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List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+larch=yhetil.org@gnu.org Sender: "Guix-devel" X-Migadu-Flow: FLOW_IN X-Migadu-Country: US ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1644071864; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to:list-id:list-help: list-unsubscribe:list-subscribe:list-post:dkim-signature; bh=pfbmxST/Y9QOGQt3A2z0EnfANXA41ancWS/BKj5lp2Q=; b=EUF+NhUdx1kbNFce/lBhyew7Wqlcmcx3hcEUWxOWW+5BeqWf0c0/X3xpopBLWwwN8zEunn 0oC/izaF14uM/Pj7/8MwLyFqy8rWsEAVn44y8Vfp7JROlW6REH/OHxahWwEdwExPfzcV01 9zO2BDglhCekF1BmVwUSxXFwb/gNkTHrLLcWhqjkJ/94/kZFpJSkuU1Xb1wfWRVk7VliHz VA/5Xvrtdr8TTcDNFu70jTJMRlhV8yvOGi3mS7yYSGsp87Im0a7lzg6GlLkWnQAciiHCdE q74YwDBLzd1lbP8Y/f8pMKseWRHse7piNPPbuM1gPOToWRhkkJ3uGgePrwJRaQ== ARC-Seal: i=1; s=key1; d=yhetil.org; t=1644071864; a=rsa-sha256; cv=none; b=lKyYh8m0oc2Qo7v5I+iEkoP+rVloalKY9i4nnNHyX1t0DxMzXpIbYmkugiqQTW1lUuDoH2 4s37kxdhGPlhqCOmbk0hiJJ8KUeseARCL8+2pYU/Wb/ZO2U5ftoipXkO+9nDj8ZIP2C6FR F5eHdjridxUUfRZgEGjmVrj45kwIlj+wQ9yfA/Jx7krLU4akUEGCGETxj056h8CNvCRBCr E9P6iiQEqcgzDKTA81OSjAkot018vlx3cMMbO8vPLifRhQwSvByRZa3EjeiAhwI9ha5QfK DEbZfSkntjYNrOLSxH02iqjjrqXOkKXUB3zWCXRUbsBqbYF2vEea1+LEx7kxXA== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=pass header.d=yoctocell.xyz header.s=mail header.b=StFPamo5; dmarc=pass (policy=none) header.from=yoctocell.xyz; spf=pass (aspmx1.migadu.com: domain of "guix-devel-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="guix-devel-bounces+larch=yhetil.org@gnu.org" X-Migadu-Spam-Score: -6.43 Authentication-Results: aspmx1.migadu.com; dkim=pass header.d=yoctocell.xyz header.s=mail header.b=StFPamo5; dmarc=pass (policy=none) header.from=yoctocell.xyz; spf=pass (aspmx1.migadu.com: domain of "guix-devel-bounces+larch=yhetil.org@gnu.org" designates 209.51.188.17 as permitted sender) smtp.mailfrom="guix-devel-bounces+larch=yhetil.org@gnu.org" X-Migadu-Queue-Id: 9559E354FB X-Spam-Score: -6.43 X-Migadu-Scanner: scn1.migadu.com X-TUID: zA5ov6CxqjO4 --=-=-= Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Andrew schrieb am Donnerstag der 23. Dezember 2021 um 16:16 +03: >> Also, is should there be any preference for using alists or list of >> lists or vice versa? > > Now it should be clear that a -configuration record is preferable as a > service value, lists and alists are special cases for auxiliray > services and shouldn't be used in most cases. But what is the preference between a list and an alist? Why does =E2=80=98etc-service-type=E2=80=99 use '((file contents)) and =E2=80=98home-file-service-type=E2=80=99 use '((file . contents)) ? >>> +There is a module @code{gnu service configuration}, which contains >>> +helpers simplifying configuration definition process. Take a look at >>> +@code{gnu services docker} module or grep for >>> +@code{define-configuration} to find usage examples. >>> + >>> +@c Provide some examples, tips, and rationale behind @code{gnu service >>> +@c configuration} module. >> >> Note that I already sent a patch that (at least tries to) document (gnu >> service configuration)[1]. >> >> One thing that is lacking is when to use (guix records) (which isn=E2=80= =99t >> documented yet) vs (gnu service configuration). There should probably >> be one or two paragraphs about that. >> > > Saw it, I'll try to review and comment on it, when I'll get some spare > time. I'll keep this comment for now, and after the section about gnu > service configuration module is merged, we will add links to it and > provide more info and examples on implementing actual configurations. It has already been merged now. :-) >>> +configuration file name, but in kebab-case: bashrc for bashrc, >> >> Not everyone might familiar with what exactly =E2=80=9Ckebab-case=E2=80= =9D means; we >> should probably leave a footnote or something. >> >> =E2=80=9C=E2=80=A6@code{bashrc} for @file{.bashrc}=E2=80=A6=E2=80=9D >> >> It should also mention that preceding dots should be removed as well. >> What should happend with files named =E2=80=98file.ext=E2=80=99? Should= the field be >> named =E2=80=98file-ext=E2=80=99? > > Added a footnote, provided more expressive examples > @code{bashrc} for @file{.bashrc}, > @code{bash-profile} for @file{.bash_profile}, > @code{tmux-conf} for @file{tmux.conf}, etc. I suggested adding a footnote for the meaning of =E2=80=9Ckebab-case=E2=80= =9D. I don=E2=80=99t think these examples should just be in a footnote. Footnotes are usually used for stuff that might be distracting if put in the text; I wouldn=E2=80=99t consider these examples distracting; they are very valuabl= e. >>> +bash-profile for bash_profile, etc. The implementation for such fields >> >> =E2=80=9C=E2=80=A6@code{bash-profile} for @file{.bash_profile}. >> >> Also, many services have an =E2=80=98extra-content=E2=80=99, =E2=80=98ex= tra-config=E2=80=99, or >> =E2=80=98extra-options=E2=80=99 field. In most cases these just take a = string and >> appends it to some configuration file. Should these instead be named >> =E2=80=98sshd_config=E2=80=99, =E2=80=98xserver-conf=E2=80=99, and =E2= =80=98asound-config=E2=80=99, respectively? >> > > I find this pattern purely-established (content vs conf vs options), > unclear (you can never know where this extra content will be inserted > until you take a look at implementation of serialization function) That=E2=80=99s why we have documentation for all the fields. Moreover, if = it wasn=E2=80=99t documented, the order of the contents of the fields of =E2=80=98home-bash-configuration=E2=80=99 aren=E2=80=99t obvious to the use= r either. >>> +There is no any special requirements or >>> +recommendations here, but it's necessary to make it possible to disable >>> +all the effects of such fields to provide a user with an empty >>> +configuration and let them generate it from scratch with only field for >>> +configuration file. >> >> I don=E2=80=99t really understand what is meant by =E2=80=9Clet them gen= erate it from >> scratch with only field for configuration file=E2=80=9D.=20=20 > > The good examples of the bad behavior are alsa and nginx service types, > they always provide some boilerplate with reasonably good default > configuration, but you can't alter it by setting some fields to #f or > some other values. That applies for the Bash service as well; it unconditionally adds stuff to ~/.bash_profile. > For nginx it's only partially true, you actually can use `file` field, > but it will alter the effect of all other fields and will just use the > file as nginx.conf, kinda conforms what I'm asking here, but makes all > other fields useless. > > Added the following explanation to this item: > > --8<---------------cut here---------------start------------->8--- > For example, setting @code{guix-defaults?} to > @code{#f} and @code{aliases} to @code{'()} will give user an ability to > control the content of @file{.bashrc} solely by setting the value of > @code{bashrc} field. > --8<---------------cut here---------------end--------------->8--- > > >> >> It doesn=E2=80=99t mention if a configuration record should cover all the >> configuration options available in a configuration file. For example, >> the current =E2=80=98openssh-configuration=E2=80=99 has quite a few opti= ons, but these >> obviously don=E2=80=99t cover all the options available in /etc/ssh/sshd= _config, >> which is why there is an =E2=80=9Cescape hatch=E2=80=9D, =E2=80=98extra-= content=E2=80=99 field. >> >> In some cases a program might have too many configuration fields for us >> to map using configuration records, e.g., Git. In rde, the approach we >> took was to use nested lists to represent the INI configuration. I >> think this approach could also be mentioned here. >> > > This is mentioned below, as well as the problem of closed-world > assumption. Software should be fully configurable with field for > respective config file, escape hatch should be a part of this field. > > Escape hatch is necessary to allow to reuse already existing > configuration, but not to provide configuration, which can't be > expressed by respective configuration field. But the Git service in rde uses a =E2=80=98config-extra-content=E2=80=99 fi= eld, which is basically the same thing as =E2=80=98extra-content=E2=80=99 or =E2=80=98ext= ra-config=E2=80=99, right? > and uneccesary (we do not need extra-* fields because we can add any > extra content using G-expression inside our primary configuration, see > sway example below). >>> +simple, it requires to write serializer once for one configuration >> ^ =E2=80=9Cone=E2=80=9D or =E2=80=9Cyou=E2=80=9D > > Sounds better for me without one or you. I don=E2=80=99t think it is grammatically correct to not put an object after =E2=80=9Crequires to=E2=80=9D. >>> +configuration and resulting app config, including different field >>> +casing, new semantic units. >> >> But it means that the syntax for configuring a program is more >> Scheme-like. For example, the Dovecot service provides a very >> complicated but Schemeish interface for configuring Dovecot, though as >> you have mentioned, it might be missing some fields since the Dovecot >> configuration file might have changed since the creation of the service. >> > > Yes it is more Scheme-flavored, but it doesn't mean good. I can write a > good rationale on this topic, but will do it next time, now I'll just > give you an example, which should be relevant to you: Imagine writing an > importer (for `guix home import` for example) from XML to SXML, now > imagine that instead of SXML we have Scheme-like configuration. It > hours and days more work. Implementing and maintaining such > Scheme-flavored configuration is a big pain, especially if software > still changes and config options isn't stable yet. Sorry for being unclear, I meant that the docs were very one-sided and only mentioned the advantages, and not the disadvantages. It should, IMO, give a more objective view of problem. >>> +(which also can be used for i3). The following value of @code{config} >>> +field of @code{home-sway-configuration}: >> >> =E2=80=98home-sway-configuration=E2=80=99 isn=E2=80=99t in Guix as of no= w, so it probably >> shouldn=E2=80=99t be mentioned, as least for now. > > Don't think it's a big problem. We can treat it as an imaginary example > for now. Then it should be clearly stated that it currently doesn=E2=80=99t exist in Guix. A few minutes later, Andrew wrote: > * guix.texi (Writing Service Configuration): New section. > --- > doc/guix.texi | 252 +++++++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 248 insertions(+), 4 deletions(-) > > diff --git a/doc/guix.texi b/doc/guix.texi > index 333cb4117a..29d85d3dc5 100644 > --- a/doc/guix.texi > +++ b/doc/guix.texi > @@ -10363,6 +10363,7 @@ compiling modules. It can be @code{#f}, @code{#t= }, or @code{'detailed}. > The other arguments are as for @code{derivation} (@pxref{Derivations}). > @end deffn >=20=20 > +@anchor{file-like objects} > @cindex file-like objects > The @code{local-file}, @code{plain-file}, @code{computed-file}, > @code{program-file}, and @code{scheme-file} procedures below return > @@ -15942,6 +15943,7 @@ symlink: > Return a service that sets the host name to @var{name}. > @end deffn >=20=20 > +@anchor{console-font-service-type} > @defvr {Scheme Variable} console-font-service-type > Install the given fonts on the specified ttys (fonts are per > virtual console on the kernel Linux). The value of this service is a li= st of > @@ -33717,6 +33719,7 @@ a daemon that can execute application bundles (so= metimes referred to as >=20=20 > @end defvr >=20=20 > +@anchor{docker-configuration} > @deftp {Data Type} docker-configuration > This is the data type representing the configuration of Docker and Conta= inerd. >=20=20 > @@ -35652,10 +35655,11 @@ them in an @code{operating-system} declaration.= But how do we define > them in the first place? And what is a service anyway? >=20=20 > @menu > -* Service Composition:: The model for composing services. > -* Service Types and Services:: Types and services. > -* Service Reference:: API reference. > -* Shepherd Services:: A particular type of service. > +* Service Composition:: The model for composing services. > +* Service Types and Services:: Types and services. > +* Writing Service Configurations:: A guideline for writing guix services. > +* Service Reference:: API reference. > +* Shepherd Services:: A particular type of service. > @end menu >=20=20 > @node Service Composition > @@ -35851,6 +35855,245 @@ There can be only one instance of an extensible= service type such as > Still here? The next section provides a reference of the programming > interface for services. >=20=20 > +@node Writing Service Configurations > +@subsection Writing Service Configurations > + > +Guix already contains a wide variety of system and home services, but > +sometimes users might want to add new services. This section contains > +tips for simplifying this process, and should help to make service > +configurations and their implementations more consistent. > + > +@quotation Note > +If you find any exceptions or patterns missing in this section, please > +send a patch with additions/changes to @email{guix-devel@@gnu.org} > +mailing list or just start a discussion/ask a question. > +@end quotation > + > +@subsubheading Configuration Itself > + > +As we know from previous sections, a Guix service can accept a service > +value, usually some kind of configuration record and optionally, be > +extended with additional values by other services (@pxref{Service > +Composition}). > + > +When being extended, most services take some kind of configuration > +record or a list thereof, but in some cases a simpler value is all > +that is necessary. > + > +There are some cases, when the service accepts a list of pairs or some > +other non-record values. For example, @code{console-font-service-type} > +(@pxref{console-font-service-type}) accepts an > +association list, and @code{etc-service-type} (@pxref{etc-service-type}) > +accepts a list of lists. Those services are kinda special, they do > +auxiliary work of setting up some part of the operating system or home > +environment, or just an intermediate helpers used by other Guix > +services. For example @code{etc-service-type} is not that useful on its > +own, but it helps other services to create files in /etc directory, when > +it necessary. ^ missing =E2=80=9Cis=E2=80=9D Use @file{/etc} instead of just /etc. > +However, in most cases a Guix service is wrapping some software, which > +consists of one or more packages, and configuration file or files. > +Therefore, the value for such service is quite complicated and it's hard > +to represent it with just a list or basic data type, in such cases we > +use a record. Each such record (@pxref{SRFI-9 Records, Scheme Records,, > +guile, GNU Guile Reference Manual}) have @samp{-configuration} suffix, s/have/shoudl have a/ > +for example, the @code{docker-service-type} should accept a record type > +named @code{docker-configuration}, which contains fields used to > +configure Docker. Configuration records for home services should also > +have a @code{home-} prefix in their name. > + > +There is a module @code{gnu service configuration}, which contains > +helpers simplifying configuration definition process. Take a look at > +@code{gnu services docker} module or grep for > +@code{define-configuration} to find usage examples. Since the docs for (gnu services configuration) already exists, a link pointing to the node should be used. > +After a configuration record has been properly named and defined let's > +discuss how to name and define the fields, and which approach to use for > +implementing the serialization code related to them. > + > +In this context, the @dfn{serialization} is a process of converting spurious =E2=80=9Cthe=E2=80=9D > +values of the fields defined in service configuration into a string or ^ =E2=80=9Ca=E2=80=9D =20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20= =20=20=20=20=20=20=20=20=20 > +strings of a target config format, which will be put to the s/config/configuration/ > +configuration file or files used by the program. s/the/a/ > +@subsubheading Configuration Record Fields > + > +@enumerate > +@item > +It's a good idea to have one or more fields for specifying the package > +or packages that will be installed by a service. For example, > +@code{docker-configuration} has @code{docker}, @code{docker-cli}, > +@code{containerd} fields (@pxref{docker-configuration}). Sometimes it > +make sense to make a field, which accepts a list of packages for cases, > +where an arbitrary list of plugins can be passed to the configuration. > +There are some services, which provide a field called @code{package} in > +their configuration, which is ok, but the way it done in ^ =E2=80=9Cis=E2=80=9D =20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20= =20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20= =20 > +@code{docker-configuration} is more flexible and thus preferable. Just to make things clear, it would be preferable to call the field =E2=80=98git=E2=80=99 instead of =E2=80=98package=E2=80=99 even if there is= only one packages that will be installed? > +@item > +Fields for configuration files, should be name the same as target > +configuration file name, but in kebab-case@footnote{The case used for > +identifiers in languages of Lisp family, example: > +@code{this-is-kebab-case}.}: @code{bashrc} for @file{.bashrc}, > +@code{bash-profile} for @file{.bash_profile}, > +@code{tmux-conf} for @file{tmux.conf}, etc. The implementation > +for such fields will be discussed in the next subsubsection. > + > +@item > +Other fields in most cases add some boilerplates/reasonable defaults to > +configuration files, enable/disable installation of some packages or > +provide other custom behavior, for example @code{guix-defaults?} or > +@code{aliases} fields in @code{home-bash-configuration} > +(@pxref{home-bash-configuration}). There is no any special requirements > +or recommendations here, but it's necessary to make it possible to > +disable all the effects of such fields to provide a user with an empty > +configuration and let them generate it from scratch with only field for > +configuration file. For example, setting @code{guix-defaults?} to > +@code{#f} and @code{aliases} to @code{'()} will give user an ability to > +control the content of @file{.bashrc} solely by setting the value of > +@code{bashrc} field. > + > + > +@end enumerate > + > +@subsubheading Fields for Configuration Files > + > +The field should accept a data structure (preferably a combination of > +simple lists, alists, @ref{Vectors, vectors,, guile,}, > +@ref{G-Expressions, gexps} and basic data types), which will be > +serialized to target configuration format, in other words, it should ^ =E2=80=9Cthe=E2=80=9D =20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20 > +provide an alternative Lisp syntax, which can be later translated to a > +target one, like SXML to XML. Such approach is quite flexible and > +simple, it requires to write serializer once for one configuration ^ =E2=80=9Cone=E2=80=9D ^ =E2=80=9Ca=E2=80=9D =20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20 > +format and can be reused multiple times in different Guix services. > + > +Let's take a look at JSON: we implement serialization function, which ^ =E2=80=9Ca=E2=80=9D =20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20= =20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20 > +converts vectors to arrays, alists to objects (AKA dictionaries or > +associative arrays), numbers to numbers, gexps to the strings, s/the// > +@ref{file-like objects} (@pxref{G-Expressions}) to the strings, which Likewise > +contains the path to the file in the store, @code{#t} to @code{true} and s/contains/contain/ > +so on, and now we have all programs using JSON as a format for > +configurations covered. Maybe some fine-tunning will be needed for > +particular application, but the primary serialization part is already s/application/programs/ > +finished. > + > +The pros and cons of such approach is inherited from open-world > +assumption. It doesn't matter if the underlying applications provides > +new configuration options, we don't need to change anything in the > +service configuration and its serialization code, it will work perfectly > +fine. On the other hand, it is harder to type check and structure check > +at ``compile-time'', and we can end up with a configuration, which won't > +be accepted by the target program due to unexisting, misspelled or > +wrongly-typed options. It's possible to add those checks, but we will > +get the drawbacks of closed-world assumption: we need to keep the A link or footnote for =E2=80=9Cclosed-world assumption=E2=80=9D should be = provided. > +service implementation in-sync with app config options, and it will make =E2=80=9C=E2=80=A6with the configuration options of the program, and it wil= l make it=E2=80=A6=E2=80=9D > +impossible to use the same service with older/newer package version, s|/|or| s/version/versions/ > +which has a slightly different list of available options and will add an > +excessive maintanence load. > + > +However, for some applications with really stable configuration those > +checks can be helpful and should be implemented if possible, for some > +others we can implement them only partially. > + > +The alternative approach applied in some exitsting services is to use > +records for defining the structure of configuration field, it has the > +same downsides of closed-world assumption and a few more problems: > + > +@enumerate > +@item > +It has to replicate all the available options for the app (sometimes > +hundreds or thousands) to allow the user express any configuration they > +want. > +@item > +Having a few records adds one more layer of abstraction between service > +configuration and resulting app config, including different field s/app/program/ > +casing, new semantic units. > +@c provide examples? > +@item > +It harder to implement optional settings, serialization becomes very ^ =E2=80=9Cis=E2=80=9D > +ad-hoc and hard to reuse among other services with the same target > +config format. > +@end enumerate > + > +Exceptions can exist, but the overall idea is to provide a lispy syntax > +for target configuration. Take a look at Sway example configuration > +(which also can be used for i3). The following value of @code{config} > +field of @code{home-sway-configuration}: > + > +@example > +`((include ,(local-file "./sway/config")) > + (bindsym $mod+Ctrl+Shift+a exec emacsclient -c --eval "'(eshell)'") > + (bindsym $mod+Ctrl+Shift+o "[class=3D\"IceCat\"]" kill) > + (input * ((xkb_layout us,ru) > + (xkb_variant dvorak,)))) > +@end example > + > +would yield something like: > + > +@example > +include /gnu/store/408jwvh6wxxn1j85lj95fniih05gx5xj-config > +bindsym $mod+Ctrl+Shift+a exec emacsclient -c --eval '(eshell)' > +bindsym $mod+Ctrl+Shift+o [class=3D"IceCat"] kill > +input * @{ > + xkb_layout us,ru > + xkb_variant dvorak, > +@} > +@end example > + > +The mapping between Scheme code and resulting configuration is quite > +obvious. The serialization code with some type and structure checks > +takes less than 70 lines and every possible Sway/i3 configuration can be > +expressed using this field. > + > +@subsubheading Let User Escape ^ =E2=80=9CThe=E2=80=9D =20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20=20 > +Sometimes a user already has a configuration file for an program, make s/an/a/ > +sure that it is possible to reuse it directly without rewriting. In the > +example above, the following snippet allows one to include already an > +existing config to the newly generated one utilizing @code{include} > +directive of i3/Sway config language: > + > +@lisp > +(include ,(local-file "./sway/config")) > +@end lisp > + > +When building a resulting config the file-like objects are substituted > +with a path of the file in the store and Sway's @code{include} loads > +this file during startup. The way file-like objects are treated here > +also allows one to specify paths to plugins or other binary files like: > + > +@lisp > +(load-plugin ,(file-append plugin-package "/share/plugin.so")) > +@end lisp > + > +(the example value for imaginary service configuration config file > +field). > + > +In some cases the target configuration language may not have such an > +@code{include} directive and can't provide such a functionallity, to > +workaround it we can do the following trick: > + > +@lisp > +#~(call-with-input-file > + #$(local-file "./sway/config") > + (@@ (ice-9 textual-ports) get-string-all)) > +@end lisp > + > +The =E2=80=98get-string-all=E2=80=99 procedure will read the contents of= the @code{get-string-all} > +@file{./sway/config} file (to be more preciese the copy of this file > +placed in the store), and return a string containing the contents. Once > +serialized, the G-expression will thus be turn into the contents of the > +Sway configuration file in @file{./sway/config}. This code can be > +easily combined with the rest of Sway's configuration, additionally, we > +can control the place where the content of @file{./sway/config} will > +appear in resulting file by moving this snippet around. > + > +Following these simple rules will help to make simple, consistent and > +maintainable service configurations, and will let users express any > +possible needs and reuse existing configuration files. > + > @node Service Reference > @subsection Service Reference >=20=20 > @@ -36076,6 +36319,7 @@ The type of the ``boot service'', which produces = the @dfn{boot script}. > The boot script is what the initial RAM disk runs when booting. > @end defvr >=20=20 > +@anchor{etc-service-type} > @defvr {Scheme Variable} etc-service-type > The type of the @file{/etc} service. This service is used to create > files under @file{/etc} and can be extended by > --=20 > 2.34.0 Another point that might be worth bringing up is what we should do with existing services which do not adhere to these guidelines. Should we re-write them or just keep them as-is? Sorry for the long delay! 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