Makefile: Generate a feed per category

6 files changed, 202 insertions, 76 deletions

diff --git a/.gitignore b/.gitignore
index 6ab3636..99f41e7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,15 +9,19 @@
 *.indexentry
 *.feedentry
 *.sortdata
+*.categorydata
 sortdata.txt
+categories.txt
+categories.xml
 index.htmlheader
 index.htmlfooter
 index.htmllisting
 feed.xml
+feed.*.xml
 *.gz
 /src/sources.txt
 /src/all-contents.txt
-/src/all-snippets-list.txt
+/src/all-filelists.txt
 /src/install.txt
 /src/sort-expected.txt
 /src/sort-given.txt
diff --git a/Makefile b/Makefile
index e7318c2..bf4f4d5 100644
--- a/Makefile
+++ b/Makefile
@@ -24,42 +24,45 @@ PUBURL       = public.asc
 
 
 .SUFFIXES:
-.SUFFIXES: .adoc .conf .snippets .indexentry .feedentry .sortdata .xml
+.SUFFIXES: .adoc .conf .snippets .indexentry .feedentry .sortdata .xml .txt
 .SUFFIXES: .htmlbody .htmlheader .htmlfooter .htmllisting .html .links .caslinks
-.SUFFIXES: .gz
+.SUFFIXES: .categorydata .gz
 
 .adoc.conf:
 	mkwb conf src/global.conf $< > $@
 
 .adoc.htmlbody:
-	mkwb htmlbody   $< > $@
+	mkwb htmlbody     $< > $@
 
 .htmlbody.html:
-	mkwb html       $< > $@
+	mkwb html         $< > $@
 
 .conf.htmlheader:
-	mkwb html -H    $< > $@
+	mkwb html -H      $< > $@
 
 .conf.htmlfooter:
-	mkwb html -F    $< > $@
+	mkwb html -F      $< > $@
 
 .conf.htmllisting:
-	mkwb indexbody  $< > $@
+	mkwb indexbody    $< > $@
 
 .adoc.snippets:
-	mkwb snippets   $< > $@
+	mkwb snippets     $< > $@
 
 .conf.indexentry:
-	mkwb indexentry $< > $@
+	mkwb indexentry   $< > $@
 
 .htmlbody.feedentry:
-	mkwb feedentry  $< > $@
+	mkwb feedentry    $< > $@
 
 .conf.sortdata:
-	mkwb sortdata   $< > $@
+	mkwb sortdata     $< > $@
+
+.conf.categorydata:
+	mkwb categorydata $< > $@
 
 .adoc.links:
-	mkwb links      $< > $@
+	mkwb links        $< > $@
 
 .links.caslinks:
 	grep -v '^link:' $< | xargs -I_ sh -c '\
@@ -72,21 +75,24 @@ all:
 include deps.mk
 
 
-sources.adoc         = $(articles.adoc) $(listings.adoc) $(pages.adoc)
-sources.htmlbody     = $(sources.adoc:.adoc=.htmlbody)
-sources.html         = $(sources.adoc:.adoc=.html)
-sources.snippets     = $(sources.adoc:.adoc=.snippets)
-sources.snippets.gz  = $(sources.adoc:.adoc=.snippets.gz)
-sources.conf         = $(sources.adoc:.adoc=.conf)
-sources.links        = $(sources.adoc:.adoc=.links)
-sources.caslinks     = $(sources.adoc:.adoc=.caslinks)
-articles.indexentry  = $(articles.adoc:.adoc=.indexentry)
-articles.feedentry   = $(articles.adoc:.adoc=.feedentry)
-articles.sortdata    = $(articles.adoc:.adoc=.sortdata)
-listings.htmlheader  = $(listings.adoc:.adoc=.htmlheader)
-listings.htmlfooter  = $(listings.adoc:.adoc=.htmlfooter)
-listings.htmllisting = $(listings.adoc:.adoc=.htmllisting)
-listings.html        = $(listings.adoc:.adoc=.html)
+sources.adoc          = $(articles.adoc) $(listings.adoc) $(pages.adoc)
+sources.htmlbody      = $(sources.adoc:.adoc=.htmlbody)
+sources.html          = $(sources.adoc:.adoc=.html)
+sources.snippets      = $(sources.adoc:.adoc=.snippets)
+sources.snippets.gz   = $(sources.adoc:.adoc=.snippets.gz)
+sources.conf          = $(sources.adoc:.adoc=.conf)
+sources.links         = $(sources.adoc:.adoc=.links)
+sources.caslinks      = $(sources.adoc:.adoc=.caslinks)
+articles.indexentry   = $(articles.adoc:.adoc=.indexentry)
+articles.feedentry    = $(articles.adoc:.adoc=.feedentry)
+articles.sortdata     = $(articles.adoc:.adoc=.sortdata)
+articles.categorydata = $(articles.adoc:.adoc=.categorydata)
+listings.htmlheader   = $(listings.adoc:.adoc=.htmlheader)
+listings.htmlfooter   = $(listings.adoc:.adoc=.htmlfooter)
+listings.htmllisting  = $(listings.adoc:.adoc=.htmllisting)
+listings.html         = $(listings.adoc:.adoc=.html)
+categories.xml        = $(categories.txt:.txt=.xml)
+categories.xml.gz     = $(categories.txt:.txt=.xml.gz)
 
 sources = \
 	$(sources.adoc)                          \
@@ -127,9 +133,11 @@ contents = \
 	src/content/security.txt                 \
 	src/content/security.txt.gz              \
 
-all-snippets = \
+all-filelists = \
 	$(sources.snippets)                      \
 	$(sources.snippets.gz)                   \
+	$(categories.xml)                        \
+	$(categories.xml.gz)                     \
 
 all-contents = \
 	$(contents)                              \
@@ -154,6 +162,10 @@ derived-assets = \
 	$(articles.indexentry)                   \
 	$(articles.feedentry)                    \
 	$(articles.sortdata)                     \
+	$(articles.categorydata)                 \
+	$(categories.txt)                        \
+	$(categories.xml)                        \
+	$(categories.xml.gz)                     \
 	email.txt                                \
 	baseurl.txt                              \
 	fingerprint.txt                          \
@@ -162,7 +174,7 @@ derived-assets = \
 	src/content/security.txt.gz              \
 	src/content/.well-known/security.txt     \
 	src/all-contents.txt                     \
-	src/all-snippets-list.txt                \
+	src/all-filelists.txt                    \
 	src/install.txt                          \
 	src/sort-expected.txt                    \
 	src/sort-given.txt                       \
@@ -175,6 +187,8 @@ side-assets = \
 	src/collections/*/*/*/*/*.html.*.txt.gz  \
 	src/collections/*/index.html.*.txt       \
 	src/collections/*/sortdata.txt           \
+	src/collections/*/feed.*.xml             \
+	src/collections/*/feed.*.xml.gz          \
 	src/collections/*/*.sortdata             \
 	src/pages/*/*.html.*.txt                 \
 	src/content/.well-known/                 \
@@ -207,6 +221,16 @@ src/global.conf: src/base.conf
 $(listings.html):
 	cat $*.htmlheader $*.htmllisting $*.htmlbody $*.htmlfooter > $@
 
+$(categories.txt):
+	mkwb categories $(@D) > $@
+
+$(categories.xml):
+	for f in `cat $*.txt`; do \
+		c="`printf '%s\n' "$$f" | cut -d. -f2`"; \
+		mkwb feed src/global.conf "$$f" > $(@D)/feed."$$c".xml; \
+		printf '%s\n' $(@D)/feed."$$c".xml; \
+	done > $@
+
 $(feeds.xml):
 	mkwb feed src/global.conf $(@D)/sortdata.txt > $@
 
@@ -214,7 +238,7 @@ $(contents.gz):
 	gzip -9fk $*
 	touch     $@
 
-$(sources.snippets.gz):
+$(sources.snippets.gz) $(categories.xml.gz):
 	if [ -s $* ]; then gzip -9fk `cat $*`; fi
 	sed 's/$$/.gz/' $* > $@
 
@@ -262,11 +286,11 @@ src/sources.txt:
 src/all-contents.txt:
 	printf '%s\n' $(all-contents) > $@
 
-src/all-snippets-list.txt:
-	printf '%s\n' $(all-snippets) > $@
+src/all-filelists.txt:
+	printf '%s\n' $(all-filelists) > $@
 
-src/install.txt: src/all-contents.txt src/all-snippets-list.txt $(all-snippets)
-	cat src/all-contents.txt `cat src/all-snippets-list.txt` > $@
+src/install.txt: src/all-contents.txt src/all-filelists.txt $(all-filelists)
+	cat src/all-contents.txt `cat src/all-filelists.txt` > $@
 
 sources.txt: src/sources.txt
 install.txt: src/install.txt
diff --git a/deps.mk b/deps.mk
index dee7b30..c20c982 100644
--- a/deps.mk
+++ b/deps.mk
@@ -75,6 +75,13 @@ listings.adoc = \
 	src/content/screencasts/index.adoc \
 	src/content/tils/index.adoc \
 
+categories.txt = \
+	src/content/blog/categories.txt \
+	src/content/pastebins/categories.txt \
+	src/content/podcasts/categories.txt \
+	src/content/screencasts/categories.txt \
+	src/content/tils/categories.txt \
+
 feeds.xml = \
 	src/content/blog/feed.xml \
 	src/content/pastebins/feed.xml \
@@ -390,6 +397,11 @@ src/content/pastebins/index.snippets.gz:	src/content/pastebins/index.snippets
 src/content/podcasts/index.snippets.gz:	src/content/podcasts/index.snippets
 src/content/screencasts/index.snippets.gz:	src/content/screencasts/index.snippets
 src/content/tils/index.snippets.gz:	src/content/tils/index.snippets
+src/content/blog/categories.xml.gz:	src/content/blog/categories.xml
+src/content/pastebins/categories.xml.gz:	src/content/pastebins/categories.xml
+src/content/podcasts/categories.xml.gz:	src/content/podcasts/categories.xml
+src/content/screencasts/categories.xml.gz:	src/content/screencasts/categories.xml
+src/content/tils/categories.xml.gz:	src/content/tils/categories.xml
 src/content/blog/feed.xml.gz:	src/content/blog/feed.xml
 src/content/pastebins/feed.xml.gz:	src/content/pastebins/feed.xml
 src/content/podcasts/feed.xml.gz:	src/content/podcasts/feed.xml
@@ -738,6 +750,70 @@ src/content/tils/2021/04/24/clojure-autocurry.sortdata:	src/content/tils/2021/04
 src/content/tils/2021/04/24/scm-nif.sortdata:	src/content/tils/2021/04/24/scm-nif.conf
 src/content/tils/2021/07/23/git-tls-gpg.sortdata:	src/content/tils/2021/07/23/git-tls-gpg.conf
 src/content/tils/2021/08/11/js-bigint-reviver.sortdata:	src/content/tils/2021/08/11/js-bigint-reviver.conf
+src/content/blog/2018/07/17/guix-nixos.categorydata:	src/content/blog/2018/07/17/guix-nixos.conf
+src/content/blog/2018/08/01/npm-ci-reproducibility.categorydata:	src/content/blog/2018/08/01/npm-ci-reproducibility.conf
+src/content/blog/2018/12/21/ytdl-subs.categorydata:	src/content/blog/2018/12/21/ytdl-subs.conf
+src/content/blog/2019/06/02/nixos-stateless-workstation.categorydata:	src/content/blog/2019/06/02/nixos-stateless-workstation.conf
+src/content/blog/2020/08/10/guix-srht.categorydata:	src/content/blog/2020/08/10/guix-srht.conf
+src/content/blog/2020/08/31/database-i-wish-i-had.categorydata:	src/content/blog/2020/08/31/database-i-wish-i-had.conf
+src/content/blog/2020/10/05/cargo2nix.categorydata:	src/content/blog/2020/10/05/cargo2nix.conf
+src/content/blog/2020/10/05/swift2nix.categorydata:	src/content/blog/2020/10/05/swift2nix.conf
+src/content/blog/2020/10/19/feature-flags.categorydata:	src/content/blog/2020/10/19/feature-flags.conf
+src/content/blog/2020/10/20/wrong-interviewing.categorydata:	src/content/blog/2020/10/20/wrong-interviewing.conf
+src/content/blog/2020/11/07/diy-bugs.categorydata:	src/content/blog/2020/11/07/diy-bugs.conf
+src/content/blog/2020/11/08/paradigm-shift-review.categorydata:	src/content/blog/2020/11/08/paradigm-shift-review.conf
+src/content/blog/2020/11/12/database-parsers-trees.categorydata:	src/content/blog/2020/11/12/database-parsers-trees.conf
+src/content/blog/2020/11/14/local-first-review.categorydata:	src/content/blog/2020/11/14/local-first-review.conf
+src/content/blog/2021/01/26/remembering-ann.categorydata:	src/content/blog/2021/01/26/remembering-ann.conf
+src/content/blog/2021/02/17/fallible.categorydata:	src/content/blog/2021/02/17/fallible.conf
+src/content/blog/2021/04/29/relational-review.categorydata:	src/content/blog/2021/04/29/relational-review.conf
+src/content/pastebins/2016/04/05/rpn.categorydata:	src/content/pastebins/2016/04/05/rpn.conf
+src/content/pastebins/2018/07/11/nix-pinning.categorydata:	src/content/pastebins/2018/07/11/nix-pinning.conf
+src/content/pastebins/2018/07/13/guix-nixos-systemd.categorydata:	src/content/pastebins/2018/07/13/guix-nixos-systemd.conf
+src/content/pastebins/2018/07/13/guixbuilder-nixos.categorydata:	src/content/pastebins/2018/07/13/guixbuilder-nixos.conf
+src/content/pastebins/2018/07/13/guixbuilder.categorydata:	src/content/pastebins/2018/07/13/guixbuilder.conf
+src/content/pastebins/2018/07/13/nix-strpad.categorydata:	src/content/pastebins/2018/07/13/nix-strpad.conf
+src/content/pastebins/2018/07/25/nix-exps.categorydata:	src/content/pastebins/2018/07/25/nix-exps.conf
+src/content/pastebins/2018/07/25/nix-showdrv.categorydata:	src/content/pastebins/2018/07/25/nix-showdrv.conf
+src/content/pastebins/2019/06/08/inconsistent-hash.categorydata:	src/content/pastebins/2019/06/08/inconsistent-hash.conf
+src/content/pastebins/2019/12/29/raku-tuple-type.categorydata:	src/content/pastebins/2019/12/29/raku-tuple-type.conf
+src/content/pastebins/2020/01/04/guix-import-failure.categorydata:	src/content/pastebins/2020/01/04/guix-import-failure.conf
+src/content/pastebins/2020/02/14/guix-shebang.categorydata:	src/content/pastebins/2020/02/14/guix-shebang.conf
+src/content/pastebins/2020/11/27/guix-build-local.categorydata:	src/content/pastebins/2020/11/27/guix-build-local.conf
+src/content/pastebins/2020/12/15/guix-pack-fail.categorydata:	src/content/pastebins/2020/12/15/guix-pack-fail.conf
+src/content/pastebins/2021/04/03/naive-slugify-js.categorydata:	src/content/pastebins/2021/04/03/naive-slugify-js.conf
+src/content/pastebins/2021/06/08/reading-session-pt1.categorydata:	src/content/pastebins/2021/06/08/reading-session-pt1.conf
+src/content/pastebins/2021/06/22/curl-wget.categorydata:	src/content/pastebins/2021/06/22/curl-wget.conf
+src/content/pastebins/2021/08/11/h1-spacing.categorydata:	src/content/pastebins/2021/08/11/h1-spacing.conf
+src/content/pastebins/2021/09/02/sicp-3-19.categorydata:	src/content/pastebins/2021/09/02/sicp-3-19.conf
+src/content/pastebins/2021/09/03/sicp-persistent-queue.categorydata:	src/content/pastebins/2021/09/03/sicp-persistent-queue.conf
+src/content/pastebins/2022/07/14/git-cleanup.categorydata:	src/content/pastebins/2022/07/14/git-cleanup.conf
+src/content/pastebins/2023/07/22/funcallable-amop.categorydata:	src/content/pastebins/2023/07/22/funcallable-amop.conf
+src/content/podcasts/2020/12/19/test-entry.categorydata:	src/content/podcasts/2020/12/19/test-entry.conf
+src/content/screencasts/2021/02/07/autoqemu.categorydata:	src/content/screencasts/2021/02/07/autoqemu.conf
+src/content/tils/2020/08/12/filename-timestamp.categorydata:	src/content/tils/2020/08/12/filename-timestamp.conf
+src/content/tils/2020/08/13/code-jekyll.categorydata:	src/content/tils/2020/08/13/code-jekyll.conf
+src/content/tils/2020/08/14/browse-git.categorydata:	src/content/tils/2020/08/14/browse-git.conf
+src/content/tils/2020/08/16/git-search.categorydata:	src/content/tils/2020/08/16/git-search.conf
+src/content/tils/2020/08/28/grep-online.categorydata:	src/content/tils/2020/08/28/grep-online.conf
+src/content/tils/2020/09/04/cli-email-fun-profit.categorydata:	src/content/tils/2020/09/04/cli-email-fun-profit.conf
+src/content/tils/2020/09/05/oldschool-pr.categorydata:	src/content/tils/2020/09/05/oldschool-pr.conf
+src/content/tils/2020/10/11/search-git-history.categorydata:	src/content/tils/2020/10/11/search-git-history.conf
+src/content/tils/2020/11/08/find-broken-symlink.categorydata:	src/content/tils/2020/11/08/find-broken-symlink.conf
+src/content/tils/2020/11/12/diy-nix-bash-ci.categorydata:	src/content/tils/2020/11/12/diy-nix-bash-ci.conf
+src/content/tils/2020/11/12/git-bisect-automation.categorydata:	src/content/tils/2020/11/12/git-bisect-automation.conf
+src/content/tils/2020/11/12/useful-bashvars.categorydata:	src/content/tils/2020/11/12/useful-bashvars.conf
+src/content/tils/2020/11/14/gpodder-media.categorydata:	src/content/tils/2020/11/14/gpodder-media.conf
+src/content/tils/2020/11/30/git-notes-ci.categorydata:	src/content/tils/2020/11/30/git-notes-ci.conf
+src/content/tils/2020/12/15/shellcheck-repo.categorydata:	src/content/tils/2020/12/15/shellcheck-repo.conf
+src/content/tils/2020/12/29/svg.categorydata:	src/content/tils/2020/12/29/svg.conf
+src/content/tils/2021/01/12/curl-awk-emails.categorydata:	src/content/tils/2021/01/12/curl-awk-emails.conf
+src/content/tils/2021/01/17/posix-shebang.categorydata:	src/content/tils/2021/01/17/posix-shebang.conf
+src/content/tils/2021/04/24/cl-generic-precedence.categorydata:	src/content/tils/2021/04/24/cl-generic-precedence.conf
+src/content/tils/2021/04/24/clojure-autocurry.categorydata:	src/content/tils/2021/04/24/clojure-autocurry.conf
+src/content/tils/2021/04/24/scm-nif.categorydata:	src/content/tils/2021/04/24/scm-nif.conf
+src/content/tils/2021/07/23/git-tls-gpg.categorydata:	src/content/tils/2021/07/23/git-tls-gpg.conf
+src/content/tils/2021/08/11/js-bigint-reviver.categorydata:	src/content/tils/2021/08/11/js-bigint-reviver.conf
 
 src/content/blog/index.htmlheader	src/content/blog/index.htmlfooter:	src/content/blog/index.conf
 src/content/pastebins/index.htmlheader	src/content/pastebins/index.htmlfooter:	src/content/pastebins/index.conf
@@ -775,15 +851,18 @@ articles.blog.adoc = \
 	src/content/blog/2021/02/17/fallible.adoc \
 	src/content/blog/2021/04/29/relational-review.adoc \
 
-articles.blog.sortdata   = $(articles.blog.adoc:.adoc=.sortdata)
-articles.blog.indexentry = $(articles.blog.adoc:.adoc=.indexentry)
-articles.blog.feedentry  = $(articles.blog.adoc:.adoc=.feedentry)
+articles.blog.sortdata     = $(articles.blog.adoc:.adoc=.sortdata)
+articles.blog.indexentry   = $(articles.blog.adoc:.adoc=.indexentry)
+articles.blog.feedentry    = $(articles.blog.adoc:.adoc=.feedentry)
+articles.blog.categorydata = $(articles.blog.adoc:.adoc=.categorydata)
 src/content/blog/sortdata.txt:	deps.mk
 	printf '%s\n' $(articles.blog.sortdata) > $@
 
-src/content/blog/feed.xml	src/content/blog/index.htmllisting:	src/content/blog/sortdata.txt	$(articles.blog.sortdata)
+src/content/blog/categories.txt	src/content/blog/feed.xml	src/content/blog/index.htmllisting:	src/content/blog/sortdata.txt	$(articles.blog.sortdata)
 src/content/blog/index.htmllisting:	$(articles.blog.indexentry)
-src/content/blog/feed.xml:	$(articles.blog.feedentry)
+src/content/blog/categories.txt:	$(articles.blog.categorydata)
+src/content/blog/categories.xml:	src/content/blog/categories.txt
+src/content/blog/categories.txt	src/content/blog/feed.xml:	$(articles.blog.feedentry)
 
 
 articles.pastebins.adoc = \
@@ -810,43 +889,52 @@ articles.pastebins.adoc = \
 	src/content/pastebins/2022/07/14/git-cleanup.adoc \
 	src/content/pastebins/2023/07/22/funcallable-amop.adoc \
 
-articles.pastebins.sortdata   = $(articles.pastebins.adoc:.adoc=.sortdata)
-articles.pastebins.indexentry = $(articles.pastebins.adoc:.adoc=.indexentry)
-articles.pastebins.feedentry  = $(articles.pastebins.adoc:.adoc=.feedentry)
+articles.pastebins.sortdata     = $(articles.pastebins.adoc:.adoc=.sortdata)
+articles.pastebins.indexentry   = $(articles.pastebins.adoc:.adoc=.indexentry)
+articles.pastebins.feedentry    = $(articles.pastebins.adoc:.adoc=.feedentry)
+articles.pastebins.categorydata = $(articles.pastebins.adoc:.adoc=.categorydata)
 src/content/pastebins/sortdata.txt:	deps.mk
 	printf '%s\n' $(articles.pastebins.sortdata) > $@
 
-src/content/pastebins/feed.xml	src/content/pastebins/index.htmllisting:	src/content/pastebins/sortdata.txt	$(articles.pastebins.sortdata)
+src/content/pastebins/categories.txt	src/content/pastebins/feed.xml	src/content/pastebins/index.htmllisting:	src/content/pastebins/sortdata.txt	$(articles.pastebins.sortdata)
 src/content/pastebins/index.htmllisting:	$(articles.pastebins.indexentry)
-src/content/pastebins/feed.xml:	$(articles.pastebins.feedentry)
+src/content/pastebins/categories.txt:	$(articles.pastebins.categorydata)
+src/content/pastebins/categories.xml:	src/content/pastebins/categories.txt
+src/content/pastebins/categories.txt	src/content/pastebins/feed.xml:	$(articles.pastebins.feedentry)
 
 
 articles.podcasts.adoc = \
 	src/content/podcasts/2020/12/19/test-entry.adoc \
 
-articles.podcasts.sortdata   = $(articles.podcasts.adoc:.adoc=.sortdata)
-articles.podcasts.indexentry = $(articles.podcasts.adoc:.adoc=.indexentry)
-articles.podcasts.feedentry  = $(articles.podcasts.adoc:.adoc=.feedentry)
+articles.podcasts.sortdata     = $(articles.podcasts.adoc:.adoc=.sortdata)
+articles.podcasts.indexentry   = $(articles.podcasts.adoc:.adoc=.indexentry)
+articles.podcasts.feedentry    = $(articles.podcasts.adoc:.adoc=.feedentry)
+articles.podcasts.categorydata = $(articles.podcasts.adoc:.adoc=.categorydata)
 src/content/podcasts/sortdata.txt:	deps.mk
 	printf '%s\n' $(articles.podcasts.sortdata) > $@
 
-src/content/podcasts/feed.xml	src/content/podcasts/index.htmllisting:	src/content/podcasts/sortdata.txt	$(articles.podcasts.sortdata)
+src/content/podcasts/categories.txt	src/content/podcasts/feed.xml	src/content/podcasts/index.htmllisting:	src/content/podcasts/sortdata.txt	$(articles.podcasts.sortdata)
 src/content/podcasts/index.htmllisting:	$(articles.podcasts.indexentry)
-src/content/podcasts/feed.xml:	$(articles.podcasts.feedentry)
+src/content/podcasts/categories.txt:	$(articles.podcasts.categorydata)
+src/content/podcasts/categories.xml:	src/content/podcasts/categories.txt
+src/content/podcasts/categories.txt	src/content/podcasts/feed.xml:	$(articles.podcasts.feedentry)
 
 
 articles.screencasts.adoc = \
 	src/content/screencasts/2021/02/07/autoqemu.adoc \
 
-articles.screencasts.sortdata   = $(articles.screencasts.adoc:.adoc=.sortdata)
-articles.screencasts.indexentry = $(articles.screencasts.adoc:.adoc=.indexentry)
-articles.screencasts.feedentry  = $(articles.screencasts.adoc:.adoc=.feedentry)
+articles.screencasts.sortdata     = $(articles.screencasts.adoc:.adoc=.sortdata)
+articles.screencasts.indexentry   = $(articles.screencasts.adoc:.adoc=.indexentry)
+articles.screencasts.feedentry    = $(articles.screencasts.adoc:.adoc=.feedentry)
+articles.screencasts.categorydata = $(articles.screencasts.adoc:.adoc=.categorydata)
 src/content/screencasts/sortdata.txt:	deps.mk
 	printf '%s\n' $(articles.screencasts.sortdata) > $@
 
-src/content/screencasts/feed.xml	src/content/screencasts/index.htmllisting:	src/content/screencasts/sortdata.txt	$(articles.screencasts.sortdata)
+src/content/screencasts/categories.txt	src/content/screencasts/feed.xml	src/content/screencasts/index.htmllisting:	src/content/screencasts/sortdata.txt	$(articles.screencasts.sortdata)
 src/content/screencasts/index.htmllisting:	$(articles.screencasts.indexentry)
-src/content/screencasts/feed.xml:	$(articles.screencasts.feedentry)
+src/content/screencasts/categories.txt:	$(articles.screencasts.categorydata)
+src/content/screencasts/categories.xml:	src/content/screencasts/categories.txt
+src/content/screencasts/categories.txt	src/content/screencasts/feed.xml:	$(articles.screencasts.feedentry)
 
 
 articles.tils.adoc = \
@@ -874,12 +962,15 @@ articles.tils.adoc = \
 	src/content/tils/2021/07/23/git-tls-gpg.adoc \
 	src/content/tils/2021/08/11/js-bigint-reviver.adoc \
 
-articles.tils.sortdata   = $(articles.tils.adoc:.adoc=.sortdata)
-articles.tils.indexentry = $(articles.tils.adoc:.adoc=.indexentry)
-articles.tils.feedentry  = $(articles.tils.adoc:.adoc=.feedentry)
+articles.tils.sortdata     = $(articles.tils.adoc:.adoc=.sortdata)
+articles.tils.indexentry   = $(articles.tils.adoc:.adoc=.indexentry)
+articles.tils.feedentry    = $(articles.tils.adoc:.adoc=.feedentry)
+articles.tils.categorydata = $(articles.tils.adoc:.adoc=.categorydata)
 src/content/tils/sortdata.txt:	deps.mk
 	printf '%s\n' $(articles.tils.sortdata) > $@
 
-src/content/tils/feed.xml	src/content/tils/index.htmllisting:	src/content/tils/sortdata.txt	$(articles.tils.sortdata)
+src/content/tils/categories.txt	src/content/tils/feed.xml	src/content/tils/index.htmllisting:	src/content/tils/sortdata.txt	$(articles.tils.sortdata)
 src/content/tils/index.htmllisting:	$(articles.tils.indexentry)
-src/content/tils/feed.xml:	$(articles.tils.feedentry)
+src/content/tils/categories.txt:	$(articles.tils.categorydata)
+src/content/tils/categories.xml:	src/content/tils/categories.txt
+src/content/tils/categories.txt	src/content/tils/feed.xml:	$(articles.tils.feedentry)
diff --git a/mkdeps.sh b/mkdeps.sh
index 119b255..c02c483 100755
--- a/mkdeps.sh
+++ b/mkdeps.sh
@@ -36,12 +36,13 @@ files() {
 }
 
 
-pages                                       | varlist    'pages.adoc'
-articles                                    | varlist 'articles.adoc'
-listings                                    | varlist 'listings.adoc'
-listings | sed 's|/index\.adoc$|/feed.xml|' | varlist 'feeds.xml'
-find src/content/img/ -name '*.svg'         | varlist 'images.svg'
-extras                                      | varlist 'sources.extras'
+pages                                             | varlist    'pages.adoc'
+articles                                          | varlist 'articles.adoc'
+listings                                          | varlist 'listings.adoc'
+listings | sed 's|/index\.adoc$|/categories.txt|' | varlist 'categories.txt'
+listings | sed 's|/index\.adoc$|/feed.xml|'       | varlist 'feeds.xml'
+find src/content/img/ -name '*.svg'               | varlist 'images.svg'
+extras                                            | varlist 'sources.extras'
 
 
 files    | sed 's/^\(.*\)\.adoc$/\1.htmlbody\t\1.snippets\t\1.conf:\t\1.adoc/'
@@ -50,6 +51,7 @@ printf '\n'
 
 files    | sed 's/^\(.*\)\.adoc$/\1.html.gz:\t\1.html/'
 files    | sed 's/^\(.*\)\.adoc$/\1.snippets.gz:\t\1.snippets/'
+listings | sed 's|^\(.*\)/index\.adoc$|\1/categories.xml.gz:\t\1/categories.xml|'
 listings | sed 's|^\(.*\)/index\.adoc$|\1/feed.xml.gz:\t\1/feed.xml|'
 printf '\n'
 
@@ -60,6 +62,7 @@ printf '\n'
 
 articles | sed 's/^\(.*\)\.adoc$/\1.feedentry:\t\1.conf\t\1.htmlbody/'
 articles | sed 's/^\(.*\)\.adoc$/\1.sortdata:\t\1.conf/'
+articles | sed 's/^\(.*\)\.adoc$/\1.categorydata:\t\1.conf/'
 printf '\n'
 
 listings | sed 's/^\(.*\)\.adoc$/\1.htmlheader\t\1.htmlfooter:\t\1.conf/'
@@ -72,21 +75,23 @@ for colllink in src/collections/*; do
 	printf '\n\n'
 	name="$(basename "$c")"
 	find "$c"/*/ -type f -name '*.adoc' | varlist "articles.$name.adoc"
-	printf 'articles.%s.%s = $(articles.%s.adoc:.adoc=.%s)\n' \
-		"$name" 'sortdata  ' "$name" 'sortdata'
-	printf 'articles.%s.%s = $(articles.%s.adoc:.adoc=.%s)\n' \
-		"$name" 'indexentry' "$name" 'indexentry'
-	printf 'articles.%s.%s = $(articles.%s.adoc:.adoc=.%s)\n' \
-		"$name" 'feedentry ' "$name" 'feedentry'
+	art=articles # so things fit in 80 columns
+	echo "$art.$name.sortdata     = \$($art.$name.adoc:.adoc=.sortdata)"
+	echo "$art.$name.indexentry   = \$($art.$name.adoc:.adoc=.indexentry)"
+	echo "$art.$name.feedentry    = \$($art.$name.adoc:.adoc=.feedentry)"
+	echo "$art.$name.categorydata = \$($art.$name.adoc:.adoc=.categorydata)"
 
 
 	printf '%s/sortdata.txt:\tdeps.mk\n' "$c"
-	printf '\tprintf %s $(articles.%s.sortdata) > $@\n\n' \
-		"'%s\n'" "$name"
+	printf '\tprintf %s $(articles.%s.sortdata) > $@\n\n' "'%s\n'" "$name"
 
-	printf '%s/feed.xml\t%s/index.htmllisting:' "$c" "$c"
+	printf '%s/categories.txt\t%s/feed.xml\t%s/index.htmllisting:' \
+		"$c" "$c" "$c"
 	printf '\t%s/sortdata.txt\t$(articles.%s.sortdata)\n' "$c" "$name"
 
 	printf '%s/index.htmllisting:\t$(articles.%s.indexentry)\n' "$c" "$name"
-	printf '%s/feed.xml:\t$(articles.%s.feedentry)\n' "$c" "$name"
+	printf '%s/categories.txt:\t$(articles.%s.categorydata)\n' "$c" "$name"
+	printf '%s/categories.xml:\t%s/categories.txt\n' "$c" "$c"
+	printf '%s/categories.txt\t%s/feed.xml:\t$(articles.%s.feedentry)\n' \
+		"$c" "$c" "$name"
 done
diff --git a/src/content/podcasts/2020/12/19/test-entry.adoc b/src/content/podcasts/2020/12/19/test-entry.adoc
index 3302421..c641449 100644
--- a/src/content/podcasts/2020/12/19/test-entry.adoc
+++ b/src/content/podcasts/2020/12/19/test-entry.adoc
@@ -1,4 +1,5 @@
 = A test entry
+:categories: test
 
 audio: true
 
diff --git a/src/content/screencasts/2021/02/07/autoqemu.adoc b/src/content/screencasts/2021/02/07/autoqemu.adoc
index d7c9e12..440ede9 100644
--- a/src/content/screencasts/2021/02/07/autoqemu.adoc
+++ b/src/content/screencasts/2021/02/07/autoqemu.adoc
@@ -1,5 +1,6 @@
 = AutoQEMU - automate installation and SSH setup of ISO OS images
 :updatedat: 2022-03-06
+:categories: first
 
 :empty:
 :begriffs-tips: https://begriffs.com/posts/2020-08-31-portable-stable-software.html