diff --git a/README b/README
index 59b1504..d9f62be 100644
--- a/README
+++ b/README
@@ -2,35 +2,29 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-The files in this directory constitute the continuous builder:
+The files in these directories constitute the continuous builder:
 
-app/:     an AppEngine server. The code that runs http://build.golang.org/
+app/:      a.k.a the "dashboard"; the App Engine code that runs http://build.golang.org/
 buildlet/: HTTP server that runs on a VM and is told what to write to disk
-           and what command to run. This is cross-compiled to all architectures
+           and what command to run. This is cross-compiled to different architectures
            and is the first program run when a builder VM comes up. It then
-           is contacted by the coordinator to do a build.
-builder/: gobuilder, a Go continuous build client
+           is contacted by the coordinator to do a build. Not all builders use
+           the buildlet (at least not yet).
+builder/: gobuilder, a Go continuous build client. The original Go builder program.
 coordinator/: daemon that runs on CoreOS on Google Compute Engine and manages
-          builds (using the builder in single-shot mode) in Docker containers.
-env/:     configuration files describing the environment of builders and related binaries.
-          Many builders are still configured ad-hoc.
+          builds using Docker containers and/or VMs as needed.
+env/:     configuration files describing the environment of builders and related
+          binaries. Many builders are still configured ad-hoc, without a hermetic
+          environment.
+retrybuilds/: a Go client program to delete build results from the dashboard (app)
+types/:   a Go package contain common types used by other pieces.
 watcher/: a daemon that watches for new commits to the Go repository and
           its sub-repositories, and notifies the dashboard of those commits.
 
-If you wish to run a Go builder, please email golang-dev@googlegroups.com
+If you wish to run a Go builder, please email golang-dev@googlegroups.com first.
+There is documentation at https://golang.org/wiki/DashboardBuilders but
+depending on the type of builder, we may want to run it ourselves, after you
+prepare an environment description (resulting in a VM image) of it. See the env
+directory.
 
-To run a builder:
-
-* Write the key ~gobuild/.gobuildkey 
-  You need to get it from someone who knows the key.
-  You may also use a filename of the form .gobuildkey-$BUILDER if you
-  wish to run builders for multiple targets.
-
-* Append your username and password googlecode.com credentials from
-    https://code.google.com/hosting/settings
-  to the buildkey file in the format "Username\nPassword\n".
-  (This is for uploading tarballs to the project downloads section,
-   and is an optional step.)
-
-* Build and run gobuilder (see its documentation for command-line options).