diff -Nru pk4-4/cmd/pk4-edith/edith.css pk4-5/cmd/pk4-edith/edith.css
--- pk4-4/cmd/pk4-edith/edith.css	1970-01-01 00:00:00.000000000 +0000
+++ pk4-5/cmd/pk4-edith/edith.css	2017-10-22 07:07:57.000000000 +0000
@@ -0,0 +1,43 @@
+html, body {
+    width: 100vw;
+    min-height: 100vh;
+    margin: 0;
+    padding: 0;
+}
+
+body {
+    display: grid;
+    grid-template-rows: 2em 80vh auto;
+    /* nav:editor ratio is 3:9 */
+    grid-template-columns: minmax(200px, 3fr) 9fr;
+    grid-template-areas: "nav toolbar"
+			     "nav editor"
+			     "nav pending";
+}
+
+#navigation {
+    grid-area: nav;
+    max-height: 100vh;
+    background-color: #c0c0c0;
+    overflow: scroll;
+}
+
+#editor {
+    grid-area: editor;
+    max-height: 100%;
+    overflow: hidden;
+    background-color: #c0c0ff;
+}
+
+#editor .CodeMirror {
+    height: 100%;
+}
+
+#toolbar {
+    grid-area: toolbar;
+}
+
+#pending {
+    grid-area: pending;
+    background-color: #c0c000;
+}
diff -Nru pk4-4/cmd/pk4-edith/edith.go pk4-5/cmd/pk4-edith/edith.go
--- pk4-4/cmd/pk4-edith/edith.go	1970-01-01 00:00:00.000000000 +0000
+++ pk4-5/cmd/pk4-edith/edith.go	2017-10-22 07:27:10.000000000 +0000
@@ -0,0 +1,115 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"path"
+	"path/filepath"
+	"sort"
+	"strings"
+)
+
+type handlerFunc func(w http.ResponseWriter, r *http.Request) error
+
+func errorTo502(f handlerFunc) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if err := f(w, r); err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+		}
+	})
+}
+
+// shiftPath splits off the first component of p, which will be cleaned of
+// relative components before processing. head will never contain a slash and
+// tail will always be a rooted path without trailing slash.
+func shiftPath(p string) (head, tail string) {
+	p = path.Clean("/" + p)
+	i := strings.Index(p[1:], "/") + 1
+	if i <= 0 {
+		return p[1:], "/"
+	}
+	return p[1:i], p[i:]
+}
+
+func listHandler(w http.ResponseWriter, r *http.Request) error {
+	// TODO: list all packages from /var/cache/pk4/completions.src.txt
+	fmt.Fprintf(w, "ohai!")
+	return nil
+}
+
+// lsrHandler returns a recursive listing of filenames of the specified source
+// package in the specified version.
+//
+// It is typically called by the JavaScript editor when opening a source
+// package.
+func lsrHandler(w http.ResponseWriter, r *http.Request) error {
+	srcpackage, tail := shiftPath(r.URL.Path)
+	srcversion, _ := shiftPath(tail)
+	if srcpackage == "" || srcversion == "" {
+		return fmt.Errorf("syntax: /ls-R/<srcpackage>/<srcversion>")
+	}
+	// TODO: ensure the package is in the cache beforehand
+	var paths []string
+	dir := filepath.Join("/home/michael/.cache/pk4/", srcpackage+"-"+srcversion) + "/"
+	if err := filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if info != nil && info.IsDir() &&
+			(filepath.Base(path) == ".git" ||
+				filepath.Base(path) == ".pc") {
+			return filepath.SkipDir
+		}
+		if rel := strings.TrimPrefix(path, dir); rel != "" {
+			paths = append(paths, rel)
+		}
+		return nil
+	}); err != nil {
+		return err
+	}
+	sort.Strings(paths)
+	if err := json.NewEncoder(w).Encode(paths); err != nil {
+		return err
+	}
+	log.Printf("pkg %q, version %q", srcpackage, srcversion)
+	return nil
+}
+
+// origHandler serves original, unmodified source package files from the pk4
+// cache.
+//
+// TODO: use snapshot.d.n instead?
+func origHandler(w http.ResponseWriter, r *http.Request) error {
+	srcpackage, tail1 := shiftPath(r.URL.Path)
+	srcversion, tail := shiftPath(tail1)
+	if srcpackage == "" || srcversion == "" {
+		return fmt.Errorf("syntax: /orig/<srcpackage>/<srcversion>/<path>")
+	}
+	log.Printf("pkg %q, version %q, path %q", srcpackage, srcversion, tail)
+	dir := filepath.Join("/home/michael/.cache/pk4/", srcpackage+"-"+srcversion) + "/"
+	http.ServeFile(w, r, filepath.Join(dir, tail))
+	return nil
+}
+
+func main() {
+	http.Handle("/", http.FileServer(http.Dir(".")))
+	http.HandleFunc("/edit/", func(w http.ResponseWriter, r *http.Request) {
+		http.ServeFile(w, r, "edith.html")
+	})
+	http.Handle("/list", errorTo502(listHandler))
+	// TODO: middleware to set cache header to \infty
+	http.Handle("/ls-R/", http.StripPrefix("/ls-R/", errorTo502(lsrHandler)))
+	http.Handle("/orig/", http.StripPrefix("/orig/", errorTo502(origHandler)))
+	log.Fatal(http.ListenAndServe(":3391", nil))
+}
+
+/* TODO:
+envisioned contributor workflow:
+1. future contributor creates a guest account (pending state)
+2. current DD vouches for that guest account
+3. guest account can now be used for authN via sso.d.o
+4. authZ is service-specific. e.g., user can create new gitlab repos under their guest-acc space, but not write to any debian ones (yet)
+*/
diff -Nru pk4-4/cmd/pk4-edith/edith.html pk4-5/cmd/pk4-edith/edith.html
--- pk4-4/cmd/pk4-edith/edith.html	1970-01-01 00:00:00.000000000 +0000
+++ pk4-5/cmd/pk4-edith/edith.html	2017-10-22 07:09:58.000000000 +0000
@@ -0,0 +1,27 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>Edith</title>
+    <link rel="stylesheet" href="/edith.css">
+    <script src="https://cdnjs.cloudflare.com/ajax/libs/codemirror/5.31.0/codemirror.js" integrity="sha256-kPB7LHdVFahH8BvmASaVYAOIzK+Rz7F9Yxzh5xg+uCQ=" crossorigin="anonymous"></script>
+    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/codemirror/5.31.0/codemirror.css" integrity="sha256-tM+c7KO0XMWr6VRsrUG1KosdU1VC/PcUwS6Z4ZSWRaM=" crossorigin="anonymous" />
+  </head>
+  <body>
+    <nav id="navigation">
+      navigation pane
+    </nav>
+    <div id="toolbar">
+      <a href="#" id="savebtn">Save</a>
+      <a href="#" id="diffbtn">Diff</a>
+    </div>
+    <div id="editor">
+      <textarea id="editor-ta">
+	editor pane
+      </textarea>
+    </div>
+    <div id="pending">
+      pending changes pane
+    </div>
+    <script src="/edith.js"></script>
+  </body>
+</html>
diff -Nru pk4-4/cmd/pk4-edith/edith.js pk4-5/cmd/pk4-edith/edith.js
--- pk4-4/cmd/pk4-edith/edith.js	1970-01-01 00:00:00.000000000 +0000
+++ pk4-5/cmd/pk4-edith/edith.js	2017-10-22 07:09:40.000000000 +0000
@@ -0,0 +1,119 @@
+// TODO: consider using typescript?
+console.log('ohai!');
+
+// TODO: load list for all packages
+
+var parts = document.location.pathname.split(/\//);
+// TODO: error checking
+var srcpackage = parts[2];
+var srcversion = parts[3];
+var path = parts.slice(4).join("/");
+
+// TODO: error handling
+fetch('/ls-R/' + srcpackage + '/' + srcversion).then(function(response) {
+    return response.json();
+}).then(function(list) {
+    // TODO: expandable file tree browser widget. does codemirror have/recommend sth?
+    var navigationList = document.createElement('ul');
+    for (let fn of list) {
+	var li = document.createElement('li');
+	// TODO: click handler to load file in place without triggering a whole app reload
+	var a = document.createElement('a');
+	a.setAttribute('href', '/edit/' + srcpackage + '/' + srcversion + '/' + fn);
+	a.appendChild(document.createTextNode(fn));
+	li.appendChild(a);
+	navigationList.appendChild(li);
+    }
+    document.getElementById('navigation').appendChild(navigationList);
+});
+
+var ta = document.getElementById('editor-ta');
+
+function loadPending(srcpackage, srcversion) {
+    var pendingKey = JSON.stringify({
+	type: 'pending',
+	srcpackage: srcpackage,
+	srcversion: srcversion,
+    });
+    var pending = window.localStorage.getItem(pendingKey);
+    if (pending === null) {
+	return {};
+    }
+    return JSON.parse(pending);
+}
+
+var pending = loadPending(srcpackage, srcversion);
+
+var pendingList = document.createElement('ul');
+for (fn in pending) {
+    var li = document.createElement('li');
+    var a = document.createElement('a');
+    a.setAttribute('href', '/edit/' + srcpackage + '/' + srcversion + '/' + fn);
+    a.appendChild(document.createTextNode(fn));
+    li.appendChild(a);
+    pendingList.appendChild(li);
+}
+document.getElementById('pending').appendChild(pendingList);
+
+var myCodeMirror;
+function load(srcpackage, srcversion, path, pending) {
+    if (pending[path] === undefined) {
+	// TODO: error handling
+	fetch('/orig/' + srcpackage + '/' + srcversion + '/' + path).then(function(response) {
+	    return response.text();
+	}).then(function(text) {
+	    ta.value = text;
+	    myCodeMirror = CodeMirror.fromTextArea(
+		ta,
+		{
+		    lineNumbers: true,
+		});
+	});
+	return;
+    }
+    var valueKey = JSON.stringify({
+	type: 'file',
+	srcpackage: srcpackage,
+	srcversion: srcversion,
+	path: path,
+    });
+    var value = window.localStorage.getItem(valueKey);
+    if (!value) {
+	// TODO: error message: corrupt localStorage
+	return "corrupt localStorage";
+    }
+    ta.value = value;
+    myCodeMirror = CodeMirror.fromTextArea(
+	ta,
+	{
+	    lineNumbers: true,
+	});
+}
+
+load(srcpackage, srcversion, path, pending);
+
+var saveBtn = document.getElementById('savebtn');
+saveBtn.addEventListener('click', function(ev) {
+    console.log('save!');
+    // TODO: is JSON.stringify guaranteed to be deterministic, or should we use a different key format?
+    var valueKey = JSON.stringify({
+	type: 'file',
+	srcpackage: srcpackage,
+	srcversion: srcversion,
+	path: path,
+    });
+    window.localStorage.setItem(valueKey, myCodeMirror.getValue());
+    var pendingKey = JSON.stringify({
+	type: 'pending',
+	srcpackage: srcpackage,
+	srcversion: srcversion,
+    });
+    var pending = window.localStorage.getItem(pendingKey);
+    if (pending !== null) {
+	pending[path] = true
+    } else {
+	pending = {path: true};
+    }
+    window.localStorage.setItem(pendingKey, JSON.stringify(pending));
+    ev.preventDefault();
+});
diff -Nru pk4-4/debian/changelog pk4-5/debian/changelog
--- pk4-4/debian/changelog	2018-01-05 08:35:29.000000000 +0000
+++ pk4-5/debian/changelog	2018-01-14 19:36:08.000000000 +0000
@@ -1,3 +1,9 @@
+pk4 (5) unstable; urgency=medium
+
+  * “avail” → “make available” (closes: #881343)
+
+ -- Michael Stapelberg <stapelberg@debian.org>  Sun, 14 Jan 2018 20:36:08 +0100
+
 pk4 (4) unstable; urgency=medium
 
   * pk4-replace.1: add another example to illustrate how options are passed
diff -Nru pk4-4/debian/control pk4-5/debian/control
--- pk4-4/debian/control	2018-01-05 08:35:29.000000000 +0000
+++ pk4-5/debian/control	2018-01-14 19:34:40.000000000 +0000
@@ -21,7 +21,7 @@
 	 systemd-sysv
 Recommends: sbuild
 Built-Using: ${misc:Built-Using}
-Description: avail the Debian source package producing the specified package
+Description: make available the Debian source package producing the specified package
  pk4 resolves the specified argument(s) as either:
  .
  1. the name of a Debian binary package, and selects its Debian source package.
diff -Nru pk4-4/pk4.1 pk4-5/pk4.1
--- pk4-4/pk4.1	2018-01-05 08:35:29.000000000 +0000
+++ pk4-5/pk4.1	2018-01-14 19:34:30.000000000 +0000
@@ -11,7 +11,7 @@
 .TH pk4 1 "OCTOBER 2017" Linux "User Manuals"
 
 .SH NAME
-pk4 \- avail the Debian source package producing the specified package
+pk4 \- make available the Debian source package producing the specified package
 
 .SH SYNOPSIS
 .B pk4
diff -Nru pk4-4/pk4-generate-index.1 pk4-5/pk4-generate-index.1
--- pk4-4/pk4-generate-index.1	2018-01-05 08:35:29.000000000 +0000
+++ pk4-5/pk4-generate-index.1	2018-01-14 19:34:36.000000000 +0000
@@ -32,6 +32,6 @@
 .SH SEE ALSO
 .TP
 .IR pk4(1)
-avail the Debian source package producing the specified package
+make available the Debian source package producing the specified package
 .SH AUTHOR
 Michael Stapelberg <stapelberg at debian.org>
diff -Nru pk4-4/pk4-replace.1 pk4-5/pk4-replace.1
--- pk4-4/pk4-replace.1	2018-01-05 08:35:29.000000000 +0000
+++ pk4-5/pk4-replace.1	2018-01-14 19:34:06.000000000 +0000
@@ -73,7 +73,7 @@
 .SH SEE ALSO
 .TP
 .IR pk4(1)
-avail the Debian source package producing the specified package
+make available the Debian source package producing the specified package
 .TP
 .IR sbuild(1)
 build debian packages from source
diff -Nru pk4-4/README.md pk4-5/README.md
--- pk4-4/README.md	2018-01-05 08:35:29.000000000 +0000
+++ pk4-5/README.md	2018-01-14 19:34:18.000000000 +0000
@@ -1,4 +1,4 @@
-# pk4 — avail the Debian source package producing the specified package
+# pk4 — make available the Debian source package producing the specified package
 
 Please see [the pk4(1)
 manpage](https://manpages.debian.org/unstable/pk4/pk4.1.en.html) for
@@ -6,8 +6,8 @@
 
 ## Terminal screencast
 
-Here is a terminal screencast of the tool in action, availing the sources of i3,
-applying a patch, rebuilding the package and replacing the installed binary
-packages:
+Here is a terminal screencast of the tool in action, making available the
+sources of i3, applying a patch, rebuilding the package and replacing the
+installed binary packages:
 
 [![asciicast](https://asciinema.org/a/TgYn2wkABiob14WKb2UefNl9f.png)](https://asciinema.org/a/TgYn2wkABiob14WKb2UefNl9f)