diff --git a/README.md b/README.md
index 0cf0b42..a045e3b 100644
--- a/README.md
+++ b/README.md
@@ -36,4 +36,9 @@ at `localhost:18080`.
 This tool is a rewrite from scratch of a tool I wrote while at Google
 for exploring the dependency graphs used by the Blaze build system.
 The basic design could be easily be generalized to support any kind of
-dependency graph, independent of language or domain.
+dependency graph, independent of language or domain, or turned into a
+secure multi-user web service that operates on graph data uploaded from
+the client program that generates it.
+
+You can probably tell that web UIs are not my expertise.
+PRs that provide cosmetic improvements are most welcome!
diff --git a/code.js b/code.js
index c3eb126..333b4de 100644
--- a/code.js
+++ b/code.js
@@ -5,8 +5,6 @@ var broken = null // array of 2-arrays of int, the node ids of broken edges.
 
 function onLoad() {
     // Grab data from server: package graph, "directory" tree, broken edges.
-    // TODO(adonovan): opt: put JSON data in the /index.html page?
-    // There's no need for a second HTTP request.
     jQuery.ajax({url: "/data", success: onData})
 }
 
@@ -76,10 +74,9 @@ function onData(data) {
 function selectPkg(json) {
     if (json.Package < 0) {
 	// Non-package "directory" node: clear the fields.
-	$('#json').text("")
 	$('#pkgname').text("none")
 	$('#doc').text("")
-	$('#imports').text("")
+	$('#imports').html("")
 	$('#path').text("")
 	return
     }
@@ -87,25 +84,34 @@ function selectPkg(json) {
     // A package node was selected.
     var pkg = packages[json.Package]
 
-    // Show JSON, for debugging.   
-    $('#json').html("<code>" + JSON.stringify(json) + "</code>")
-
     // Show selected package.
     $('#pkgname').text(pkg.PkgPath)
 
-    // Set link to package documentation.
-    $('#doc').html("<a target='_blank' href='https://pkg.go.dev/" + pkg.PkgPath + "'>doc</a>")
-    
-    // TODO(adonovan): display imports as a set of links,
-    // with as ImportPath text and "select dir tree node" as action.
-    $('#imports').text(json.Imports.join(" "))
+    // Set link to Go package documentation.
+    $('#doc').html("<a title='doc' target='_blank' href='https://pkg.go.dev/" + pkg.PkgPath + "'><img src='https://pkg.go.dev/favicon.ico' width='16' height='16'/></a>")
+
+    // Show imports in a drop-down menu.
+    // Selecting an import acts like clicking on that package in the tree.
+    var imports = $('#imports')
+    imports.html("")
+    var option = document.createElement("option")
+    option.textContent = "..."
+    option.value = "-1"
+    imports.append(option)
+    for (var i in json.Imports) {
+	var imp = json.Imports[i]
+	option = document.createElement("option")
+	option.textContent = packages[imp].PkgPath
+	option.value = "" + imp // package index, used by onSelectImport
+	imports.append(option)
+    }
     
     // Show "break edges" buttons.
     var html = ""
     var path = [].concat(json.Path).reverse() // from root to selected package
     for (var i in path) {
 	var p = packages[path[i]]
-	if (i >= 0) {
+	if (i > 0) {
 	    html += "<button type='button' onclick='breakedge(" + path[i-1] + ", " + path[i] + ", false)'>break</button> "
 		+ "<button type='button' onclick='breakedge(" + path[i-1] + ", " + path[i] + ", true)'>break all</button> "
 		+ "⟶ "
@@ -124,3 +130,11 @@ function unbreak(i, j) {
     // Must reload the page since the graph has changed.
     document.location = "/unbreak?from=" + i + "&to=" + j
 }
+
+// onSelectImport is called by the imports dropdown.
+function onSelectImport(sel) {
+    if (sel.value >= 0) {
+	// Simulate a click on a tree node corresponding to the selected import.
+	$('#tree').jstree('select_node', 'node' + sel.value);
+    }
+}
diff --git a/go.mod b/go.mod
index d22436d..57e26d6 100644
--- a/go.mod
+++ b/go.mod
@@ -3,7 +3,6 @@ module github.com/adonovan/spaghetti
 go 1.16
 
 require (
-	github.com/google/renameio v0.1.0 // indirect
-	golang.org/x/tools v0.1.1-0.20210319172145-bda8f5cee399 // indirect
+	golang.org/x/tools v0.1.1-0.20210319172145-bda8f5cee399
 	golang.org/x/tools/gopls v0.6.9 // indirect
 )
diff --git a/go.sum b/go.sum
index 725b9c6..21a462b 100644
--- a/go.sum
+++ b/go.sum
@@ -5,7 +5,6 @@ github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSs
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/google/go-cmp v0.5.4 h1:L8R9j+yAqZuZjsqh/z+F1NCffTKKLShY6zXTItVIZ8M=
 github.com/google/go-cmp v0.5.4/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
-github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
 github.com/google/safehtml v0.0.2/go.mod h1:L4KWwDsUJdECRAEpZoBn3O64bQaywRscowZjJAzjHnU=
 github.com/jba/templatecheck v0.5.0/go.mod h1:/1k7EajoSErFI9GLHAsiIJEaNLt3ALKNw2TV7z2SYv4=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
@@ -26,7 +25,6 @@ github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9dec
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/mod v0.3.0 h1:RM4zey1++hCTbCVQfnWeKs9/IEsaBLA8vTkd0WVtmH4=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.4.1 h1:Kvvh58BN8Y9/lBi7hTekvtMpm07eUZ0ck5pRHpsMWrY=
@@ -40,7 +38,6 @@ golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4 h1:myAQVi0cGEoqQVR5POX+8RR2mrocKqNN1hmeMqhX27k=
 golang.org/x/sys v0.0.0-20210119212857-b64e53b001e4/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c h1:VwygUrnw9jn88c4u8GD3rZQbqrP/tgas88tPUbBxQrk=
 golang.org/x/sys v0.0.0-20210124154548-22da62e12c0c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
@@ -49,7 +46,6 @@ golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/tools v0.0.0-20210101214203-2dba1e4ea05c/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
-golang.org/x/tools v0.1.0 h1:po9/4sTYwZU9lPhi1tOrb4hCv3qrhiQ77LZfGa2OjwY=
 golang.org/x/tools v0.1.0/go.mod h1:xkSsbof2nBLbhDlRMhhhyNLN/zl3eTqcnHD5viDpcZ0=
 golang.org/x/tools v0.1.1-0.20210319172145-bda8f5cee399 h1:O5bm8buX/OaamnfcBrkjn0SPUIU30jFmaS8lP+ikkxs=
 golang.org/x/tools v0.1.1-0.20210319172145-bda8f5cee399/go.mod h1:9bzcO0MWcOuT0tm1iBGzDVPshzfwoVvREIui8C+MHqU=
diff --git a/index.html b/index.html
index b9271e8..e8e18ad 100644
--- a/index.html
+++ b/index.html
@@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html>
 <head>
-  <title>Spaghetti</title>
+  <title>Spaghetti: dependency analysis for Go packages</title>
   <link rel="stylesheet" type="text/css" href="https://cdnjs.cloudflare.com/ajax/libs/jstree/3.2.1/themes/default/style.min.css" />
   <link rel="stylesheet" type="text/css" href="//fonts.googleapis.com/css?family=Lato" />
   <link rel="stylesheet" type="text/css" href="/style.css" />
@@ -10,34 +10,36 @@
   <script src="/code.js"></script>
 </head>
 <body onload='onLoad()'>
-  <h1>Spaghetti</h1>
+  <h1>Spaghetti: dependency analysis for Go packages</h1>
   <p>
     This tool displays the complete dependencies of these initial packages:
   </p>
   <pre id='initial'>...</pre>
   <p>
-    Click on a package in the tree view to display information about
-    it, including a path by which it is reached from one of the
-    initial packages.  Use the <i>break</i> button to remove an
-    edge from the graph, so that you can assess what edges need to be
-    broken to remove an unwanted dependency.
+    Click on a package in the tree view to display information about it,
+    including a path by which it is reached from one of the initial packages.
+
+    Use the <i>break</i> button to remove an edge from the graph, so
+    that you can assess what edges need to be broken to eliminate an
+    unwanted dependency.
   </p>
 
   <h2>Packages</h2>
   <p>
+    <form style='display: inline;'>
     <span class="tooltip">ⓘ<span class="tooltiptext">
 	This tree shows all dependencies of the initial packages,
 	grouped hierarchically by import path and containing
-	module. <br/>
+	module. <br/><br/>
 
 	Each package has a numeric weight, computed using network
 	flow: this is the size of the graph rooted at the node,
-	divided by the node's in-degree. <br/>
+	divided by the node's in-degree. <br/><br/>
 
-	Click a package to show more information aboutit.</span></span>
-    <form style='display: inline;'>
+	Click a package to show more information about it.
+    </span></span>
       <label for='search'>Filter:
-	<input id='search' type='text' name='filter' size='50'/></label>
+	<input id='search' type='text' name='filter' size='70'/></label>
       <button onclick='this.form.search.value=""'>Clear</button>
     </form>
   </p>
@@ -45,26 +47,25 @@ <h2>Packages</h2>
     <div style='height: 20em;' id='tree'>tree</div>
   </div>
 
-  <h2>Selected package: <span id='pkgname'>none</span></h2>
-  <div id='json' style='display: none; overflow: scroll'>...</div> <!-- debugging -->
-  <p>
-    [<span id='doc'>...</span>]<br/>
-  </p>
+  <h2>Selected package: <span id='pkgname'>none</span>&nbsp;&nbsp;&nbsp;<span id='doc'></span></h2>
   <p>
     <span class="tooltip">ⓘ<span class="tooltiptext">This list shows the packages
 	directly imported by the selected package</span></span>   
-    <label for='imports'>Imports:</label>
-    <code id='imports'>...</code>
+    <label for='imports'>Imports: </label>
+    <select id='imports' onchange='onSelectImport(this)'></select>
   </p>
   <p>
-    <span class="tooltip">ⓘ<span class="tooltiptext">This section
-	displays an arbitrary path from one of the initial packages to
-	the selected package. Click the <i>break</i> button so see how
-	your dependencies would change if you were to remove a single
-	edge. Click <i>break all</i> to remove all inbound edges to a
+    <span class="tooltip">ⓘ<span class="tooltiptext">
+	This section displays an arbitrary path from one of the
+	initial packages to the selected package. Click
+	the <i>break</i> button so see how your dependencies would
+	change if you were to remove a single edge.<br/><br/>
+
+	Click <i>break all</i> to remove all inbound edges to a
 	package, removing it from the graph. This may be useful for
 	removing distracting packages that you don't plan to
-	eliminate.
+	eliminate.<br/><br/>
+	
 	The bold nodes are <i>dominators</i>: nodes that are found on
 	every path to the selected node. One way to break a dependency
 	on a package is to break all dependencies on any of its dominators.
diff --git a/spaghetti.go b/spaghetti.go
index 26dd9f9..4785358 100644
--- a/spaghetti.go
+++ b/spaghetti.go
@@ -101,7 +101,7 @@ func main() {
 	http.Handle("/", http.FileServer(http.FS(content)))
 
 	const addr = "localhost:18080"
-	log.Printf("Listening on %s...", addr)
+	log.Printf("listening on http://%s", addr)
 	if err := http.ListenAndServe(addr, nil); err != nil {
 		log.Fatal(err)
 	}
@@ -256,7 +256,7 @@ func onData(w http.ResponseWriter, req *http.Request) {
 		// Any additional fields will be accessible
 		// in the jstree node's .original field.
 		Package    int // -1 for non-package nodes
-		Imports    []string
+		Imports    []int
 		Dominators []int // path through dom tree, from package to root inclusive
 		Path       []int // path through package graph, from package to root inclusive
 	}
@@ -306,9 +306,9 @@ func onData(w http.ResponseWriter, req *http.Request) {
 				// item.State = { 'opened' : true, 'selected' : true }
 
 				item.Package = e.node.index
-				item.Imports = []string{} // avoid JSON null
+				item.Imports = []int{} // avoid JSON null
 				for _, imp := range e.node.imports {
-					item.Imports = append(item.Imports, imp.Package.ID)
+					item.Imports = append(item.Imports, imp.index)
 				}
 				for n := e.node; n != nil; n = n.Idom() {
 					item.Dominators = append(item.Dominators, n.index)
diff --git a/style.css b/style.css
index 4cfc81d..7f26294 100644
--- a/style.css
+++ b/style.css
@@ -1,9 +1,9 @@
-body { margin: 1em; font-family: "Minion Pro", serif; }
+body { margin: 1em; font-family: "Minion Pro", serif; max-width: 1024px; }
 h1, h2, h3, h4, .jstree-default { font-family: Lato; } 
 code, pre { font-family: Consolas, monospace; }
 code.dom { font-weight: bold; }
-button { font-size: 50%; }
-pre#imports { font-size: 50%; max-height: 3em; overflow: scroll; }
+button { font-size: 90%; }
+pre#initial { margin-left: 1em; }
 
 /* the ⓘ symbol */
 .tooltip {