diff --git a/maintner/cmd/maintserve/maintserve.go b/maintner/cmd/maintserve/maintserve.go
index ef4e286..e33d5eb 100644
--- a/maintner/cmd/maintserve/maintserve.go
+++ b/maintner/cmd/maintserve/maintserve.go
@@ -2,13 +2,16 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// maintserve is a program that serves Go issues over HTTP, so they
-// can be viewed in a browser. It uses x/build/maintner/godata as
-// its backing source of data.
+// maintserve is a program that serves Go issues and CLs over HTTP,
+// so they can be viewed in a browser. It uses x/build/maintner/godata
+// as its backing source of data.
 //
 // It statically embeds all the resources it uses, so it's possible to use
 // it when offline. During that time, the corpus will not be able to update,
 // and GitHub user profile pictures won't load.
+//
+// maintserve displays partial Gerrit CL data that is available within the
+// maintner corpus. Code diffs and inline review comments are not included.
 package main
 
 import (
@@ -24,6 +27,8 @@
 	"strings"
 	"time"
 
+	"dmitri.shuralyov.com/app/changes"
+	maintnerchange "dmitri.shuralyov.com/service/change/maintner"
 	"github.com/shurcooL/gofontwoff"
 	"github.com/shurcooL/httpgzip"
 	"github.com/shurcooL/issues"
@@ -53,6 +58,7 @@
 	if err != nil {
 		return err
 	}
+
 	issuesService := maintnerissues.NewService(corpus)
 	issuesApp := issuesapp.New(issuesService, nil, issuesapp.Options{
 		HeadPre: `<meta name="viewport" content="width=device-width">
@@ -71,17 +77,29 @@
 		DisableReactions: true,
 	})
 
-	// TODO: Implement background updates for corpus while the appliation is running.
+	changeService := maintnerchange.NewService(corpus)
+	changesApp := changes.New(changeService, nil, changes.Options{
+		HeadPre: `<meta name="viewport" content="width=device-width">
+<link href="/assets/fonts/fonts.css" rel="stylesheet" type="text/css">
+<link href="/assets/style.css" rel="stylesheet" type="text/css">`,
+		HeadPost: `<style type="text/css">
+	.markdown-body { font-family: Go; }
+	tt, code, pre  { font-family: "Go Mono"; }
+</style>`,
+		BodyPre:          `<div style="max-width: 800px; margin: 0 auto 100px auto;">`,
+		DisableReactions: true,
+	})
+
+	// TODO: Implement background updates for corpus while the application is running.
 	//       Right now, it only updates at startup.
-	//       It's likely just a matter of calling RLock/RUnlock before all read operations,
-	//       and launching a background goroutine that occasionally calls corpus.Update()
-	//       or corpus.Sync() or something.
+	//       See gido source code for an example of how to do this.
 
 	printServingAt(*httpFlag)
 	err = http.ListenAndServe(*httpFlag, &handler{
-		c:             corpus,
-		fontsHandler:  httpgzip.FileServer(gofontwoff.Assets, httpgzip.FileServerOptions{}),
-		issuesHandler: issuesApp,
+		c:              corpus,
+		fontsHandler:   httpgzip.FileServer(gofontwoff.Assets, httpgzip.FileServerOptions{}),
+		issuesHandler:  issuesApp,
+		changesHandler: changesApp,
 	})
 	return err
 }
@@ -97,9 +115,10 @@
 // handler handles all requests to maintserve. It acts like a request multiplexer,
 // choosing from various endpoints and parsing the repository ID from URL.
 type handler struct {
-	c             *maintner.Corpus
-	fontsHandler  http.Handler
-	issuesHandler http.Handler
+	c              *maintner.Corpus
+	fontsHandler   http.Handler
+	issuesHandler  http.Handler
+	changesHandler http.Handler
 }
 
 func (h *handler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
@@ -122,24 +141,42 @@
 		return
 	}
 
-	// Handle "/owner/repo/..." URLs.
 	elems := strings.SplitN(req.URL.Path[1:], "/", 3)
 	if len(elems) < 2 {
 		http.Error(w, "404 Not Found", http.StatusNotFound)
 		return
 	}
-	owner, repo := elems[0], elems[1]
-	baseURLLen := 1 + len(owner) + 1 + len(repo) // Base URL is "/owner/repo".
-	if baseURL := req.URL.Path[:baseURLLen]; req.URL.Path == baseURL+"/" {
-		// Redirect "/owner/repo/" to "/owner/repo".
-		if req.URL.RawQuery != "" {
-			baseURL += "?" + req.URL.RawQuery
+	switch strings.HasSuffix(elems[0], ".googlesource.com") {
+	case false:
+		// Handle "/owner/repo/..." GitHub repository URLs.
+		owner, repo := elems[0], elems[1]
+		baseURLLen := 1 + len(owner) + 1 + len(repo) // Base URL is "/owner/repo".
+		if baseURL := req.URL.Path[:baseURLLen]; req.URL.Path == baseURL+"/" {
+			// Redirect "/owner/repo/" to "/owner/repo".
+			if req.URL.RawQuery != "" {
+				baseURL += "?" + req.URL.RawQuery
+			}
+			http.Redirect(w, req, baseURL, http.StatusFound)
+			return
 		}
-		http.Redirect(w, req, baseURL, http.StatusFound)
-		return
+		req = stripPrefix(req, baseURLLen)
+		h.serveIssues(w, req, maintner.GitHubRepoID{Owner: owner, Repo: repo})
+
+	case true:
+		// Handle "/server/project/..." Gerrit project URLs.
+		server, project := elems[0], elems[1]
+		baseURLLen := 1 + len(server) + 1 + len(project) // Base URL is "/server/project".
+		if baseURL := req.URL.Path[:baseURLLen]; req.URL.Path == baseURL+"/" {
+			// Redirect "/server/project/" to "/server/project".
+			if req.URL.RawQuery != "" {
+				baseURL += "?" + req.URL.RawQuery
+			}
+			http.Redirect(w, req, baseURL, http.StatusFound)
+			return
+		}
+		req = stripPrefix(req, baseURLLen)
+		h.serveChanges(w, req, server, project)
 	}
-	req = stripPrefix(req, baseURLLen)
-	h.serveIssues(w, req, maintner.GitHubRepoID{Owner: owner, Repo: repo})
 }
 
 var indexHTML = template.Must(template.New("").Parse(`<html>
@@ -152,17 +189,27 @@
 	<body>
 		<div style="max-width: 800px; margin: 0 auto 100px auto;">
 			<h2>maintserve</h2>
-			<h3>Repos</h3>
-			<ul>{{range .}}
-				<li><a href="/{{.RepoID}}">{{.RepoID}}</a> ({{.Count}} issues)</li>
-				{{- end}}
-			</ul>
+			<div style="display: inline-block; width: 50%;">
+				<h3>GitHub Repos</h3>
+				<ul>{{range .Repos}}
+					<li><a href="/{{.RepoID}}">{{.RepoID}}</a> ({{.Count}} issues)</li>
+					{{- end}}
+				</ul>
+			</div><div style="display: inline-block; width: 50%; vertical-align: top;">
+				<h3>Gerrit Projects</h3>
+				<ul>{{range .Projects}}
+					<li><a href="/{{.ServProj}}">{{.ServProj}}</a> ({{.Count}} changes)</li>
+					{{- end}}
+				</ul>
+			</div>
 		</div>
 	<body>
 </html>`))
 
-// serveIndex serves the index page, which lists all available repositories.
+// serveIndex serves the index page, which lists all available
+// GitHub repositories and Gerrit projects.
 func (h *handler) serveIndex(w http.ResponseWriter, req *http.Request) {
+	// Enumerate all GitHub repositories.
 	type repo struct {
 		RepoID maintner.GitHubRepoID
 		Count  uint64 // Issues count.
@@ -187,8 +234,36 @@
 		return repos[i].RepoID.String() < repos[j].RepoID.String()
 	})
 
+	// Enumerate all Gerrit projects.
+	type project struct {
+		ServProj string
+		Count    uint64 // Changes count.
+	}
+	var projects []project
+	err = h.c.Gerrit().ForeachProjectUnsorted(func(r *maintner.GerritProject) error {
+		changes, err := countChanges(r)
+		if err != nil {
+			return err
+		}
+		projects = append(projects, project{
+			ServProj: r.ServerSlashProject(),
+			Count:    changes,
+		})
+		return nil
+	})
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	sort.Slice(projects, func(i, j int) bool {
+		return projects[i].ServProj < projects[j].ServProj
+	})
+
 	w.Header().Set("Content-Type", "text/html; charset=utf-8")
-	err = indexHTML.Execute(w, repos)
+	err = indexHTML.Execute(w, map[string]interface{}{
+		"Repos":    repos,
+		"Projects": projects,
+	})
 	if err != nil {
 		log.Println(err)
 	}
@@ -207,10 +282,23 @@
 	return issues, err
 }
 
-// serveIssues serves issues for repository id.
+// countChanges reports the number of changes in a GerritProject p.
+func countChanges(p *maintner.GerritProject) (uint64, error) {
+	var changes uint64
+	err := p.ForeachCLUnsorted(func(cl *maintner.GerritCL) error {
+		if cl.Private {
+			return nil
+		}
+		changes++
+		return nil
+	})
+	return changes, err
+}
+
+// serveIssues serves issues for GitHub repository id.
 func (h *handler) serveIssues(w http.ResponseWriter, req *http.Request, id maintner.GitHubRepoID) {
 	if h.c.GitHub().Repo(id.Owner, id.Repo) == nil {
-		http.Error(w, fmt.Sprintf("404 Not Found\n\nrepository %q not found", id), http.StatusNotFound)
+		http.Error(w, fmt.Sprintf("404 Not Found\n\nGitHub repository %q not found", id), http.StatusNotFound)
 		return
 	}
 
@@ -221,6 +309,20 @@
 	h.issuesHandler.ServeHTTP(w, req)
 }
 
+// serveChanges serves changes for Gerrit project server/project.
+func (h *handler) serveChanges(w http.ResponseWriter, req *http.Request, server, project string) {
+	if h.c.Gerrit().Project(server, project) == nil {
+		http.Error(w, fmt.Sprintf("404 Not Found\n\nGerrit project %s/%s not found", server, project), http.StatusNotFound)
+		return
+	}
+
+	req = req.WithContext(context.WithValue(req.Context(),
+		changes.RepoSpecContextKey, fmt.Sprintf("%s/%s", server, project)))
+	req = req.WithContext(context.WithValue(req.Context(),
+		changes.BaseURIContextKey, fmt.Sprintf("/%s/%s", server, project)))
+	h.changesHandler.ServeHTTP(w, req)
+}
+
 // stripPrefix returns request r with prefix of length prefixLen stripped from r.URL.Path.
 // prefixLen must not be longer than len(r.URL.Path), otherwise stripPrefix panics.
 // If r.URL.Path is empty after the prefix is stripped, the path is changed to "/".