This works for me in a linux/bsd environment:
I have a vendor directory which holds all the tar.gz's from cpan, and a makefile
Makefile:

PWD = $(shell pwd)
CACHE_DIR ?= cache
PERL = $(shell which perl)
BUILD_INCS = -I $(PWD)/$(CACHE_DIR)/lib/perl5
INSTALL_TARGET ?= $(PWD)/$(CACHE_DIR)
MAKEFILE_PL_ARGS = INSTALL_BASE=$(INSTALL_TARGET) PERL="$(PERL) $(BUIL
+D_INCS)"

TGZFILES = $(wildcard *.tar.gz)
DEPENDS_ORDER2 = $(shell cat install_order) $(TGZFILES)
# remove duplicates
DEPENDS_ORDER = $(shell perl -e '@b=grep{!$$s{$$_}++} @ARGV;print "@b"
+' $(DEPENDS_ORDER2))

# this gets a list of all the directories that the .tar.gz files unpac
+k into
UNPACK_DIRS = $(shell for t in $(DEPENDS_ORDER);do for f in `tar tzf $
+$t`;do R="$$R $$f/";break;done;done;echo $$R)
BLIBS       = $(patsubst %/,%/blib,$(UNPACK_DIRS))

# we want to link to gmake here, unless it is not available
GMAKE = $(firstword $(shell which gmake) $(shell which $(MAKE)) )

PATH = $(PWD)/bin:$(shell echo $$PATH)

.PHONY: all clean install $(TGZFILES)

all:
    @ echo -------------------------------------------
    @ echo "TGZFILES: $(TGZFILES)"
    @ echo -------------------------------------------
    @ echo "DEPENDS_ORDER: $(DEPENDS_ORDER)"
    @ echo -------------------------------------------
    @ echo "UNPACK_DIRS: $(UNPACK_DIRS)"
    @ echo -------------------------------------------
    @ echo "BLIBS: $(BLIBS)"
    @ echo -------------------------------------------
    @ echo "BUILD_INCS: $(BUILD_INCS)"
    @ echo -------------------------------------------

$(UNPACK_DIRS):
    @ echo unpacking $@
    @ echo -n "  "
    tar xfz $(@).tar.gz
    @ for patch_file in patches/*.$(@).tar.gz.*.patch; do \
        if [ ! -e $$patch_file ]; then \
            echo "  No patches found for $(@).tar.gz"; \
            continue; \
        fi; \
        echo "  Running patch $$patch_file: "; \
        patch -p1 < $$patch_file; \
    done;

    @ echo "  Making makefile $@ in $@";
    @ cd $@ && TipTop=1 PERL_MM_USE_DEFAULT=1 perl $(BUILD_INCS) Makef
+ile.PL $(MAKEFILE_PL_ARGS) >> build.log;

    @ echo "  Making blib $@ in $@";
    @ $(MAKE) -C $@ all >>build.log
# ARCH=1 is to override BSDPAN (hateful software)
    @ echo "  Installing $(@) into $(INSTALL_TARGET)"
    @ $(MAKE) -C $@ pure_install ARCH=1 >> build.log

# force the use of gmake by putting it first in the path
ENV:
    rm -rf bin/make
    ln -sf $(GMAKE) bin/make

$(CACHE_DIR): ENV $(UNPACK_DIRS)

install: $(CACHE_DIR)
    @ echo "Copying $(CACHE_DIR) to $(TARGET)";
    mkdir -p $(TARGET)/
    cp -Rf $(CACHE_DIR)/lib/perl5/* $(TARGET)/
    @ touch $(CACHE_DIR)

clean:
    rm -rf $(UNPACK_DIRS)
    rm -rf $(CACHE_DIR)
    rm -f ./build.log
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I can pretty much just add modules to the vendor directory and it picks it up.

Some modules depend on others so there is an 'install_order' file that lists the order those modules should be installed.

I also have a patches directory in case I need to patch the cpan modules before they get built.

I call this from my main makefile like this:

$(MAKE) -C $(VENDOR_DIR) install TARGET=$(LOCAL_BUILD_TARGET)/lib/
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