diff --git a/bin/jbuild b/bin/jbuild
index 13db3926..025dbff1 100644
--- a/bin/jbuild
+++ b/bin/jbuild
@@ -3,8 +3,6 @@
   (libraries (unix jbuilder jbuilder_cmdliner))
   (preprocess no_preprocessing)))
 
-(provides (jbuilder (file main.exe)))
-
 (install
  ((section bin)
   (files ((main.exe as jbuilder)))))
diff --git a/src/artifacts.ml b/src/artifacts.ml
index 6e7a015c..bfddaa88 100644
--- a/src/artifacts.ml
+++ b/src/artifacts.ml
@@ -44,7 +44,7 @@ let create context stanzas =
 
 let binary t name =
   if String_set.mem name t.local_bins then
-    Ok (Path.relative (Config.local_install_dir ~context:t.context.name) name)
+    Ok (Path.relative (Config.local_install_bin_dir ~context:t.context.name) name)
   else
     match String_map.find name t.provides with
     | Some p -> Ok p
@@ -60,8 +60,8 @@ let binary t name =
 let file_of_lib ?(use_provides=false) t ~lib ~file =
   if String_set.mem lib t.local_libs then
     let lib_install_dir =
-      Path.relative (Config.local_install_dir ~context:t.context.name)
-        (Findlib.root_package_name lib)
+      Config.local_install_lib_dir ~context:t.context.name
+        ~package:(Findlib.root_package_name lib)
     in
     Ok (Path.relative lib_install_dir file)
   else
diff --git a/src/artifacts.mli b/src/artifacts.mli
index 67fc07ca..fa303fec 100644
--- a/src/artifacts.mli
+++ b/src/artifacts.mli
@@ -1,8 +1,3 @@
-(** [Named_artifact] provides a way to reference artifacts in jbuild rules without having
-    to hardcode their exact locations. These named artifacts will be looked up
-    appropriately (in the tree, or for the public release, possibly in the PATH or in
-    findlib). *)
-
 open! Import
 
 type t
diff --git a/src/build.ml b/src/build.ml
index 4542699a..eb9d523a 100644
--- a/src/build.ml
+++ b/src/build.ml
@@ -294,7 +294,19 @@ let symlink ~src ~dst =
   else
     path src >>>
     create_file ~target:dst (fun () ->
-      Unix.symlink (Path.to_string src) (Path.to_string dst))
+      let src =
+        if Path.is_root dst then
+          Path.to_string src
+        else
+          Path.reach ~from:(Path.parent dst) src
+      in
+      let dst = Path.to_string dst in
+      begin
+        match Unix.lstat dst with
+        | exception _ -> ()
+        | _ -> Sys.remove dst
+      end;
+      Unix.symlink src dst)
 
 let touch target =
   create_file ~target (fun _ ->
diff --git a/src/config.ml b/src/config.ml
index 7e01ed50..2697ee1d 100644
--- a/src/config.ml
+++ b/src/config.ml
@@ -1,5 +1,13 @@
 open! Import
 
 let local_install_dir =
-  let dir = Path.(relative root) "install" in
+  let dir = Path.(relative root) "_build/install" in
   fun ~context -> Path.relative dir context
+
+let local_install_bin_dir ~context =
+  Path.relative (local_install_dir ~context) "bin"
+
+let local_install_lib_dir ~context ~package =
+  Path.relative
+    (Path.relative (local_install_dir ~context) "lib")
+    package
diff --git a/src/config.mli b/src/config.mli
index 073ef3d6..c7d7f39a 100644
--- a/src/config.mli
+++ b/src/config.mli
@@ -4,3 +4,6 @@ open! Import
 
 (** Local installation directory *)
 val local_install_dir : context:string -> Path.t
+
+val local_install_bin_dir : context:string -> Path.t
+val local_install_lib_dir : context:string -> package:string -> Path.t
diff --git a/src/jbuild_types.ml b/src/jbuild_types.ml
index d608d82c..d2e88e07 100644
--- a/src/jbuild_types.ml
+++ b/src/jbuild_types.ml
@@ -576,7 +576,7 @@ module Rule = struct
             (Chdir
                (str "${ROOT}",
                 Run (str "${bin:ocamllex}",
-                     [str "-q"; str "-o"; str dst; str src])))
+                     [str "-q"; str "-o"; str "${@}"; str "${<}"])))
       })
 
   let ocamllex_vjs = ocamllex_v1
@@ -592,7 +592,7 @@ module Rule = struct
             (Chdir
                (str "${ROOT}",
                 Run (str "${bin:ocamlyacc}",
-                     [str src])))
+                     [str "${<}"])))
       })
 
   let ocamlyacc_vjs = ocamlyacc_v1
diff --git a/src/main.ml b/src/main.ml
index c512def2..8312f6fb 100644
--- a/src/main.ml
+++ b/src/main.ml
@@ -85,6 +85,9 @@ let report_error ?(map_fname=fun x->x) ppf exn ~backtrace =
                         Description: %s\n\
                         Backtrace:\n\
                         %s" msg bt
+  | Unix.Unix_error (err, func, fname) ->
+    Format.fprintf ppf "@{<error>Error@}: %s: %s: %s\n"
+      func fname (Unix.error_message err)
   | _ ->
     let s = Printexc.to_string exn in
     let bt = Printexc.raw_backtrace_to_string backtrace in
@@ -121,8 +124,9 @@ let bootstrap () =
   let main () =
     let anon s = raise (Arg.Bad (Printf.sprintf "don't know what to do with %s\n" s)) in
     Arg.parse
-      [ "-j"   , Set_int Clflags.concurrency, "JOBS concurrency"
-      ; "--dev", Set Clflags.dev_mode       , " set development mode"
+      [ "-j"           , Set_int Clflags.concurrency, "JOBS concurrency"
+      ; "--dev"        , Set Clflags.dev_mode       , " set development mode"
+      ; "--debug-rules", Set Clflags.debug_rules    , " print out rules"
       ]
       anon "Usage: boot.exe [-j JOBS] [--dev]\nOptions are:";
     Future.Scheduler.go ~log:(create_log ())