diff --git a/common.mk b/common.mk
index abd91b35..3b2b08fe 100644
--- a/common.mk
+++ b/common.mk
@@ -34,6 +34,8 @@ lookup_srcs = $(shell find -L $(1)/ -name target -prune -o -iname "*.$(2)" -prin
 SOURCE_DIRS = $(addprefix $(base_dir)/,generators sims/firesim/sim tools/barstools/iocell)
 SCALA_SOURCES = $(call lookup_srcs,$(SOURCE_DIRS),scala)
 VLOG_SOURCES = $(call lookup_srcs,$(SOURCE_DIRS),sv) $(call lookup_srcs,$(SOURCE_DIRS),v)
+# This assumes no SBT meta-build sources
+SBT_SOURCES = $(call lookup_srcs,$(base_dir),sbt)
 
 #########################################################################################
 # rocket and testchipip classes
diff --git a/variables.mk b/variables.mk
index 3abcc63b..82e32105 100644
--- a/variables.mk
+++ b/variables.mk
@@ -130,7 +130,7 @@ SBT ?= java $(JAVA_ARGS) -jar $(ROCKETCHIP_DIR)/sbt-launch.jar
 BLOOP ?= bloop
 BLOOP_CONFIG_DIR ?= $(base_dir)/.bloop
 
-SCALA_BUILDTOOL_DEPS ?= $(base_dir)/build.sbt
+SCALA_BUILDTOOL_DEPS = $(SBT_SOURCES)
 
 ifdef ENABLE_BLOOP
 override SCALA_BUILDTOOL_DEPS += $(BLOOP_CONFIG_DIR)/TIMESTAMP