diff --git a/Programs/CosmOS/README.md b/Programs/CosmOS/README.md
index 71b32c0..86e5043 100644
--- a/Programs/CosmOS/README.md
+++ b/Programs/CosmOS/README.md
@@ -75,6 +75,18 @@ To boot CosmOS with that disk attached:
 make run-cosmos
 ```
 
+Or on the Voyager, which is the same machine with a screen and a speaker instead of a
+terminal:
+
+```sh
+make run-voyager
+```
+
+Both depend on the disk rather than merely using it, which is worth knowing: **what is on a
+disk is whatever was built when the disk was made.** A machine whose console has changed
+will start an old image quite happily and its programs will draw whatever the old way now
+means, which is a confusing thing to debug and an easy thing to avoid.
+
 The generated files are kept under `Programs/build/`:
 
 - `CosmOS/Source/cosmos.bin` is the bootable CosmOS image.
diff --git a/Programs/makefile b/Programs/makefile
index 942c0ea..570d7f9 100644
--- a/Programs/makefile
+++ b/Programs/makefile
@@ -69,6 +69,7 @@ run-%:
 #   make cosmos       Assemble the system and everything it can load.
 #   make cosmos-disk  ... and put the loadable programs on a disk image.
 #   make run-cosmos   ... and boot the machine with that disk in the drive.
+#   make run-voyager  ... and boot the machine that has a screen instead of a terminal.
 #
 # Programs in Apps/ say where they live with #Base, so the assembler writes them out as
 # loadable programs rather than as boot images. They are named .sbx to keep that
@@ -220,6 +221,22 @@ run-cosmos: $(COSMOS_DISK)
 run-cosmos-direct: $(COSMOS) $(COSMOS_DISK)
 	$(EMU) --disk $(COSMOS_DISK) $(COSMOS)
 
+# ---- The same disk, on the machine with a screen ----
+#
+# Voyager rather than SplitBit, which is the only difference: same disk, same system, same
+# programs, presented through a window instead of a terminal.
+#
+# IT DEPENDS ON THE DISK, and that matters more than it looks. What is on a disk is whatever
+# was built when the disk was made, so a machine whose console has changed will happily boot
+# an image full of programs written for the old one - and they will draw whatever the old
+# way now means. Making the disk a dependency of running it is what stops that being a
+# puzzle.
+run-voyager: $(COSMOS_DISK)
+	../Voyager --disk $(COSMOS_DISK)
+
+run-voyager-direct: $(COSMOS) $(COSMOS_DISK)
+	../Voyager --disk $(COSMOS_DISK) $(COSMOS)
+
 clean:
 	rm -rf $(BUILD)
 
@@ -227,4 +244,4 @@ clean:
 # reassembles every program that includes it.
 -include $(DEPENDENCIES)
 
-.PHONY: all clean cosmos cosmos-disk run-cosmos run-cosmos-direct
+.PHONY: all clean cosmos cosmos-disk run-cosmos run-cosmos-direct run-voyager run-voyager-direct
diff --git a/README.md b/README.md
index 709dedf..da64816 100644
--- a/README.md
+++ b/README.md
@@ -104,6 +104,12 @@ make run-cosmos
 
 Then `dir` to see what is there, `load Snake.sbx` and `run` to play something, or `load Asm.sbx` and `run cosmos.asm` to watch the machine build itself.
 
+`make run-voyager` boots the same disk on the machine with a screen instead of a terminal.
+Both targets depend on the disk, so a disk built before a change to the machine is rebuilt
+rather than booted as it stands: **what is on a disk is whatever was built when the disk was
+made**, and a system whose console has changed will happily start an image full of programs
+written for the old one.
+
 ## Running Programs: SplitBit
 
 ```