diff --git a/Makefile b/Makefile
index 60b39e1ba..27ee6f1a0 100644
--- a/Makefile
+++ b/Makefile
@@ -154,16 +154,31 @@ TIME:=$(shell date +"%Y%m%d%H%M")
 defaulttarget: bin/hledgerdev
 
 ######################################################################
-# BUILDING
+# SETUP
+# work in progress
+# Some rules use a sandbox, some don't, ideally we'll handle both cases.
+# Initial dev setup involves:
+#  initialising a sandbox, probably
+#  cabal update, perhaps
+#  cabal clean in hledger packages, perhaps
+#  cabal install dependencies for hledger packages
+#  cabal install hledger-lib and hledger, perhaps hledger-web
+#  at least start cabal build in hledger packages, to make cabal include files (dist/build/{Paths_PKG.hs,cabal_macros.h}) (not working with a sandbox)
+# When done we should be able to make install, repl-{lib,cli,web}, ghci[-web], check etc.
 
-EXTRAINSTALLARGS=
+sandbox: .cabal-sandbox
+
+.cabal-sandbox:
+	cabal sandbox init
+	cabal sandbox add-source ./hledger-lib ./hledger ./hledger-web
 
 # cabal install the main hledger packages and all their dependencies
+# in the sandbox if any, otherwise in the user's package db
 install:
 	$(CABALINSTALL) $(patsubst %,./%,$(PACKAGES)) $(EXTRAINSTALLARGS) --enable-tests
 
-# cabal install the main hledger packages and all their dependencies, more forcibly
-# (may break installed libs, requiring ghc-pkg-clean)
+# cabal install the main hledger packages and all their dependencies more forcibly
+# (can break installed libs, requiring ghc-pkg-clean)
 install-force:
 	$(CABALINSTALL) $(patsubst %,./%,$(PACKAGES)) $(EXTRAINSTALLARGS) --enable-tests --allow-newer --force-reinstalls
 
@@ -184,6 +199,14 @@ allcabal%:
 # all%:
 # 	for p in $(PACKAGES); do (echo doing $* in $$p; cd $$p; $*); done
 
+Reset:
+	cabal sandbox delete
+
+######################################################################
+# BUILDING
+
+EXTRAINSTALLARGS=
+
 # auto-recompile and run (something, eg --help or unit tests) whenever a module changes
 
 auto: auto---version
@@ -353,12 +376,10 @@ tools/generatejournal: tools/generatejournal.hs
 # TESTING
 
 # developer environment checks
-######################################################################
-# DOCUMENTATION
 
 check:
 	@echo sanity-check developer environment:
-	@($(SHELLTEST) checks -- --threads=8 \
+	@($(SHELLTEST) checks -- \
 		&& echo $@ PASSED) || echo $@ FAILED
 
 
@@ -367,6 +388,10 @@ check:
 packdeps:
 	for p in $(PACKAGES); do packdeps $$p/$$p.cabal; done
 
+######################################################################
+# DOCUMENTATION
+
+
 ######################################################################
 # RELEASING
 
@@ -576,10 +601,10 @@ viewcoverage:
 
 # get a debug prompt
 ghci:
-	$(GHCI) $(WARNINGS) $(INCLUDEPATHS) $(MAIN)
+	cabal exec $(GHCI) -- $(WARNINGS) $(INCLUDEPATHS) $(MAIN)
 
-ghciweb:
-	$(GHCI) $(BUILDFLAGS) $(WEBLANGEXTS) hledger-web/app/main.hs
+ghci-web:
+	cabal exec $(GHCI) -- $(BUILDFLAGS) $(WEBLANGEXTS) hledger-web/app/main.hs
 
 repl-lib:
 	(cd hledger-lib; cabal repl)
diff --git a/checks/10-cabal-installed.test b/checks/11-cabal-installed.test
similarity index 100%
rename from checks/10-cabal-installed.test
rename to checks/11-cabal-installed.test
diff --git a/checks/10-ghc-installed.test b/checks/12-ghc-installed.test
similarity index 100%
rename from checks/10-ghc-installed.test
rename to checks/12-ghc-installed.test
diff --git a/checks/20-ghc-pkg-check.test b/checks/21-ghc-pkg-check.test
similarity index 100%
rename from checks/20-ghc-pkg-check.test
rename to checks/21-ghc-pkg-check.test
diff --git a/checks/31-hledger-lib-cabal-deps-installed.test b/checks/31-hledger-lib-cabal-deps-installed.test
deleted file mode 100644
index f166b1ba6..000000000
--- a/checks/31-hledger-lib-cabal-deps-installed.test
+++ /dev/null
@@ -1,5 +0,0 @@
-# hledger-lib's cabal dependencies are installed
-cabal install ./hledger-lib --only-dep --dry || echo HINT: cabal install ./hledger-lib --only-dep
->>> /All the requested packages are already installed/
->>>2
->>>= 0
diff --git a/checks/32-hledger-cli-cabal-deps-installed.test b/checks/32-hledger-cli-cabal-deps-installed.test
deleted file mode 100644
index 1423c896c..000000000
--- a/checks/32-hledger-cli-cabal-deps-installed.test
+++ /dev/null
@@ -1,5 +0,0 @@
-# hledger's cabal dependencies are installed
-cabal install ./hledger --only-dep --dry || echo HINT: cabal install ./hledger-lib
->>> /All the requested packages are already installed/
->>>2
->>>= 0
diff --git a/checks/33-hledger-web-cabal-deps-installed.test b/checks/33-hledger-web-cabal-deps-installed.test
deleted file mode 100644
index 1e8388cea..000000000
--- a/checks/33-hledger-web-cabal-deps-installed.test
+++ /dev/null
@@ -1,5 +0,0 @@
-# hledger-lib's cabal dependencies are installed
-cabal install ./hledger-web --only-dep --dry || echo HINT: cabal install ./hledger
->>> /All the requested packages are already installed/
->>>2
->>>= 0
diff --git a/checks/51-make-ghci.test b/checks/51-make-ghci.test
index 2a1b0fc8c..b60fb49b6 100644
--- a/checks/51-make-ghci.test
+++ b/checks/51-make-ghci.test
@@ -1,4 +1,4 @@
 # hledger+hledger-lib GHCI prompt works
 echo :q | make ghci | tail
->>> /Ok, modules loaded: Hledger, /
+>>> /Ok, modules loaded/
 >>>= 0
diff --git a/checks/52-make-ghci-web.test b/checks/52-make-ghci-web.test
index 8861bb05e..8fc345300 100644
--- a/checks/52-make-ghci-web.test
+++ b/checks/52-make-ghci-web.test
@@ -1,4 +1,4 @@
 # hledger-web+hledger+hledger-lib GHCI prompt works
-echo :q | make ghciweb | tail
->>> /Ok, modules loaded: Settings, Main, /
+echo :q | make ghci-web | tail
+>>> /Ok, modules loaded/
 >>>= 0