diff --git a/repos/os/lib/mk/sd_card.inc b/repos/os/lib/mk/sd_card.inc
new file mode 100644
index 000000000..0eb4701d4
--- /dev/null
+++ b/repos/os/lib/mk/sd_card.inc
@@ -0,0 +1,6 @@
+
+INC_DIR += $(REP_DIR)/src/drivers/sd_card
+
+LIBS += base
+
+vpath %.cc $(REP_DIR)/src/drivers/sd_card
diff --git a/repos/os/lib/mk/sd_card_bench.inc b/repos/os/lib/mk/sd_card_bench.inc
new file mode 100644
index 000000000..d022dbdb1
--- /dev/null
+++ b/repos/os/lib/mk/sd_card_bench.inc
@@ -0,0 +1,4 @@
+SRC_CC += main.cc
+LIBS   += server
+vpath main.cc $(REP_DIR)/src/test/sd_card_bench
+include $(REP_DIR)/lib/mk/sd_card.inc
diff --git a/repos/os/lib/mk/spec/exynos5/sd_card_bench.mk b/repos/os/lib/mk/spec/exynos5/sd_card_bench.mk
new file mode 100644
index 000000000..ad5e7d164
--- /dev/null
+++ b/repos/os/lib/mk/spec/exynos5/sd_card_bench.mk
@@ -0,0 +1,2 @@
+INC_DIR += $(REP_DIR)/src/drivers/sd_card/spec/exynos5
+include $(REP_DIR)/lib/mk/sd_card_bench.inc
diff --git a/repos/os/lib/mk/spec/exynos5/sd_card_drv.mk b/repos/os/lib/mk/spec/exynos5/sd_card_drv.mk
new file mode 100644
index 000000000..250a98352
--- /dev/null
+++ b/repos/os/lib/mk/spec/exynos5/sd_card_drv.mk
@@ -0,0 +1,3 @@
+SRC_CC  += spec/exynos5/main.cc
+INC_DIR += $(REP_DIR)/src/drivers/sd_card/spec/exynos5
+include $(REP_DIR)/lib/mk/sd_card.inc
diff --git a/repos/os/lib/mk/spec/imx53/sd_card_bench.mk b/repos/os/lib/mk/spec/imx53/sd_card_bench.mk
new file mode 100644
index 000000000..5cedf62a3
--- /dev/null
+++ b/repos/os/lib/mk/spec/imx53/sd_card_bench.mk
@@ -0,0 +1,4 @@
+INC_DIR += $(REP_DIR)/src/drivers/sd_card/spec/imx53
+SRC_CC  += spec/imx53/adma2.cc
+SRC_CC  += spec/imx53/esdhcv2.cc
+include $(REP_DIR)/lib/mk/sd_card_bench.inc
diff --git a/repos/os/lib/mk/spec/imx53/sd_card_drv.mk b/repos/os/lib/mk/spec/imx53/sd_card_drv.mk
new file mode 100644
index 000000000..e42f8b2ff
--- /dev/null
+++ b/repos/os/lib/mk/spec/imx53/sd_card_drv.mk
@@ -0,0 +1,5 @@
+INC_DIR += $(REP_DIR)/src/drivers/sd_card/spec/imx53
+SRC_CC  += spec/imx53/adma2.cc
+SRC_CC  += spec/imx53/esdhcv2.cc
+SRC_CC  += spec/imx53/main.cc
+include $(REP_DIR)/lib/mk/sd_card.inc
diff --git a/repos/os/lib/mk/spec/omap4/sd_card_bench.mk b/repos/os/lib/mk/spec/omap4/sd_card_bench.mk
new file mode 100644
index 000000000..4ed3bd538
--- /dev/null
+++ b/repos/os/lib/mk/spec/omap4/sd_card_bench.mk
@@ -0,0 +1,2 @@
+INC_DIR += $(REP_DIR)/src/drivers/sd_card/spec/omap4
+include $(REP_DIR)/lib/mk/sd_card_bench.inc
diff --git a/repos/os/lib/mk/spec/omap4/sd_card_drv.mk b/repos/os/lib/mk/spec/omap4/sd_card_drv.mk
new file mode 100644
index 000000000..06883a0a1
--- /dev/null
+++ b/repos/os/lib/mk/spec/omap4/sd_card_drv.mk
@@ -0,0 +1,3 @@
+SRC_CC  += spec/omap4/main.cc
+INC_DIR += $(REP_DIR)/src/drivers/sd_card/spec/omap4
+include $(REP_DIR)/lib/mk/sd_card.inc
diff --git a/repos/os/lib/mk/spec/pl180/sd_card_drv.mk b/repos/os/lib/mk/spec/pl180/sd_card_drv.mk
new file mode 100644
index 000000000..6261acfbf
--- /dev/null
+++ b/repos/os/lib/mk/spec/pl180/sd_card_drv.mk
@@ -0,0 +1,3 @@
+SRC_CC  += spec/pl180/main.cc
+INC_DIR += $(REP_DIR)/src/drivers/sd_card/spec/pl180
+include $(REP_DIR)/lib/mk/sd_card.inc
diff --git a/repos/os/lib/mk/spec/rpi/sd_card_bench.mk b/repos/os/lib/mk/spec/rpi/sd_card_bench.mk
new file mode 100644
index 000000000..bbe27567d
--- /dev/null
+++ b/repos/os/lib/mk/spec/rpi/sd_card_bench.mk
@@ -0,0 +1,2 @@
+INC_DIR += $(REP_DIR)/src/drivers/sd_card/spec/rpi
+include $(REP_DIR)/lib/mk/sd_card_bench.inc
diff --git a/repos/os/lib/mk/spec/rpi/sd_card_drv.mk b/repos/os/lib/mk/spec/rpi/sd_card_drv.mk
new file mode 100644
index 000000000..bed1918da
--- /dev/null
+++ b/repos/os/lib/mk/spec/rpi/sd_card_drv.mk
@@ -0,0 +1,3 @@
+SRC_CC  += spec/rpi/main.cc
+INC_DIR += $(REP_DIR)/src/drivers/sd_card/spec/rpi
+include $(REP_DIR)/lib/mk/sd_card.inc
diff --git a/repos/os/src/drivers/sd_card/empty.cc b/repos/os/src/drivers/sd_card/empty.cc
new file mode 100644
index 000000000..066c1bf82
--- /dev/null
+++ b/repos/os/src/drivers/sd_card/empty.cc
@@ -0,0 +1,3 @@
+/*
+ * Dummy compilation unit needed to link a valid target.
+ */
diff --git a/repos/os/src/drivers/sd_card/spec/exynos5/target.mk b/repos/os/src/drivers/sd_card/spec/exynos5/target.mk
deleted file mode 100644
index 09d947520..000000000
--- a/repos/os/src/drivers/sd_card/spec/exynos5/target.mk
+++ /dev/null
@@ -1,5 +0,0 @@
-TARGET   = sd_card_drv
-REQUIRES = exynos5
-SRC_CC   = main.cc
-LIBS     = base
-INC_DIR += $(PRG_DIR) $(REP_DIR)/src/drivers/sd_card
diff --git a/repos/os/src/drivers/sd_card/spec/imx53/bench/target.mk b/repos/os/src/drivers/sd_card/spec/imx53/bench/target.mk
deleted file mode 100644
index b465d5e75..000000000
--- a/repos/os/src/drivers/sd_card/spec/imx53/bench/target.mk
+++ /dev/null
@@ -1,9 +0,0 @@
-TARGET    = sd_card_bench
-REQUIRES += imx53
-SRC_CC   += main.cc
-SRC_CC   += ../adma2.cc
-SRC_CC   += ../esdhcv2.cc
-LIBS     += base
-LIBS     += server
-INC_DIR  += $(PRG_DIR)/..
-INC_DIR  += $(PRG_DIR)/../../..
diff --git a/repos/os/src/drivers/sd_card/spec/imx53/target.mk b/repos/os/src/drivers/sd_card/spec/imx53/target.mk
deleted file mode 100644
index 2bea13df0..000000000
--- a/repos/os/src/drivers/sd_card/spec/imx53/target.mk
+++ /dev/null
@@ -1,8 +0,0 @@
-TARGET    = sd_card_drv
-REQUIRES += imx53
-SRC_CC   += main.cc
-SRC_CC   += adma2.cc
-SRC_CC   += esdhcv2.cc
-LIBS     += base
-INC_DIR  += $(PRG_DIR)
-INC_DIR  += $(PRG_DIR)/../../
diff --git a/repos/os/src/drivers/sd_card/spec/omap4/bench/target.mk b/repos/os/src/drivers/sd_card/spec/omap4/bench/target.mk
deleted file mode 100644
index f257cc4e1..000000000
--- a/repos/os/src/drivers/sd_card/spec/omap4/bench/target.mk
+++ /dev/null
@@ -1,6 +0,0 @@
-TARGET   = sd_card_bench
-REQUIRES = omap4
-SRC_CC   = main.cc
-LIBS     = base server
-INC_DIR += $(REP_DIR)/src/drivers/sd_card/spec/omap4
-INC_DIR += $(REP_DIR)/src/drivers/sd_card
diff --git a/repos/os/src/drivers/sd_card/spec/omap4/target.mk b/repos/os/src/drivers/sd_card/spec/omap4/target.mk
deleted file mode 100644
index f4492aeef..000000000
--- a/repos/os/src/drivers/sd_card/spec/omap4/target.mk
+++ /dev/null
@@ -1,5 +0,0 @@
-TARGET   = sd_card_drv
-REQUIRES = omap4
-SRC_CC   = main.cc
-LIBS     = base
-INC_DIR += $(PRG_DIR) $(REP_DIR)/src/drivers/sd_card
diff --git a/repos/os/src/drivers/sd_card/spec/pl180/target.mk b/repos/os/src/drivers/sd_card/spec/pl180/target.mk
deleted file mode 100644
index 958f87843..000000000
--- a/repos/os/src/drivers/sd_card/spec/pl180/target.mk
+++ /dev/null
@@ -1,6 +0,0 @@
-TARGET   = sd_card_drv
-REQUIRES = pl180
-SRC_CC   = main.cc
-LIBS     = base
-
-INC_DIR += $(PRG_DIR)
diff --git a/repos/os/src/drivers/sd_card/spec/rpi/target.mk b/repos/os/src/drivers/sd_card/spec/rpi/target.mk
deleted file mode 100644
index 9c57f8a2f..000000000
--- a/repos/os/src/drivers/sd_card/spec/rpi/target.mk
+++ /dev/null
@@ -1,5 +0,0 @@
-TARGET   = sd_card_drv
-REQUIRES = rpi
-SRC_CC   = main.cc
-LIBS     = base
-INC_DIR += $(PRG_DIR) $(REP_DIR)/src/drivers/sd_card
diff --git a/repos/os/src/drivers/sd_card/target.mk b/repos/os/src/drivers/sd_card/target.mk
new file mode 100644
index 000000000..5df6b6cbd
--- /dev/null
+++ b/repos/os/src/drivers/sd_card/target.mk
@@ -0,0 +1,3 @@
+TARGET = sd_card_drv
+LIBS   = sd_card_drv
+SRC_CC = empty.cc