Rename doc/manual{src -> source}

This is needed to avoid this
https://github.com/mesonbuild/meson/issues/13774 when we go back to
making our subproject directory `src`.

doc/manual/source/installation/prerequisites-source.md

@@ -0,0 +1,80 @@
+# Prerequisites
+
+  - GNU Autoconf (<https://www.gnu.org/software/autoconf/>) and the
+    autoconf-archive macro collection
+    (<https://www.gnu.org/software/autoconf-archive/>). These are
+    needed to run the bootstrap script.
+
+  - GNU Make.
+
+  - Bash Shell. The `./configure` script relies on bashisms, so Bash is
+    required.
+
+  - A version of GCC or Clang that supports C++20.
+
+  - `pkg-config` to locate dependencies. If your distribution does not
+    provide it, you can get it from
+    <http://www.freedesktop.org/wiki/Software/pkg-config>.
+
+  - The OpenSSL library to calculate cryptographic hashes. If your
+    distribution does not provide it, you can get it from
+    <https://www.openssl.org>.
+
+  - The `libbrotlienc` and `libbrotlidec` libraries to provide
+    implementation of the Brotli compression algorithm. They are
+    available for download from the official repository
+    <https://github.com/google/brotli>.
+
+  - cURL and its library. If your distribution does not provide it, you
+    can get it from <https://curl.haxx.se/>.
+
+  - The SQLite embedded database library, version 3.6.19 or higher. If
+    your distribution does not provide it, please install it from
+    <http://www.sqlite.org/>.
+
+  - The [Boehm garbage collector (`bdw-gc`)](http://www.hboehm.info/gc/) to reduce
+    the evaluator’s memory consumption (optional).
+
+    To enable it, install
+    `pkgconfig` and the Boehm garbage collector, and pass the flag
+    `--enable-gc` to `configure`.
+
+  - The `boost` library of version 1.66.0 or higher. It can be obtained
+    from the official web site <https://www.boost.org/>.
+
+  - The `editline` library of version 1.14.0 or higher. It can be
+    obtained from the its repository
+    <https://github.com/troglobit/editline>.
+
+  - The `libsodium` library for verifying cryptographic signatures
+    of contents fetched from binary caches.
+    It can be obtained from the official web site
+    <https://libsodium.org>.
+
+  - Recent versions of Bison and Flex to build the parser. (This is
+    because Nix needs GLR support in Bison and reentrancy support in
+    Flex.) For Bison, you need version 2.6, which can be obtained from
+    the [GNU FTP server](ftp://alpha.gnu.org/pub/gnu/bison). For Flex,
+    you need version 2.5.35, which is available on
+    [SourceForge](http://lex.sourceforge.net/). Slightly older versions
+    may also work, but ancient versions like the ubiquitous 2.5.4a
+    won't.
+
+  - The `libseccomp` is used to provide syscall filtering on Linux. This
+    is an optional dependency and can be disabled passing a
+    `--disable-seccomp-sandboxing` option to the `configure` script (Not
+    recommended unless your system doesn't support `libseccomp`). To get
+    the library, visit <https://github.com/seccomp/libseccomp>.
+
+  - On 64-bit x86 machines only, `libcpuid` library
+    is used to determine which microarchitecture levels are supported
+    (e.g., as whether to have `x86_64-v2-linux` among additional system types).
+    The library is available from its homepage
+    <http://libcpuid.sourceforge.net>.
+    This is an optional dependency and can be disabled
+    by providing a `--disable-cpuid` to the `configure` script.
+
+  - Unless `./configure --disable-unit-tests` is specified, GoogleTest (GTest) and
+    RapidCheck are required, which are available at
+    <https://google.github.io/googletest/> and
+    <https://github.com/emil-e/rapidcheck> respectively.