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diff --git a/doc/guix.texi b/doc/guix.texi
index 1fd2e21608..7dde9b727b 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -7975,6 +7975,10 @@ The exact set of supported keywords depends on the build system
@code{#:phases}. The @code{#:phases} keyword in particular lets you
modify the set of build phases for your package (@pxref{Build Phases}).
+The REPL has dedicated commands to interactively inspect values of some
+of these arguments, as a convenient debugging aid (@pxref{Using Guix
+Interactively}).
+
@quotation Compatibility Note
Until version 1.3.0, the @code{arguments} field would typically use
@code{quote} (@code{'}) or @code{quasiquote} (@code{`}) and no
@@ -8774,6 +8778,23 @@ when @var{cut?} returns true for a given package. When @var{deep?} is true, @va
applied to implicit inputs as well.
@end deffn
+@quotation Tips
+Understanding what a variant really looks like can be difficult as one
+starts combining the tools shown above. There are several ways to
+inspect a package before attempting to build it that can prove handy:
+
+@itemize
+@item
+You can inspect the package interactively at the REPL, for instance to
+view its inputs, the code of its build phases, or its configure flags
+(@pxref{Using Guix Interactively}).
+
+@item
+When rewriting dependencies, @command{guix graph} can often help
+visualize the changes that are made (@pxref{Invoking guix graph}).
+@end itemize
+@end quotation
+
@node Writing Manifests
@section Writing Manifests
@@ -10585,6 +10606,11 @@ we have seen before. @xref{Build Utilities}, for more about
the helpers used by this phase, and for more examples of
@code{modify-phases}.
+@quotation Tip
+You can inspect the code associated with a package's @code{#:phases}
+argument interactively, at the REPL (@pxref{Using Guix Interactively}).
+@end quotation
+
@cindex code staging
@cindex staging, of code
Keep in mind that build phases are code evaluated at the time the
@@ -12763,6 +12789,30 @@ scheme@@(guix-user)> (scandir (string-append $3 "/bin"))
$5 = ("." ".." "egrep" "fgrep" "grep")
@end example
+As a packager, you may be willing to inspect the build phases or flags
+of a given package; this is particularly useful when relying a lot on
+inheritance to define package variants (@pxref{Defining Package
+Variants}) or when package arguments are a result of some computation,
+both of which can make it harder to foresee what ends up in the package
+arguments. Additional commands let you inspect those package arguments:
+
+@example
+scheme@@(guix-user)> ,phases grep
+$1 = (modify-phases %standard-phases
+ (add-after 'install 'fix-egrep-and-fgrep
+ (lambda* (#:key outputs #:allow-other-keys)
+ (let* ((out (assoc-ref outputs "out"))
+ (bin (string-append out "/bin")))
+ (substitute* (list (string-append bin "/egrep")
+ (string-append bin "/fgrep"))
+ (("^exec grep")
+ (string-append "exec " bin "/grep")))))))
+scheme@@(guix-user)> ,configure-flags findutils
+$2 = (list "--localstatedir=/var")
+scheme@@(guix-user)> ,make-flags binutils
+$3 = '("MAKEINFO=true")
+@end example
+
At a lower-level, a useful command is @code{lower}: it takes a file-like
object and ``lowers'' it into a derivation (@pxref{Derivations}) or a
store file:
@@ -12794,6 +12844,17 @@ This is similar to the @option{--verbosity} command-line option
shows build events only, and higher levels print build logs.
@end deffn
+@deffn {REPL command} phases @var{package}
+@deffnx {REPL command} configure-flags @var{package}
+@deffnx {REPL command} make-flags @var{package}
+These REPL commands return the value of one element of the
+@code{arguments} field of @var{package} (@pxref{package Reference}): the
+first one show the staged code associated with @code{#:phases}
+(@pxref{Build Phases}), the second shows the code for
+@code{#:configure-flags}, and @code{,make-flags} returns the code for
+@code{#:make-flags}.
+@end deffn
+
@deffn {REPL command} run-in-store @var{exp}
Run @var{exp}, a monadic expression, through the store monad.
@xref{The Store Monad}, for more information.