21 files changed, 583 insertions, 182 deletions
diff --git a/.build.yml b/.build.yml
index 536f9e7..b8cf514 100644
--- a/.build.yml
+++ b/.build.yml
@@ -9,15 +9,20 @@ packages:
   - texinfo
   - gzip
 tasks:
-  - build: |
-      cd cpt
-      make
   - install-pax: |
       git clone --quiet https://github.com/carbslinux/otools
       cd otools
       ./configure
       make pax
       sudo install -Dm755 pax /usr/bin/pax
+  - install-blake3: |
+      git clone --quiet https://git.sr.ht/~mcf/b3sum
+      cd b3sum
+      sudo make PREFIX=/usr install
+  - build: |
+      cd cpt
+      ./configure
+      make
   - test: |
       cd cpt
       curl -fsSL https://git.io/shellspec | sudo sh -s -- -y -p /usr
diff --git a/.fossil-settings/ignore-glob b/.fossil-settings/ignore-glob
index d4cc917..98cdf27 100644
--- a/.fossil-settings/ignore-glob
+++ b/.fossil-settings/ignore-glob
@@ -17,3 +17,4 @@ tests/etc/cpt-hook
 .shellspec-quick.log
 report
 coverage
+config.mk
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7854cfe..5719efd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,39 @@ this project _somewhat_ adheres to [Semantic Versioning].
 [Semantic Versioning]: https://semver.org/spec/v2.0.0.html
 
 
+[Unreleased]
+--------------------------------------------------------------------------------
+
+### BLAKE3 checksums
+
+The package manager now uses `b3sum` for creating digests. The change is
+backwards compatible, which means that BLAKE3 will slowly replace the SHA256
+algorithm in packages. The `cpt` package in the repository will continue to use
+the sha256 until the end of 2021.
+
+The `checksums` files generated with BLAKE3 has the header `%BLAKE3` which is
+used to distinguish digest algorithms. If the file does not include such a
+header, it is assumed to be a file created using the SHA256 algorithm. This is
+especially handy for keeping the /etc checksums intact. If the package being
+built is already installed on the system `cpt` makes sure that the generated
+etcsums are also backwards compatible.
+
+
+### Added
+- `cpt-checksum` now has the `-s` flag to generate checksums using the SHA256
+  digest algorithm.
+- Added `CPT_DOWNLOADER` variable to change the download program. Available
+  options are: `curl`, `wget`, `wget2`, `aria2c`, and `axel`.
+- `cpt-chroot` now has the flag `-m` to disable mounting/unmounting pseudo
+  filesystems.
+- This changelog is now installed by the `Makefile`.
+
+### Changed
+- `cpt-size` has been rewritten to support POSIX `du`, and to support packages
+  with a file count of over 50,000.
+- Installation now requires to run `./configure`.
+
+
 6.1.1 - 2021-08-04
 --------------------------------------------------------------------------------
 
@@ -17,7 +50,7 @@ this project _somewhat_ adheres to [Semantic Versioning].
   the package manifest.
 
 
-6.1.0 - 2021-07-22
+[6.1.0] - 2021-07-22
 --------------------------------------------------------------------------------
 
 ### IMPORTANT
@@ -44,14 +77,14 @@ the next pull. The usage of the repository cache can be disabled by setting
 - Reworked the package repository backend.
 
 
-6.0.4 - 2021-05-12
+[6.0.4] - 2021-05-12
 --------------------------------------------------------------------------------
 
 ### Fixed
 - Fixed the declaration place of the `$pid` variable
 
 
-6.0.3 - 2021-05-10
+[6.0.3] - 2021-05-10
 --------------------------------------------------------------------------------
 
 ### Fixed
@@ -59,21 +92,21 @@ the next pull. The usage of the repository cache can be disabled by setting
 - Fixed `cpt --help` output when inside a directory prefixed with `cpt-`
 
 
-6.0.2 - 2021-04-05
+[6.0.2] - 2021-04-05
 --------------------------------------------------------------------------------
 
 ### Fixed
 - Fixed `make dist` target.
 
 
-6.0.1 - 2021-04-05
+[6.0.1] - 2021-04-05
 --------------------------------------------------------------------------------
 
 ### Fixed
 - Fixed inconsistencies of the `Ctrl+C` interrupt behaviour
 
 
-6.0.0 - 2021-04-03
+[6.0.0] - 2021-04-03
 --------------------------------------------------------------------------------
 
 ### Added
@@ -103,7 +136,7 @@ the next pull. The usage of the repository cache can be disabled by setting
 
 [ssu]: https://github.com/illiliti/ssu
 
-5.1.2 - 2021-01-04
+[5.1.2] - 2021-01-04
 --------------------------------------------------------------------------------
 
 ### Fixed
@@ -112,7 +145,7 @@ the next pull. The usage of the repository cache can be disabled by setting
   file locations on the manifest as well.
 
 
-5.1.1 - 2020-12-20
+[5.1.1] - 2020-12-20
 --------------------------------------------------------------------------------
 
 ### Fixed
@@ -120,7 +153,7 @@ the next pull. The usage of the repository cache can be disabled by setting
   `$CPT_DEBUG` was set
 
 
-5.1.0 - 2020-11-25
+[5.1.0] - 2020-11-25
 --------------------------------------------------------------------------------
 
 ### IMPORTANT
@@ -142,7 +175,7 @@ the next pull. The usage of the repository cache can be disabled by setting
   defined.
 
 
-5.0.0 - 2020-10-06
+[5.0.0] - 2020-10-06
 --------------------------------------------------------------------------------
 
 ### IMPORTANT
@@ -170,7 +203,7 @@ the next pull. The usage of the repository cache can be disabled by setting
   done in a `test` script can be done from the build itself.
 
 
-4.1.1 - 2020-09-25
+[4.1.1] - 2020-09-25
 --------------------------------------------------------------------------------
 
 ### Changed
@@ -184,7 +217,7 @@ the next pull. The usage of the repository cache can be disabled by setting
 - Fixed the `as_root()` function when using `su`.
 
 
-4.1.0 - 2020-09-11
+[4.1.0] - 2020-09-11
 --------------------------------------------------------------------------------
 
 ### Added
@@ -194,14 +227,14 @@ the next pull. The usage of the repository cache can be disabled by setting
 - Fixed `as_root()` call on `cpt-chbuild`.
 
 
-4.0.1 - 2020-09-10
+[4.0.1] - 2020-09-10
 --------------------------------------------------------------------------------
 
 ### Fixed
 - Fixed flags starting with `--no-`
 
 
-4.0.0 - 2020-09-09
+[4.0.0] - 2020-09-09
 --------------------------------------------------------------------------------
 
 With this update, all the documentation was moved to the `docs` repository,
@@ -229,14 +262,14 @@ which can be accessed from the following sources:
 - Fixed `getoptions` parsers while declaring initial variables.
 - Fixed build `cpt-stat` on the Makefile.
 
-3.3.1 - 2020-08-31
+[3.3.1] - 2020-08-31
 --------------------------------------------------------------------------------
 
 ### Changed
 - Reverted `sh256()` to the previous way.
 
 
-3.3.0 - 2020-08-31
+[3.3.0] - 2020-08-31
 --------------------------------------------------------------------------------
 
 ### Added
@@ -251,7 +284,7 @@ which can be accessed from the following sources:
 - Made `cpt` checksum method compatible with the KISS Community repository.
 
 
-3.2.0 - 2020-08-22
+[3.2.0] - 2020-08-22
 --------------------------------------------------------------------------------
 
 ### Added
@@ -268,14 +301,14 @@ which can be accessed from the following sources:
 - `cpt` programs no longer exit if `$CPT_PATH` is unset.
 
 
-3.1.1 - 2020-08-11
+[3.1.1] - 2020-08-11
 --------------------------------------------------------------------------------
 
 ### Changed
 - `as_root()` now sets package manager variables with env.
 
 
-3.1.0 - 2020-08-07
+[3.1.0] - 2020-08-07
 --------------------------------------------------------------------------------
 
 ### Changed
@@ -285,7 +318,7 @@ which can be accessed from the following sources:
 - Dropping libtool's `*.la` library files from packages.
 
 
-3.0.0 - 2020-07-24
+[3.0.0] - 2020-07-24
 --------------------------------------------------------------------------------
 
 This is the 3.0.0 release. This will make `kiss` (now renamed as `cpt`) a
@@ -323,7 +356,7 @@ comes with nice benefits such as:
 - Removed `kiss-outdated` and `kiss-which`.
 
 
-2.3.0 - 2020-07-16
+[2.3.0] - 2020-07-16
 --------------------------------------------------------------------------------
 
 ### Added
@@ -345,14 +378,14 @@ comes with nice benefits such as:
   package ownership.
 
 
-2.2.1 - 2020-06-11
+[2.2.1] - 2020-06-11
 --------------------------------------------------------------------------------
 
 ### Fixed
 - Fixed directory checking on package removal
 
 
-2.2.0 - 2020-06-10
+[2.2.0] - 2020-06-10
 --------------------------------------------------------------------------------
 
 ### Added
@@ -372,7 +405,7 @@ comes with nice benefits such as:
   characters (such as `/usr/bin/[`) would result in a manifest deletion.
 
 
-2.1.2 - 2020-06-03
+[2.1.2] - 2020-06-03
 --------------------------------------------------------------------------------
 
 ### Fixed
@@ -380,7 +413,7 @@ comes with nice benefits such as:
   the `passwd` database.
 
 
-2.1.1 - 2020-06-03
+[2.1.1] - 2020-06-03
 --------------------------------------------------------------------------------
 
 ### Fixed
@@ -389,7 +422,7 @@ comes with nice benefits such as:
 - Fixed setting binary packages as dependencies.
 
 
-2.1.0 - 2020-05-29
+[2.1.0] - 2020-05-29
 --------------------------------------------------------------------------------
 
 ### Added
@@ -404,7 +437,7 @@ comes with nice benefits such as:
 - Removed strip messages
 
 
-2.0.0 - 2020-05-28
+[2.0.0] - 2020-05-28
 --------------------------------------------------------------------------------
 
 ### Added
@@ -428,7 +461,7 @@ comes with nice benefits such as:
 [kiss-extra]: https://github.com/carbslinux/kiss-extra
 
 
-1.22.4 - 2020-05-26
+[1.22.4] - 2020-05-26
 --------------------------------------------------------------------------------
 
 **NOTE:** `1.22.x` is the last minor version before `2.0.0`, meaning I will not
@@ -445,7 +478,7 @@ before release, as binary repositories will need user feedback.
 - Enabled the usage of glob characters for `kiss-bin`.
 
 
-1.22.3 - 2020-05-18
+[1.22.3] - 2020-05-18
 --------------------------------------------------------------------------------
 
 ### SECURITY
@@ -457,7 +490,7 @@ before release, as binary repositories will need user feedback.
 [related proof-of-concept]: https://github.com/kisslinux/kiss/pull/157#issuecomment-629880775
 
 
-1.22.2 - 2020-05-16
+[1.22.2] - 2020-05-16
 --------------------------------------------------------------------------------
 
 ### Fixed
@@ -466,7 +499,7 @@ before release, as binary repositories will need user feedback.
 
 
 
-1.22.1 - 2020-05-15
+[1.22.1] - 2020-05-15
 --------------------------------------------------------------------------------
 
 ### REMOVED
@@ -492,7 +525,7 @@ before release, as binary repositories will need user feedback.
 [kiss-extra]: https://github.com/carbslinux/kiss-extra
 
 
-1.22.0 - 2020-05-14
+[1.22.0] - 2020-05-14
 --------------------------------------------------------------------------------
 
 ### Added
@@ -511,7 +544,7 @@ before release, as binary repositories will need user feedback.
   full file.
 
 
-1.21.1 - 2020-05-14
+[1.21.1] - 2020-05-14
 --------------------------------------------------------------------------------
 
 ### Changed
@@ -523,7 +556,7 @@ before release, as binary repositories will need user feedback.
 - Fixed a non-POSIX `find` call. Thanks to @illiliti.
 
 
-1.21.0 - 2020-05-12
+[1.21.0] - 2020-05-12
 --------------------------------------------------------------------------------
 
 ### Added
@@ -547,7 +580,7 @@ before release, as binary repositories will need user feedback.
   external utilities.
 
 
-1.20.3 - 2020-05-09
+[1.20.3] - 2020-05-09
 --------------------------------------------------------------------------------
 
 ### Fixed
@@ -555,14 +588,14 @@ before release, as binary repositories will need user feedback.
   moving to `/var/db/kiss/choices` would take the name of the preferred package.
 
 
-1.20.2 - 2020-05-09
+[1.20.2] - 2020-05-09
 --------------------------------------------------------------------------------
 
 ### Fixed
 - Fixed an issue regarding manifest format when using pkg_swap (alternatives).
 
 
-1.20.1 - 2020-05-08
+[1.20.1] - 2020-05-08
 --------------------------------------------------------------------------------
 
 ### Changed
@@ -570,14 +603,14 @@ before release, as binary repositories will need user feedback.
 - Standardised `kiss-readlink` usage output.
 
 
-1.20.0 - 2020-05-07
+[1.20.0] - 2020-05-07
 --------------------------------------------------------------------------------
 
 ### Added
 - `KISS_NOPROMPT` can be specified in order to skip prompts.
 
 
-1.19.1 - 2020-05-07
+[1.19.1] - 2020-05-07
 --------------------------------------------------------------------------------
 
 ### Added
@@ -593,7 +626,7 @@ before release, as binary repositories will need user feedback.
   globally.
 
 
-1.19.0 - 2020-05-06
+[1.19.0] - 2020-05-06
 --------------------------------------------------------------------------------
 
 ### Added
@@ -613,7 +646,7 @@ before release, as binary repositories will need user feedback.
   `kiss extensions`.
 
 
-1.18.0 - 2020-05-04
+[1.18.0] - 2020-05-04
 --------------------------------------------------------------------------------
 
 ### Added
@@ -631,7 +664,7 @@ before release, as binary repositories will need user feedback.
 - Dropped the usage of `readlink` in `kiss`.
 
 
-1.17.0 - 2020-05-03
+[1.17.0] - 2020-05-03
 --------------------------------------------------------------------------------
 
 ### Added
@@ -652,14 +685,14 @@ before release, as binary repositories will need user feedback.
   `ksh` compatibility.
 
 
-1.16.3 - 2020-05-03
+[1.16.3] - 2020-05-03
 --------------------------------------------------------------------------------
 
 ### Fixed
 - Fixed etcsum location.
 
 
-1.16.2 - 2020-05-03
+[1.16.2] - 2020-05-03
 --------------------------------------------------------------------------------
 
 ### Added
@@ -676,14 +709,14 @@ before release, as binary repositories will need user feedback.
   system.
 
 
-1.16.1 - 2020-05-01
+[1.16.1] - 2020-05-01
 --------------------------------------------------------------------------------
 
 ### Fixed
 - Fixed `ksh` Ctrl+C interrupt signals.
 
 
-1.16.0 - 2020-05-01
+[1.16.0] - 2020-05-01
 --------------------------------------------------------------------------------
 
 ### Added
@@ -699,7 +732,7 @@ before release, as binary repositories will need user feedback.
   `$KISS_ROOT` variable
 
 
-1.15.0 - 2020-04-30
+[1.15.0] - 2020-04-30
 --------------------------------------------------------------------------------
 
 I have decided to revert to rsync installation method as it is faster and safer.
@@ -715,14 +748,14 @@ at the trade-off.
 - `kiss` now accepts decompressed tar archives for package installation as well.
 
 
-1.14.2/1.14.3 - 2020-04-27
+[1.14.2/1.14.3] - 2020-04-27
 --------------------------------------------------------------------------------
 
 ### Fixed
 - The new installation method now complies to the `$KISS_ROOT` value.
 
 
-1.14.1 - 2020-04-27
+[1.14.1] - 2020-04-27
 --------------------------------------------------------------------------------
 
 ### Removed
@@ -736,7 +769,7 @@ at the trade-off.
 - Whitespace cleanup.
 
 
-1.14.0 - 2020-04-25
+[1.14.0] - 2020-04-25
 --------------------------------------------------------------------------------
 
 This release removes `rsync` from `kiss` and implements its own installation
@@ -754,14 +787,14 @@ method.
 - usage of `old_ifs`
 
 
-1.13.1 - 2020-04-19
+[1.13.1] - 2020-04-19
 --------------------------------------------------------------------------------
 
 ### Removed
 - Reverted and removed `kiss ss` changes.
 
 
-1.13.0 - 2020-04-19
+[1.13.0] - 2020-04-19
 --------------------------------------------------------------------------------
 
 ### Added
@@ -776,7 +809,7 @@ method.
 - Fixed a shellcheck error.
 
 
-1.12.3 - 2020-04-17
+[1.12.3] - 2020-04-17
 --------------------------------------------------------------------------------
 
 ### Changed
@@ -787,7 +820,7 @@ method.
 - `kiss-repodepends` now outputs the proper depends file.
 
 
-1.12.2 - 2020-04-15
+[1.12.2] - 2020-04-15
 --------------------------------------------------------------------------------
 
 ### Added
@@ -802,14 +835,14 @@ method.
 - `kiss-export` now honours your `KISS_COMPRESS` value
 
 
-1.12.1 - 2020-04-12
+[1.12.1] - 2020-04-12
 --------------------------------------------------------------------------------
 
 ### Fixed
 - Fixed printing empty arguments in `kiss-outdated`.
 
 
-1.12.0 - 2020-04-05
+[1.12.0] - 2020-04-05
 --------------------------------------------------------------------------------
 
 ### Added
@@ -829,7 +862,7 @@ method.
   it could lead to wrong url generation.
 
 
-1.9.0 - 1.11.2 - 2020-04-04
+[1.9.0 - 1.11.2] - 2020-04-04
 --------------------------------------------------------------------------------
 
 ### Added
diff --git a/Makefile b/Makefile
index eceb18d..b2c7a5f 100644
--- a/Makefile
+++ b/Makefile
@@ -1,33 +1,45 @@
 # Carbs Packaging Tools
-include config.mk
+-include config.mk
 
 INSTALL_SH = ./tools/install.sh
 CONTRIB = `find contrib -name 'cpt*' ! -name '*.*'`
 SRC     = `find src -name 'cpt*' ! -name '*.*'`
 BIN     = ${SRC} ${CONTRIB}
-LIB        = src/cpt-lib
-LIB_IN     = ${LIB:=.in}
 
 all: src/cpt-lib
-	test "${DOCS}" != yes || ${MAKE} -C docs all
+	@if ! [ -e config.mk ]; then echo "Please run './configure'"; exit 1; fi
+	@test "${DOCS}" != yes || ${MAKE} -C docs all
 
 src/cpt-lib: src/cpt-lib.in
-	sed -e "s|@VERSION@|${VERSION}|g" \
-		-e "s|@DOCSTRING@|Call functions from the library|g" < src/cpt-lib.in > $@
+	sed -n '/^Copyright/{s,^,        ",;s,$$," \\,;p}' LICENSE | \
+	sed -e '/@LICENSE@/r /dev/stdin' \
+		-e '/@LICENSE@/d' \
+		-e "s|@VERSION@|${VERSION}|g" \
+		-e "s|@DOCSTRING@|Call functions from the library|g" src/cpt-lib.in > $@
 	chmod 755 $@
 
-test: all tests/etc/cpt-hook
+shellspec: all tests/etc/cpt-hook
 	shellspec
+
+shellcheck: all
 	cd src; find . ../contrib -name 'cpt*' ! -name '*.*' -exec shellcheck -e 2119 -x -f gcc {} +
 
+test: shellspec shellcheck
+
 tests/etc/cpt-hook:
 	ln -s ../hook-file $@
 
 dist: docs/cpt.info
+	@if ! [ -e config.mk ]; then echo "Please run './configure'"; exit 1; fi
 	./tools/mkdist.sh "${VERSION}"
 
 install: all
 	test "${DOCS}" != yes || ${MAKE} -C docs install
+	[ -f docs/cpt.info ] && \
+		${INSTALL_SH} -Dm644 docs/cpt.info ${DESTDIR}${INFODIR}/cpt.info
+	[ -f docs/cpt.txt ] && \
+		${INSTALL_SH} -Dm644 docs/cpt.txt  ${DESTDIR}${DOCDIR}/cpt.txt
+	${INSTALL_SH} -Dm644 CHANGELOG.md  ${DESTDIR}${DOCDIR}/CHANGELOG
 	${INSTALL_SH} -Dm755 -t ${DESTDIR}${BINDIR} ${BIN}
 	${INSTALL_SH} -Dm644 -t ${DESTDIR}${MAN1} man/*.1
 	for man in ${CONTRIB}; do \
@@ -36,15 +48,19 @@ install: all
 	done
 
 uninstall:
-	test "${DOCS}" != yes || ${MAKE} -C docs uninstall
 	for bin in ${BIN}; do \
 		rm -f ${DESTDIR}${BINDIR}/$${bin##*/}; done
 	for man in man/*.1; do rm -f ${DESTDIR}${MAN1}/$${man##*/}; done
 	for man in ${CONTRIB}; do rm -f ${DESTDIR}${MAN1}/$${man##*/}.1; done
+	rm -rf ${DESTDIR}${DOCDIR}
+	rm -f  ${DESTDIR}${INFODIR}/cpt.info
 
 clean:
-	test "${DOCS}" != yes || ${MAKE} -C docs clean
+	${MAKE} -C docs clean
 	rm -rf src/cpt-lib "cpt-${VERSION}.tar.xz" coverage report
 	rm -f tests/etc/cpt-hook
 
-.PHONY: all dist clean install uninstall
+allclean: clean
+	rm -f config.mk
+
+.PHONY: all dist allclean clean install uninstall shellspec shellcheck test
diff --git a/README b/README.md
index 6e78b2a..e5a5580 100644
--- a/README
+++ b/README.md
@@ -1,8 +1,15 @@
 Carbs Packaging Tools
 =====================
 
-Package management toolset for Carbs Linux. Forked from KISS[1]. All usage
-information can be obtained from the manual page. Refer to the ChangeLog[2] to
+    ##### ####  #####
+    #   # #   #   #
+    #     ####    #
+    #   # #       #
+    ##### #       #
+
+
+Package management toolset for Carbs Linux. Forked from [KISS]. All usage
+information can be obtained from the manual page. Refer to the [ChangeLog] to
 learn what's new.
 
 
@@ -36,10 +43,11 @@ either passing `DOCS=no` to `make` or editing `config.mk` to disable it.
 Installation
 ------------
 
-In order to install CPT, you can run the following with `make`:
+In order to install CPT, you can run the following:
 
+    ./configure
     make
-    make PREFIX=/usr install
+    make install
 
 
 Documentation
@@ -47,12 +55,12 @@ Documentation
 
 The documentation for each tool along with some examples can be found on
 manpages installed with the package manager. User manual of CPT can be found
-online[3], or installed as both plain-text and as info pages. Without any
+[online], or installed as both plain-text and as info pages. Without any
 changes to the Makefile configuration those files can be found at:
 
 - /usr/local/share/docs/cpt/cpt.txt
 - /usr/local/share/info/cpt.info
 
-[1]: https://github.com/kisslinux/kiss
-[2]: https://fossil.carbslinux.org/cpt/log
-[3]: https://carbslinux.org/docs/cpt
+[KISS]: https://github.com/kisslinux/kiss
+[ChangeLog]: https://fossil.carbslinux.org/cpt/doc/trunk/CHANGELOG.md
+[online]: https://carbslinux.org/docs/cpt
diff --git a/config.mk b/config.mk
deleted file mode 100644
index a165463..0000000
--- a/config.mk
+++ /dev/null
@@ -1,18 +0,0 @@
-# Carbs Packaging Tools
-VERSION = 6.1.1
-
-# Installation paths
-PREFIX    = /usr/local
-BINDIR    = ${PREFIX}/bin
-SHAREDIR  = ${PREFIX}/share
-INFODIR   = ${SHAREDIR}/info
-DOCDIR    = ${SHAREDIR}/doc
-CPTDOC    = ${DOCDIR}/cpt
-MANPREFIX = ${SHAREDIR}/man
-MAN1      = ${MANPREFIX}/man1
-
-EMACS     = emacs
-MAKEINFO  = makeinfo
-
-# Comment or change if you don't want to build/install the documentation
-DOCS = yes
diff --git a/configure b/configure
new file mode 100755
index 0000000..a2d0bba
--- /dev/null
+++ b/configure
@@ -0,0 +1,112 @@
+#!/bin/sh -e
+
+version=Fossil
+
+die() {
+    printf '%s: %s\n' "${0##*/}" "$*" >&2
+    exit 1
+}
+
+out() { printf '%s\n' "$@" ;}
+
+_check() {
+    for arg; do
+        printf 'checking for %s... ' "$arg"
+        command -v "$arg" || { out no; die "'$arg' not found" ;}
+    done
+}
+
+_check_multi() {
+    c=$1; shift
+    printf 'checking for %s... ' "$c"
+    for arg; do command -v "$arg" && return 0; done
+    out no; die "no $c was found"
+}
+
+usage() {
+    out "usage: $0 [options]" \
+        "Options:" \
+        "  --prefix=dir        Set prefix directory" \
+        "  --bindir=dir        User executables [PREFIX/bin]" \
+        "  --datarootdir=dir   Data root directory [PREFIX/share]" \
+        "  --mandir=dir        Manual pages [DATAROOTDIR/man]" \
+        "  --infodir=dir       info documentation [DATAROOTDIR/info]" \
+        "  --docdir=dir        Documentation directory [DATAROOTDIR/doc/cpt]" \
+        "  --with-docs=opt     Whether to build the texinfo documentation [auto]" "" \
+        "  MAKEINFO            Name of the 'makeinfo' executable" \
+        "  EMACS               Name of the 'emacs' executable" "" \
+        "Use these variables to override the behaviour of '$0'."
+    exit 1
+}
+
+prefix=/usr/local
+# We don't want expansion
+# shellcheck disable=2016
+{
+bindir='$(PREFIX)/bin'
+datarootdir='$(PREFIX)/share'
+mandir='$(DATAROOTDIR)/man'
+infodir='$(DATAROOTDIR)/info'
+docdir='$(DATAROOTDIR)/doc/cpt'
+}
+docs=auto
+
+for arg; do
+    case $arg in
+        -h|--help) usage ;;
+        --prefix=*) prefix=${arg#*=}   ;;
+        --bindir=*) bindir=${arg#*=}   ;;
+        --mandir=*) mandir=${arg#*=}   ;;
+        --infodir=*) infodir=${arg#*=} ;;
+        --docdir=*) docdir=${arg#*=}   ;;
+        --without-docs) docs=no        ;;
+        --with-docs)    docs=yes       ;;
+        --with-docs=*)  docs=${arg#*=} ;;
+        *-*) die "Unknown option: '$arg'" ;;
+        *=*) export "${arg:?}" ;;
+        *) die "Unknown argument: '$arg'"
+    esac
+done
+
+trap 'rm -f config.mk' EXIT
+trap 'rm -f config.mk; exit 1' INT
+
+: "${EMACS:=emacs}" "${MAKEINFO:=makeinfo}"
+
+out "starting configuration..."
+
+cat <<EOF > config.mk
+PREFIX = $prefix
+BINDIR = $bindir
+DATAROOTDIR = $datarootdir
+MANDIR  = $mandir
+INFODIR = $infodir
+DOCDIR  = $docdir
+MAN1    = \$(MANDIR)/man1
+
+VERSION = $version
+EMACS   = $EMACS
+EOF
+
+case $docs in
+    auto|yes)
+        printf 'checking for makeinfo... '
+        if makeinfo=$(command -v "$MAKEINFO"); then
+            out "$makeinfo"
+            docs=yes
+            out "MAKEINFO = $makeinfo" >>config.mk
+        else
+            out no
+            [ "$docs" = yes ] && die "'$MAKEINFO' not found"
+            docs=no
+        fi
+esac
+[ "$docs" = no ] && out "not building documentation"
+out "DOCS = $docs" >>config.mk
+
+out "checking runtime dependencies"
+_check pax rsync sed awk grep b3sum
+_check_multi "sha256 provider" sha256sum sha256 openssl
+
+trap - EXIT INT
+out "written config.mk" "Run 'make' to build cpt"
diff --git a/contrib/cpt-chroot b/contrib/cpt-chroot
index 2f7eee7..a2ea151 100755
--- a/contrib/cpt-chroot
+++ b/contrib/cpt-chroot
@@ -1,22 +1,88 @@
 #!/bin/sh -e
 # Enter a chroot
+# shellcheck disable=2004
 
 ## SYNOPSIS:
 ## .Nm cpt-chroot
+## .Op Fl m
 ## .Op Ar dir
 
 ## DESCRIPTION:
 ## .Nm
 ## is a wrapper script to chroot inside other root filesystems. It automatically
 ## mounts important filesystems in to the chroot directory, and unmounts them
-## when the user exits the chroot and cleans up leftover host files.
+## when the user exits the chroot and cleans up leftover host files. If the flag
+## .Fl m
+## is given,
+## .Nm
+## does not try to mount or unmount any filesystems.
+
+# We generate the parser into the script, because we don't want this script to
+# depend on cpt-lib.
+nomount=''
+REST=''
+parse() {
+    OPTIND=$(($#+1))
+    while OPTARG= && [ $# -gt 0 ]; do
+        case $1 in
+            --?*=*) OPTARG=$1; shift
+                    eval 'set -- "${OPTARG%%\=*}" "${OPTARG#*\=}"' ${1+'"$@"'}
+                    ;;
+            --no-*) unset OPTARG ;;
+            -[mh]?*) OPTARG=$1; shift
+                     eval 'set -- "${OPTARG%"${OPTARG#??}"}" -"${OPTARG#??}"' ${1+'"$@"'}
+                     OPTARG= ;;
+        esac
+        case $1 in
+            '-m')
+                [ "${OPTARG:-}" ] && OPTARG=${OPTARG#*\=} && set "noarg" "$1" && break
+                eval '[ ${OPTARG+x} ] &&:' && OPTARG='1' || OPTARG=''
+                nomount="$OPTARG"
+                ;;
+            '-h'|'--help')
+                usage
+                exit 0 ;;
+            --)
+                shift
+                while [ $# -gt 0 ]; do
+                    REST="${REST} \"\${$(($OPTIND-$#))}\""
+                    shift
+                done
+                break ;;
+            [-]?*)
+                set "unknown" "$1"; break ;;
+            *)
+                REST="${REST} \"\${$(($OPTIND-$#))}\""
+        esac
+        shift
+    done
+    [ $# -eq 0 ] && { OPTIND=1; unset OPTARG; return 0; }
+    case $1 in
+        unknown) set "Unrecognized option: $2" "$@" ;;
+        noarg) set "Does not allow an argument: $2" "$@" ;;
+        required) set "Requires an argument: $2" "$@" ;;
+        pattern:*) set "Does not match the pattern (${1#*:}): $2" "$@" ;;
+        notcmd) set "Not a command: $2" "$@" ;;
+        *) set "Validation error ($1): $2" "$@"
+    esac
+    echo "$1" >&2
+    exit 1
+}
+usage() { printf '%s\n' "usage: ${0##*/} [-m] [dir]" "" "Options:" \
+    "  -m                          Don't mount or unmount directories"
+}
+
+parser_definition() {
+    setup REST help:usage -- "usage: ${0##*/} [-m] [dir]"
+    msg -- '' 'Options:'
+    flag nomount -m        -- "Don't mount or unmount directories"
+    disp :usage  -h --help hidden:1
+}
 
 log() {
     printf '\033[32m->\033[m %s.\n' "$*"
 }
 
-usage() { printf '%s [dir]\n' "${0##*/}"; exit 0;}
-
 die() {
     log "$*" >&2
     exit 1
@@ -35,7 +101,7 @@ clean() {
 }
 
 main() {
-    case "$1" in ''|--help|-h) usage; esac
+    parse "$@" && eval set -- "$REST"
     [ -d "$1" ]        || die Given path does not exist
     [ "$(id -u)" = 0 ] || die Script needs to be run as root
 
@@ -48,17 +114,19 @@ main() {
         esac
     }
 
-    trap 'clean "$1"' EXIT INT
+    [ -z "$nomount" ] && {
+        trap 'clean "$1"' EXIT INT
 
-    log Mounting /dev, /proc and /sys from host; {
-        mountpoint -q "$1/dev"  || mount -o bind /dev "$1/dev"
-        mountpoint -q "$1/proc" || mount -t proc proc "$1/proc"
-        mountpoint -q "$1/sys"  || mount -t sysfs sys "$1/sys"
+        log Mounting /dev, /proc and /sys from host; {
+            mountpoint -q "$1/dev"  || mount -o bind /dev "$1/dev"
+            mountpoint -q "$1/proc" || mount -t proc proc "$1/proc"
+            mountpoint -q "$1/sys"  || mount -t sysfs sys "$1/sys"
 
-    }
+        }
 
-    log Copying /etc/resolv.conf from host; {
-         [ -f "$1/etc/resolv.conf" ] || cp /etc/resolv.conf "$1/etc"
+        log Copying /etc/resolv.conf from host; {
+            [ -f "$1/etc/resolv.conf" ] || cp /etc/resolv.conf "$1/etc"
+        }
     }
 
     log Entering chroot; {
diff --git a/contrib/cpt-size b/contrib/cpt-size
index 2812d56..4b983a1 100755
--- a/contrib/cpt-size
+++ b/contrib/cpt-size
@@ -11,40 +11,41 @@
 ## .Ar packages
 ## using the files from the package manifest and outputs a total size of the
 ## packages along with all the files associated with them.
+parser_definition() {
+    setup REST help:usage -- "usage: ${0##*/} [pkg...]"
+    disp :usage -h --help hidden:1
+}
 
-## CAVEATS:
-## .Nm
-## uses the non-POSIX
-## .Fl h
-## and
-## .Fl c
-## flags for
-## .Xr du 1 ,
-## which will not work with
-## .Em sbase ,
-## but it is a major performance improvement compared to calculating
-## total and human-readable sizes by hand.
+# shellcheck source=../src/cpt-lib
+# shellcheck disable=1091
+. cpt-lib
 
-case "$1" in
-    --help|-h)
-        printf '%s\n' "usage: ${0##*/} [pkg...]"
-        exit 0
-        ;;
-    '') set -- "${PWD##*/}"
-esac
+# Ensure that all the packages given as arguments are installed.
+pkg_list "$@" >/dev/null
 
-for pkg; do cpt-list "$pkg" >/dev/null; done
+mkdir -p "$tmp_dir"
 
-files=
-for pkg; do
-    while read -r file; do
-        # Filter directories from manifest and leave only files.
-        # Directories in the manifest end in a trailing '/'.
-        case $file in */) continue; esac
-        files="$files '$file'"
-    done < "$CPT_ROOT/var/db/cpt/installed/$pkg/manifest"
-done
-eval "set -- $files"
+# We don't immediately pipe into awk as we want to exit in an error.
+for pkg; do sed '/\/$/d;s/./\\&/g' "$sys_db/$pkg/manifest"; done |
+    xargs du -k > "$tmp_dir/size"
 
-# Send the file list to 'du'.
-du -shc -- "$@" 2>/dev/null
+# This awk function formats the `du` output similar to the '-hc' flags. We
+# could have used a shell `while read` loop to do the exact same thing, but that
+# would be much much slower.
+awk 'function fmtsize(s) {
+         if (s==0) f=""
+         else if (s<1024) f="K"
+         else if (s<(1048576)){f="M";s=s/1024;}
+         else if (s<(1073741824)){f="G";s=s/1048576;}
+         else f=""
+         return int(s) f
+     }
+     {
+         sc = $1
+         size += $1
+         sub(sprintf("^%s\s*", $1), "")
+         printf("%-6s %s\n", fmtsize(sc), $0)
+     }
+     END {
+         printf("%-6s total\n", fmtsize(size))
+     }' "$tmp_dir/size"
diff --git a/docs/Makefile b/docs/Makefile
index 344bd70..3a7dbf0 100644
--- a/docs/Makefile
+++ b/docs/Makefile
@@ -1,5 +1,5 @@
 # Carbs Packaging Tools Documentation
-include ../config.mk
+-include ../config.mk
 INSTALL_SH = ../tools/install.sh
 
 all: cpt.txt cpt.texi cpt.info
@@ -22,12 +22,4 @@ clean:
 all-clean: clean
 	rm -f cpt.texi cpt.txt
 
-install: all
-	${INSTALL_SH} -Dm644 cpt.txt ${DESTDIR}${CPTDOC}/cpt.txt
-	${INSTALL_SH} -Dm644 cpt.info ${DESTDIR}${INFODIR}/cpt.info
-
-uninstall:
-	rm -rf ${DESTDIR}${CPTDOC}
-	rm -f  ${DESTDIR}${INFODIR}/cpt.info
-
 .PHONY: all clean all-clean install uninstall
diff --git a/docs/cpt.org b/docs/cpt.org
index 7496ec9..263c547 100644
--- a/docs/cpt.org
+++ b/docs/cpt.org
@@ -184,6 +184,11 @@ to provide detailed information.
   #+VINDEX: CPT_DEBUG
   If set to 1, temporary directories will not be removed after the operation.
 
+- ~CPT_DOWNLOADER~ ::
+
+  The tool to be used to download package sources. One of =curl=, =wget=,
+  =wget2=, =axel=, =aria2c=. Defaults to the first one found in that order.
+
 - ~CPT_FETCH~ ::
 
   #+VINDEX: CPT_FETCH
@@ -433,6 +438,21 @@ of the package maintainer. Everything in the package directory will also be
 added to the package database that is located on =/var/db/cpt/installed=. These
 can be patches, configuration files, etc.
 
+Below is a table that provides a small summary for each file, see the relevant
+section to learn detailed information on each of them.
+
+| File         | Language                           | Executable | Mandatory |
+|--------------+------------------------------------+------------+-----------|
+| build        | any                                | yes        | yes       |
+| checksums    | generated by =cpt-checksum=        | no         | no        |
+| meta         | key-value pairs as in RFC822[fn:1] | no         | no[fn:2]  |
+| depends      | custom format                      | no         | no        |
+| sources      | custom format                      | no         | no        |
+| version      | custom format                      | no         | yes       |
+| message      | plaintext                          | no         | no        |
+| post-install | any                                | yes        | no        |
+| test         | any                                | yes        | no        |
+
 ** build
 :PROPERTIES:
 :DESCRIPTION: The build script
@@ -506,7 +526,7 @@ the sha256 algorithm.
 
 ** version
 :PROPERTIES:
-:DESCRIPTION: The file containing the version and the release numbers of a package
+:DESCRIPTION: The file containing version information for a package
 :END:
 
 The version file includes the version of the software and the release number of
@@ -1233,3 +1253,9 @@ MIT
 
 * {{{index(Concept, cp)}}}
 * {{{index(Variable,vr)}}}
+
+* Footnotes
+
+[fn:1] https://datatracker.ietf.org/doc/html/rfc822#section-3.2
+[fn:2] Not mandatory for the packaging system, but mandatory for inclusion in
+the repositories
diff --git a/docs/cpt.texi b/docs/cpt.texi
index 8bdcd99..7487209 100644
--- a/docs/cpt.texi
+++ b/docs/cpt.texi
@@ -77,7 +77,7 @@ Packaging System
 * build::                        The build script
 * sources::                      The file containing package sources
 * checksums::                    The file containing sha256sum of the sources
-* version::                      The file containing the version and the release numbers of a package
+* version::                      The file containing version information for a package
 * depends::                      The file containing the dependencies of a package
 * meta::                         File containing more information on packages
 * post-install::                 The post-installation script
@@ -299,6 +299,10 @@ set to 0, they will be forced to display them without colours. Otherwise,
 @vindex CPT_DEBUG
 If set to 1, temporary directories will not be removed after the operation.
 
+@item @code{CPT_DOWNLOADER}
+The tool to be used to download package sources. One of @samp{curl}, @samp{wget},
+@samp{wget2}, @samp{axel}, @samp{aria2c}. Defaults to the first one found in that order.
+
 @item @code{CPT_FETCH}
 @vindex CPT_FETCH
 If set to 0, @code{cpt-update} will not fetch repositories.
@@ -559,11 +563,58 @@ of the package maintainer. Everything in the package directory will also be
 added to the package database that is located on @samp{/var/db/cpt/installed}. These
 can be patches, configuration files, etc.
 
+Below is a table that provides a small summary for each file, see the relevant
+section to learn detailed information on each of them.
+
+@multitable {aaaaaaaaaaaa} {aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa} {aaaaaaaaaa} {aaaaaaaaa}
+@headitem File
+@tab Language
+@tab Executable
+@tab Mandatory
+@item build
+@tab any
+@tab yes
+@tab yes
+@item checksums
+@tab generated by @samp{cpt-checksum}
+@tab no
+@tab no
+@item meta
+@tab key-value pairs as in RFC822@footnote{@uref{https://datatracker.ietf.org/doc/html/rfc822#section-3.2}}
+@tab no
+@tab no@footnote{Not mandatory for the packaging system, but mandatory for inclusion in
+the repositories}
+@item depends
+@tab custom format
+@tab no
+@tab no
+@item sources
+@tab custom format
+@tab no
+@tab no
+@item version
+@tab custom format
+@tab no
+@tab yes
+@item message
+@tab plaintext
+@tab no
+@tab no
+@item post-install
+@tab any
+@tab yes
+@tab no
+@item test
+@tab any
+@tab yes
+@tab no
+@end multitable
+
 @menu
 * build::                        The build script
 * sources::                      The file containing package sources
 * checksums::                    The file containing sha256sum of the sources
-* version::                      The file containing the version and the release numbers of a package
+* version::                      The file containing version information for a package
 * depends::                      The file containing the dependencies of a package
 * meta::                         File containing more information on packages
 * post-install::                 The post-installation script
diff --git a/docs/cpt.txt b/docs/cpt.txt
index 550a6a3..8934c15 100644
--- a/docs/cpt.txt
+++ b/docs/cpt.txt
@@ -244,6 +244,11 @@ development manual for *Carbs Packaging Tools*. For development logs see
         If set to 1, temporary directories will not be removed after the
         operation.
 
+  `CPT_DOWNLOADER'
+        The tool to be used to download package sources. One of `curl',
+        `wget', `wget2', `axel', `aria2c'. Defaults to the first one
+        found in that order.
+
   `CPT_FETCH'
         If set to 0, `cpt-update' will not fetch repositories.
 
@@ -480,6 +485,21 @@ development manual for *Carbs Packaging Tools*. For development logs see
   on `/var/db/cpt/installed'. These can be patches, configuration files,
   etc.
 
+  Below is a table that provides a small summary for each file, see the
+  relevant section to learn detailed information on each of them.
+
+   File          Language                         Executable  Mandatory 
+  ----------------------------------------------------------------------
+   build         any                              yes         yes       
+   checksums     generated by `cpt-checksum'      no          no        
+   meta          key-value pairs as in RFC822[1]  no          no[2]     
+   depends       custom format                    no          no        
+   sources       custom format                    no          no        
+   version       custom format                    no          yes       
+   message       plaintext                        no          no        
+   post-install  any                              yes         no        
+   test          any                              yes         no        
+
 
 5.1 build
 ~~~~~~~~~
@@ -1300,3 +1320,13 @@ development manual for *Carbs Packaging Tools*. For development logs see
 
 
 [meta file] See section 5.6
+
+
+
+Footnotes
+_________
+
+[1] <https://datatracker.ietf.org/doc/html/rfc822#section-3.2>
+
+[2] Not mandatory for the packaging system, but mandatory for
+inclusion in the repositories
diff --git a/man/cpt-checksum.1 b/man/cpt-checksum.1
index 4c637eb..bfced46 100644
--- a/man/cpt-checksum.1
+++ b/man/cpt-checksum.1
@@ -5,15 +5,27 @@
 .Nd generate checksums
 .Sh SYNOPSIS
 .Nm
+.Op Fl s
 .Op Ar package...
 .Sh DESCRIPTION
 .Nm
-lints a package, downloads the sources, and creates a checksum file
-including the SHA256 digests of the sources. If no
+lints a package, downloads the sources, and creates a file named
+.Sq checksums
+which includes the
+.Em BLAKE3
+digests of the sources. If no
 .Ar package
 is specified,
 .Nm
 will generate checksums assuming the working directory as the package.
+.Pp
+If the
+.Fl s
+flag is given,
+.Nm
+will generate checksums using the
+.Em SHA256
+algorithm.
 .Sh AUTHOR
 .An Cem Keylan Aq Mt cem@ckyln.com
 .Sh LICENSE
diff --git a/spec/01_lib_spec.sh b/spec/01_lib_spec.sh
index 113d517..b56ac32 100644
--- a/spec/01_lib_spec.sh
+++ b/spec/01_lib_spec.sh
@@ -14,7 +14,7 @@ Describe 'CPT Library'
         VERSION=$(sed -n '/VERSION/s/.* //gp' config.mk)
         It 'prints version information'
             When run script src/cpt-lib version
-            The stderr should eq "-> Carbs Packaging Tools $VERSION"
+            The line 1 of stdout should eq "Carbs Packaging Tools, version $VERSION"
         End
     End
     Describe 'text functions'
diff --git a/spec/02_src_spec.sh b/spec/02_src_spec.sh
index 4685ec1..be81775 100644
--- a/spec/02_src_spec.sh
+++ b/spec/02_src_spec.sh
@@ -13,7 +13,7 @@ Describe 'Main toolchain'
             VERSION=$(sed -n '/VERSION/s/.* //gp' config.mk)
             It 'outputs cpt version'
                 When run script src/cpt --version
-                The stderr should eq "-> Carbs Packaging Tools $VERSION"
+                The line 1 of stdout should eq "Carbs Packaging Tools, version $VERSION"
             End
         End
 
diff --git a/src/cpt-build b/src/cpt-build
index cb93949..4eccbd1 100755
--- a/src/cpt-build
+++ b/src/cpt-build
@@ -2,7 +2,7 @@
 # Build a package
 
 parser_definition() {
-    setup REST help:usage -- "usage: ${0##*/} [pkg...]"
+    setup REST help:usage -- "usage: ${0##*/} [-tfy] [--root ROOT] [pkg...]"
     msg -- '' 'Options:'
     flag CPT_TEST   -t --test export:1 init:@export -- "Run tests (if they exist)"
     global_options
diff --git a/src/cpt-checksum b/src/cpt-checksum
index 5c6de52..488ab87 100755
--- a/src/cpt-checksum
+++ b/src/cpt-checksum
@@ -1,22 +1,32 @@
 #!/bin/sh -ef
 # Generate checksums
 
-if [ -f ./cpt-lib ]; then . ./cpt-lib; else . cpt-lib; fi
+parser_definition() {
+    setup REST help:usage -- "usage: ${0##*/} [-s] [pkg...]"
+    msg         -- '' 'Options:'
+    flag sha -s --    "Generate checksums using the depracated sha256 algorithm"
+    global_options
+}
 
-case "$1" in
-    --help|-h) out "usage: ${0##*/} [pkg...]"; exit 0 ;;
-    --version|-v) version ;;
-    '') set -- "${PWD##*/}"; export CPT_PATH=${PWD%/*}:$CPT_PATH ;;
-esac
+if [ -f ./cpt-lib ]; then . ./cpt-lib; else . cpt-lib; fi
 
+[ "$1" ] || { set -- "${PWD##*/}"; CPT_PATH=${PWD%/*}:$CPT_PATH ;}
 create_cache
 
 for pkg; do pkg_lint    "$pkg" c; done
 for pkg; do pkg_sources "$pkg" c; done
-
 for pkg; do
-    pkg_checksums "$pkg" | {
-        repo_dir=$(pkg_find "$pkg")
+    # Do not generate checksums if the 'sources' file is empty or it doesn't
+    # exist.
+    repo_dir=$(pkg_find "$pkg")
+    [ -s "$repo_dir/sources" ] || {
+        log "$pkg" "No 'sources' file, skipping checksums"
+        continue
+    }
+
+    # $sha is defined by the parser.
+    # shellcheck disable=2154
+    pkg_checksums "$pkg" "${sha:+sh256}" | {
 
         if [ -w "$repo_dir" ]; then
             tee "$repo_dir/checksums"
diff --git a/src/cpt-lib.in b/src/cpt-lib.in
index 7514608..c055331 100644
--- a/src/cpt-lib.in
+++ b/src/cpt-lib.in
@@ -9,7 +9,9 @@
 # Currently maintained by Cem Keylan.
 
 version() {
-    log "Carbs Packaging Tools" @VERSION@
+    out "Carbs Packaging Tools, version @VERSION@" \
+        @LICENSE@
+
     exit 0
 }
 
@@ -154,6 +156,22 @@ _readlinkf() (
     return 1
 )
 
+_get_digest() {
+    # Get digest algorithm from the given file. It looks for a header on the
+    # file declaring the digest algorithm. Currently only BLAKE3 is supported.
+    # If the file does not include a header, the function will assume that it is
+    # using sha256 as a digest algorithm. If the given file doesn't exist it will
+    # return 1.
+    [ -r "$1" ] || return 1
+    read -r chk < "$1"
+    case $chk in
+        %BLAKE3) chk=b3sum ;;
+        %*) die "Unknown digest algorithm: '${chk#\%}'" ;;
+        *) chk=sh256
+    esac
+    out "$chk"
+}
+
 # This is the public domain getoptions shell library. It also forms a usage
 # function.
 # URL: https://github.com/ko1nksm/getoptions (v2.5.0)
@@ -419,6 +437,21 @@ regesc() {
     sed 's|\\|\\\\|g;s|\[|\\[|g;s|\$|\\$|g;s|\.|\\.|g;s|\*|\\*|g;s|\^|\\^|g'
 }
 
+pkg_download() {
+    # $1: URL
+    # $2: Output (Optional)
+    set -- "$1" "${2:-${1##*/}}"
+    case ${dl_prog##*/} in
+        aria2c|axel) set -- -o "$2" "$1"   ;;
+        curl)        set -- -fLo "$2" "$1" ;;
+        wget|wget2)  set -- -O "$2" "$1"   ;;
+    esac
+
+    "$dl_prog" "$@" || {
+        rm -f "$2"
+        return 1
+    }
+}
 
 prompt() {
     # If a CPT_NOPROMPT variable is set, continue.
@@ -688,10 +721,8 @@ pkg_sources() {
             # interrupt, we handle this ourselves.
             trap_set handle-int
 
-            curl "$src" -fLo "${src##*/}" || {
-                rm -f "${src##*/}"
-                die "$1" "Failed to download $src"
-            }
+            # Download the source
+            pkg_download "$src" || die "$1" "Failed to download $src"
 
             # Restore original trap value.
             trap_set cleanup
@@ -968,10 +999,16 @@ pkg_etcsums() (
     # /etc/ directory for use in "smart" handling of these files.
     log "$1" "Generating etcsums"
 
+    # Try to get the digest algorithm from the installed etcsums file. This
+    # makes sure that old packages continue to have the same digest algorithm
+    # and not a bunch of '.new' files are installed. It's not foolproof at all,
+    # but at least it keeps the /etc directory as clean as possible.
+    digest=$(_get_digest "$sys_db/$1/etcsums") || digest=b3sum
 
+    case $digest in b3sum) out "%BLAKE3"; esac > "$pkg_dir/$1/$pkg_db/$1/etcsums"
     find etc -type f | while read -r file; do
-        sh256 "$file"
-    done > "$pkg_dir/$1/$pkg_db/$1/etcsums"
+        "$digest" "$file"
+    done >> "$pkg_dir/$1/$pkg_db/$1/etcsums"
 )
 
 pkg_tar() {
@@ -1192,6 +1229,8 @@ pkg_checksums() {
 
     [ -f "$repo_dir/sources" ] || return 0
 
+    case ${2:-b3sum} in b3sum) out "%BLAKE3"; esac
+
     while read -r src _ || [ "$src" ]; do
 
         # Skip checksums if it's a comment, or a VCS repository.
@@ -1210,9 +1249,9 @@ pkg_checksums() {
             die "$1" "Couldn't find source '$src'"
         fi
 
-        # An easy way to get 'sha256sum' to print with the 'basename'
+        # An easy way to get 'b3sum' to print with the 'basename'
         # of files is to 'cd' to the file's directory beforehand.
-        (cd "$src_path" && sh256 "${src##*/}") ||
+        (cd "$src_path" && "${2:-b3sum}" "${src##*/}") ||
             die "$1" "Failed to generate checksums"
     done < "$repo_dir/sources"
 }
@@ -1220,13 +1259,18 @@ pkg_checksums() {
 pkg_verify() {
     # Verify all package checksums. This is achieved by generating a new set of
     # checksums and then comparing those with the old set.
-    verify_cmd="NR==FNR{a[\$1];next}/^git  .*/{next}!((\$1)in a){exit 1}"
+    vcmd="NR==FNR{a[\$1];next}/^git  .*/{next}!((\$1)in a){exit 1}"
 
     for pkg; do
         repo_dir=$(pkg_find "$pkg")
+
         [ -f "$repo_dir/sources" ] || continue
 
-        pkg_checksums "$pkg" | awk "$verify_cmd" - "$repo_dir/checksums" || {
+        # Determine the type of digest algorithm from the checksums file to do
+        # verification with.
+        digest="$(_get_digest "$repo_dir/checksums")"
+
+        pkg_checksums "$pkg" "$digest" | awk "$vcmd" - "$repo_dir/checksums" || {
         log "$pkg" "Checksum mismatch"
 
         # Instead of dying above, log it to the terminal. Also define a
@@ -1405,10 +1449,12 @@ pkg_etc() {
         mkdir -p "$CPT_ROOT/$dir"
     done
 
+    digest=$(_get_digest "$mak_dir/c") || digest=b3sum
+
     # Handle files in /etc/ based on a 3-way checksum check.
     find etc ! -type d | while read -r file; do
-        { sum_new=$(sh256 "$file")
-          sum_sys=$(cd "$CPT_ROOT/"; sh256 "$file")
+        { sum_new=$("$digest" "$file")
+          sum_sys=$(cd "$CPT_ROOT/"; "$digest" "$file")
           sum_old=$("$grep" "$file$" "$mak_dir/c"); } 2>/dev/null ||:
 
         logv "$pkg_name" "Doing 3-way handshake for $file"
@@ -2117,6 +2163,15 @@ create_cache() {
                command -v llvm-readelf  ||
                command -v eu-readelf)"} || elf_prog=ldd
 
+    # Use one of the following programs to download package sources. Downloads
+    # are made using the `pkg_download()` function.
+    dl_prog=${CPT_DOWNLOADER:="$(
+              command -v curl      ||
+              command -v wget      ||
+              command -v wget2     ||
+              command -v axel      ||
+              command -v aria2c)"} || dl_prog=curl
+
     # Make note of the user's current ID to do root checks later on.
     # This is used enough to warrant a place here.
     uid=$(id -u)
diff --git a/tools/mkdist.sh b/tools/mkdist.sh
index bcf1caf..98f985c 100755
--- a/tools/mkdist.sh
+++ b/tools/mkdist.sh
@@ -27,6 +27,5 @@ done
 
 cp docs/cpt.info "$basedir/docs/cpt.info"
 
-tar cf "$basedir.tar" "$basedir"
-xz -z "$basedir.tar"
+pax -w "$basedir" | xz -zT 0 > "$basedir.tar.xz"
 rm -rf -- "$basedir"
diff --git a/www/index.md b/www/index.md
index 0c55e80..99ad599 100644
--- a/www/index.md
+++ b/www/index.md
@@ -32,7 +32,7 @@ complements the tools that come with it. It has the following features:
 
 <hr>
 
-### Latest Release: 6.0.4 ([2021-05-12](/timeline?c=6.0.4))
+### Latest Release: 6.1.0 ([2021-07-22](/timeline?c=6.1.0))
 
 - [Download](/uvlist?byage=1)
 - [Changelog](/doc/trunk/CHANGELOG.md)