diff --git a/Makefile b/Makefile
index 2656672..ca4dc6a 100644
--- a/Makefile
+++ b/Makefile
@@ -17,6 +17,11 @@ EMU_SRC_FILES := $(wildcard src/emulated/*.c)
 EMU_OBJ_FILES := $(EMU_SRC_FILES:src/emulated/%.c=build/%.riscv.o)
 EMU_OBJ := build/emulated.riscv.elf
 EMU_OBJ_LICENSE := build/license
+EMU_OBJ_LICENSE_IF_EXISTS := $(wildcard $(EMU_OBJ_LICENSE))
+
+ZIP_FILE := build/challenge.zip
+ZIP_FILE_IF_EXISTS := $(wildcard $(ZIP_FILE))
+
 
 GENERATED := build/include/generated.h
 
@@ -47,33 +52,44 @@ _DISAS_FILES   := $(if $(_DISAS_TARGETS),$(filter %.elf %.o,$(MAKECMDGOALS)))
 
 .PHONY: all emulated-riscv host clean disas-risc
 
-all: $(HOST_EXE) $(EMU_OBJ_LICENSE) $(HOST_EXE_ENCRYPTOR)
+all: $(ZIP_FILE)
 
 emulated-riscv: $(EMU_OBJ_LICENSE)
 
-host: $(HOST_EXE) $(HOST_EXE_ENCRYPTOR)
+host: $(HOST_EXE)
 
+# Build the main challenge executable
 $(HOST_EXE): $(HOST_SRC) | build
 	$(HOST_CC) $(HOST_CFLAGS) $(HOST_LDFLAGS) $(HOST_INCLUDE) $(HOST_SRC) -o $@
 
+# Build the encryptor
 $(HOST_EXE_ENCRYPTOR): $(HOST_SRC_ENCRYPTOR) | build
 	$(HOST_CC) $(HOST_CFLAGS) $(HOST_LDFLAGS) $(HOST_INCLUDE) $(HOST_SRC_ENCRYPTOR) -o $@
 
-build/%.riscv.o: src/emulated/%.c $(GENERATED) $(HOST_EXE_ENCRYPTOR) | build
-	$(RISCV_CC) $(RISCV_ARCH_FLAGS) -I $(dir $(GENERATED)) -I src/emulated -c $< -o $@
+# Build emulated object files
+$(EMU_OBJ_FILES): $(EMU_SRC_FILES) $(GENERATED) | build
+	$(RISCV_CC) $(RISCV_ARCH_FLAGS) -I $(dir $(GENERATED)) -I src/emulated -c $(EMU_SRC_FILES) -o $@
 
 
-EMU_OBJ_LICENSE_IF_EXISTS := $(wildcard $(EMU_OBJ_LICENSE))
-$(EMU_OBJ_LICENSE): $(EMU_OBJ) | build
+# Encrypt license file
+$(EMU_OBJ_LICENSE): $(EMU_OBJ) $(HOST_EXE_ENCRYPTOR) | build
 ifneq ($(EMU_OBJ_LICENSE_IF_EXISTS),)
 	rm $(EMU_OBJ_LICENSE_IF_EXISTS)
 endif
 	$(HOST_EXE_ENCRYPTOR) $(EMU_OBJ) $@
 
+# Build (unencrypted) license file
 $(EMU_OBJ): $(EMU_OBJ_FILES) | build
 	$(RISCV_CC) $(RISCV_ARCH_FLAGS) -nostdlib -Wl,-e,entry -Wl,-Ttext=0 -Wl,--emit-relocs $(EMU_OBJ_FILES) -o $@
 
 
+# Bundle the challenge
+$(ZIP_FILE): $(HOST_EXE) $(EMU_OBJ_LICENSE) | build
+ifneq ($(ZIP_FILE_IF_EXISTS),)
+	rm $(ZIP_FILE_IF_EXISTS)
+endif
+	cd build && 7z a -bso0 $(CURDIR)/$@ $(notdir $^)
+
 .FORCE:
 
 $(GENERATED): .FORCE