optimizations.md
index 8730442..28d4a77 100644
--- a/optimizations.md
+++ b/optimizations.md
@@ -6,6 +6,7 @@ joinAdjacentOps
 * *produces*: commands without offsets
 * *unknown commands*: passed through unmodified
 * *acts on*: `moveHead`, `add`
+* *other known commands*: `loop` (recurses)
 
 `joinAdjacentOps` joins adjacent `moveHead`s and `add`s together. Normally
 `parse` joins runs of `<>` or `+-` into one command, but if the runs are
@@ -19,6 +20,7 @@ transformClearLoops
 * *produces*: commands without offsets
 * *unknown commands*: passed through unmodified
 * *acts on*: `loop` with one command, which is `add 1` or `add -1`
+* *other known commands*: `loop` (recurses)
 
 `transformClearLoops` changes loops of the form `[-]` or `[+]` into a single
 `clear` command.