diff --git a/sql/swh-schema.sql b/sql/swh-schema.sql
index b4d33e66..4fbbcef1 100644
--- a/sql/swh-schema.sql
+++ b/sql/swh-schema.sql
@@ -1,623 +1,1034 @@
 ---
 --- Software Heritage Data Model
 ---
 
 -- drop schema if exists swh cascade;
 -- create schema swh;
 -- set search_path to swh;
 
 create table dbversion
 (
   version     int primary key,
   release     timestamptz,
   description text
 );
 
 insert into dbversion(version, release, description)
       values(87, now(), 'Work In Progress');
 
 -- a SHA1 checksum (not necessarily originating from Git)
 create domain sha1 as bytea check (length(value) = 20);
 
 -- a Git object ID, i.e., a SHA1 checksum
 create domain sha1_git as bytea check (length(value) = 20);
 
 -- a SHA256 checksum
 create domain sha256 as bytea check (length(value) = 32);
 
 -- UNIX path (absolute, relative, individual path component, etc.)
 create domain unix_path as bytea;
 
 -- a set of UNIX-like access permissions, as manipulated by, e.g., chmod
 create domain file_perms as int;
 
 create type content_status as enum ('absent', 'visible', 'hidden');
 
 -- Checksums about actual file content. Note that the content itself is not
 -- stored in the DB, but on external (key-value) storage. A single checksum is
 -- used as key there, but the other can be used to verify that we do not inject
 -- content collisions not knowingly.
 create table content
 (
   sha1      sha1 primary key,
   sha1_git  sha1_git not null,
   sha256    sha256 not null,
   length    bigint not null,
   ctime     timestamptz not null default now(),
             -- creation time, i.e. time of (first) injection into the storage
   status    content_status not null default 'visible',
   object_id bigserial
 );
 
 create unique index on content(sha1_git);
 create unique index on content(sha256);
 create index on content(ctime);  -- TODO use a BRIN index here (postgres >= 9.5)
 create index on content(object_id);
 
 -- Asynchronous notification of new content insertions
 create function notify_new_content()
   returns trigger
   language plpgsql
 as $$
   begin
     perform pg_notify('new_content', encode(new.sha1, 'hex'));
     return null;
   end;
 $$;
 
 create trigger notify_new_content
   after insert on content
   for each row
   execute procedure notify_new_content();
 
 
 -- Entities constitute a typed hierarchy of organization, hosting
 -- facilities, groups, people and software projects.
 --
 -- Examples of entities: Software Heritage, Debian, GNU, GitHub,
 -- Apache, The Linux Foundation, the Debian Python Modules Team, the
 -- torvalds GitHub user, the torvalds/linux GitHub project.
 --
 -- The data model is hierarchical (via the parent attribute) and might
 -- store sub-branches of existing entities. The key feature of an
 -- entity is might be *listed* (if it is available in listable_entity)
 -- to retrieve information about its content, i.e: sub-entities,
 -- projects, origins.
 
 -- Types of entities.
 --
 -- - organization: a root entity, usually backed by a non-profit, a
 -- company, or another kind of "association". (examples: Software
 -- Heritage, Debian, GNU, GitHub)
 --
 -- - group_of_entities: used for hierarchies, doesn't need to have a
 -- concrete existence. (examples: GNU hosting facilities, Debian
 -- hosting facilities, GitHub users, ...)
 --
 -- - hosting: a hosting facility, can usually be listed to generate
 -- other data. (examples: GitHub git hosting, alioth.debian.org,
 -- snapshot.debian.org)
 --
 -- - group_of_persons: an entity representing a group of
 -- persons. (examples: a GitHub organization, a Debian team)
 --
 -- - person: an entity representing a person. (examples:
 -- a GitHub user, a Debian developer)
 --
 -- - project: an entity representing a software project. (examples: a
 -- GitHub project, Apache httpd, a Debian source package, ...)
 create type entity_type as enum (
   'organization',
   'group_of_entities',
   'hosting',
   'group_of_persons',
   'person',
   'project'
 );
 
 -- The history of entities. Allows us to keep historical metadata
 -- about entities.  The temporal invariant is the uuid. Root
 -- organization uuids are manually generated (and available in
 -- swh-data.sql).
 --
 -- For generated entities (generated = true), we can provide
 -- generation_metadata to allow listers to retrieve the uuids of previous
 -- iterations of the entity.
 --
 -- Inactive entities that have been active in the past (active =
 -- false) should register the timestamp at which we saw them
 -- deactivate, in a new entry of entity_history.
 create table entity_history
 (
   id               bigserial primary key,
   uuid             uuid,
   parent           uuid,             -- should reference entity_history(uuid)
   name             text not null,
   type             entity_type not null,
   description      text,
   homepage         text,
   active           boolean not null, -- whether the entity was seen on the last listing
   generated        boolean not null, -- whether this entity has been generated by a lister
   lister_metadata  jsonb,            -- lister-specific metadata, used for queries
   metadata         jsonb,
   validity         timestamptz[]     -- timestamps at which we have seen this entity
 );
 
 create index on entity_history(uuid);
 create index on entity_history(name);
 
 -- The entity table provides a view of the latest information on a
 -- given entity. It is updated via a trigger on entity_history.
 create table entity
 (
   uuid             uuid primary key,
   parent           uuid references entity(uuid) deferrable initially deferred,
   name             text not null,
   type             entity_type not null,
   description      text,
   homepage         text,
   active           boolean not null, -- whether the entity was seen on the last listing
   generated        boolean not null, -- whether this entity has been generated by a lister
   lister_metadata  jsonb,            -- lister-specific metadata, used for queries
   metadata         jsonb,
   last_seen        timestamptz,      -- last listing time or disappearance time for active=false
   last_id          bigint references entity_history(id) -- last listing id
 );
 
 create index on entity(name);
 create index on entity using gin(lister_metadata jsonb_path_ops);
 
 -- Register the equivalence between two entities. Allows sideways
 -- navigation in the entity table
 create table entity_equivalence
 (
   entity1 uuid references entity(uuid),
   entity2 uuid references entity(uuid),
   primary key (entity1, entity2),
   constraint order_entities check (entity1 < entity2)
 );
 
 -- Register a lister for a specific entity.
 create table listable_entity
 (
   uuid         uuid references entity(uuid) primary key,
   enabled      boolean not null default true, -- do we list this entity automatically?
   list_engine  text,  -- crawler to be used to list entity's content
   list_url     text,  -- root URL to start the listing
   list_params  jsonb,  -- org-specific listing parameter
   latest_list  timestamptz  -- last time the entity's content has been listed
 );
 
 -- Log of all entity listings (i.e., entity crawling) that have been
 -- done in the past, or are still ongoing.
 create table list_history
 (
   id        bigserial primary key,
   entity    uuid references listable_entity(uuid),
   date      timestamptz not null,
   status    boolean,  -- true if and only if the listing has been successful
   result    jsonb,     -- more detailed return value, depending on status
   stdout    text,
   stderr    text,
   duration  interval  -- fetch duration of NULL if still ongoing
 );
 
 
 -- An origin is a place, identified by an URL, where software can be found. We
 -- support different kinds of origins, e.g., git and other VCS repositories,
 -- web pages that list tarballs URLs (e.g., http://www.kernel.org), indirect
 -- tarball URLs (e.g., http://www.example.org/latest.tar.gz), etc. The key
 -- feature of an origin is that it can be *fetched* (wget, git clone, svn
 -- checkout, etc.) to retrieve all the contained software.
 create table origin
 (
   id       bigserial primary key,
   type     text, -- TODO use an enum here (?)
   url      text not null,
   lister   uuid references listable_entity(uuid),
   project  uuid references entity(uuid)
 );
 
 create index on origin(type, url);
 
 -- Asynchronous notification of new origin insertions
 create function notify_new_origin()
   returns trigger
   language plpgsql
 as $$
   begin
     perform pg_notify('new_origin', new.id::text);
     return null;
   end;
 $$;
 
 create trigger notify_new_origin
   after insert on origin
   for each row
   execute procedure notify_new_origin();
 
 -- Content we have seen but skipped for some reason. This table is
 -- separate from the content table as we might not have the sha1
 -- checksum of that data (for instance when we inject git
 -- repositories, objects that are too big will be skipped here, and we
 -- will only know their sha1_git). 'reason' contains the reason the
 -- content was skipped. origin is a nullable column allowing to find
 -- out which origin contains that skipped content.
 create table skipped_content
 (
   sha1      sha1,
   sha1_git  sha1_git,
   sha256    sha256,
   length    bigint not null,
   ctime     timestamptz not null default now(),
   status    content_status not null default 'absent',
   reason    text not null,
   origin    bigint references origin(id),
   object_id bigserial,
   unique (sha1, sha1_git, sha256)
 );
 
 -- Those indexes support multiple NULL values.
 create unique index on skipped_content(sha1);
 create unique index on skipped_content(sha1_git);
 create unique index on skipped_content(sha256);
 create index on skipped_content(object_id);
 
 -- Asynchronous notification of new skipped content insertions
 create function notify_new_skipped_content()
   returns trigger
   language plpgsql
 as $$
   begin
   perform pg_notify('new_skipped_content', json_build_object(
       'sha1', encode(new.sha1, 'hex'),
       'sha1_git', encode(new.sha1_git, 'hex'),
       'sha256', encode(new.sha256, 'hex')
     )::text);
     return null;
   end;
 $$;
 
 create trigger notify_new_skipped_content
   after insert on skipped_content
   for each row
   execute procedure notify_new_skipped_content();
 
 
 -- Log of all origin fetches (i.e., origin crawling) that have been done in the
 -- past, or are still ongoing. Similar to list_history, but for origins.
 create table fetch_history
 (
   id        bigserial primary key,
   origin    bigint references origin(id),
   date      timestamptz not null,
   status    boolean,  -- true if and only if the fetch has been successful
   result    jsonb,     -- more detailed returned values, times, etc...
   stdout    text,
   stderr    text,     -- null when status is true, filled otherwise
   duration  interval  -- fetch duration of NULL if still ongoing
 );
 
 
 -- A file-system directory.  A directory is a list of directory entries (see
 -- tables: directory_entry_{dir,file}).
 --
 -- To list the contents of a directory:
 -- 1. list the contained directory_entry_dir using array dir_entries
 -- 2. list the contained directory_entry_file using array file_entries
 -- 3. list the contained directory_entry_rev using array rev_entries
 -- 4. UNION
 --
 -- Synonyms/mappings:
 -- * git: tree
 create table directory
 (
   id            sha1_git primary key,
   dir_entries   bigint[],  -- sub-directories, reference directory_entry_dir
   file_entries  bigint[],  -- contained files, reference directory_entry_file
   rev_entries   bigint[],  -- mounted revisions, reference directory_entry_rev
   object_id     bigserial  -- short object identifier
 );
 
 create index on directory using gin (dir_entries);
 create index on directory using gin (file_entries);
 create index on directory using gin (rev_entries);
 create index on directory(object_id);
 
 -- Asynchronous notification of new directory insertions
 create function notify_new_directory()
   returns trigger
   language plpgsql
 as $$
   begin
     perform pg_notify('new_directory', encode(new.id, 'hex'));
     return null;
   end;
 $$;
 
 create trigger notify_new_directory
   after insert on directory
   for each row
   execute procedure notify_new_directory();
 
 
 -- A directory entry pointing to a sub-directory.
 create table directory_entry_dir
 (
   id      bigserial primary key,
   target  sha1_git,   -- id of target directory
   name    unix_path,  -- path name, relative to containing dir
   perms   file_perms  -- unix-like permissions
 );
 
 create unique index on directory_entry_dir(target, name, perms);
 
 -- A directory entry pointing to a file.
 create table directory_entry_file
 (
   id      bigserial primary key,
   target  sha1_git,   -- id of target file
   name    unix_path,  -- path name, relative to containing dir
   perms   file_perms  -- unix-like permissions
 );
 
 create unique index on directory_entry_file(target, name, perms);
 
 -- A directory entry pointing to a revision.
 create table directory_entry_rev
 (
   id      bigserial primary key,
   target  sha1_git,   -- id of target revision
   name    unix_path,  -- path name, relative to containing dir
   perms   file_perms  -- unix-like permissions
 );
 
 create unique index on directory_entry_rev(target, name, perms);
 
 create table person
 (
   id        bigserial primary key,
   fullname  bytea not null, -- freeform specification; what is actually used in the checksums
                             --     will usually be of the form 'name <email>'
   name      bytea,          -- advisory: not null if we managed to parse a name
   email     bytea           -- advisory: not null if we managed to parse an email
 );
 
 create unique index on person(fullname);
 create index on person(name);
 create index on person(email);
 
 create type revision_type as enum ('git', 'tar', 'dsc', 'svn');
 
 -- the data object types stored in our data model
 create type object_type as enum ('content', 'directory', 'revision', 'release');
 
 -- A snapshot of a software project at a specific point in time.
 --
 -- Synonyms/mappings:
 -- * git / subversion / etc: commit
 -- * tarball: a specific tarball
 --
 -- Revisions are organized as DAGs. Each revision points to 0, 1, or more (in
 -- case of merges) parent revisions. Each revision points to a directory, i.e.,
 -- a file-system tree containing files and directories.
 create table revision
 (
   id                    sha1_git primary key,
   date                  timestamptz,
   date_offset           smallint,
   date_neg_utc_offset   boolean,
   committer_date        timestamptz,
   committer_date_offset smallint,
   committer_date_neg_utc_offset boolean,
   type                  revision_type not null,
   directory             sha1_git,  -- file-system tree
   message               bytea,
   author                bigint references person(id),
   committer             bigint references person(id),
   metadata              jsonb, -- extra metadata (tarball checksums, extra commit information, etc...)
   synthetic             boolean not null default false,  -- true if synthetic (cf. swh-loader-tar)
   object_id             bigserial
 );
 
 create index on revision(directory);
 create index on revision(object_id);
 
 -- Asynchronous notification of new revision insertions
 create function notify_new_revision()
   returns trigger
   language plpgsql
 as $$
   begin
     perform pg_notify('new_revision', encode(new.id, 'hex'));
     return null;
   end;
 $$;
 
 create trigger notify_new_revision
   after insert on revision
   for each row
   execute procedure notify_new_revision();
 
 
 -- either this table or the sha1_git[] column on the revision table
 create table revision_history
 (
   id           sha1_git references revision(id),
   parent_id    sha1_git,
   parent_rank  int not null default 0,
     -- parent position in merge commits, 0-based
   primary key (id, parent_rank)
 );
 
 create index on revision_history(parent_id);
 
 create type origin_visit_status as enum (
   'ongoing',
   'full',
   'partial'
 );
 
 comment on type origin_visit_status IS 'Possible visit status';
 
 -- The timestamps at which Software Heritage has made a visit of the given origin.
 create table origin_visit
 (
   origin    bigint not null references origin(id),
   visit     bigint not null,
   date      timestamptz not null,
   status    origin_visit_status not null,
   metadata  jsonb,
   primary key (origin, visit)
 );
 
 comment on column origin_visit.origin is 'Visited origin';
 comment on column origin_visit.visit is 'Visit number the visit occurred for that origin';
 comment on column origin_visit.date is 'Visit date for that origin';
 comment on column origin_visit.status is 'Visit status for that origin';
 comment on column origin_visit.metadata is 'Metadata associated with the visit';
 
 create index on origin_visit(date);
 
 -- Asynchronous notification of new origin visits
 create function notify_new_origin_visit()
   returns trigger
   language plpgsql
 as $$
   begin
     perform pg_notify('new_origin_visit', json_build_object(
       'origin', new.origin,
       'visit', new.visit
     )::text);
     return null;
   end;
 $$;
 
 create trigger notify_new_origin_visit
   after insert on origin_visit
   for each row
   execute procedure notify_new_origin_visit();
 
 
 -- The content of software origins is indexed starting from top-level pointers
 -- called "branches". Every time we fetch some origin we store in this table
 -- where the branches pointed to at fetch time.
 --
 -- Synonyms/mappings:
 -- * git: ref (in the "git update-ref" sense)
 create table occurrence_history
 (
   origin       bigint references origin(id) not null,
   branch       bytea not null,        -- e.g., b"master" (for VCS), or b"sid" (for Debian)
   target       sha1_git not null,     -- ref target, e.g., commit id
   target_type  object_type not null,  -- ref target type
   object_id    bigserial not null,    -- short object identifier
   visits       bigint[] not null,     -- the visits where that occurrence was valid. References
                                       -- origin_visit(visit), where o_h.origin = origin_visit.origin.
   primary key (object_id)
 );
 
 create index on occurrence_history(target, target_type);
 create index on occurrence_history(origin, branch);
 create unique index on occurrence_history(origin, branch, target, target_type);
 create index on occurrence_history(object_id);
 
 -- Materialized view of occurrence_history, storing the *current* value of each
 -- branch, as last seen by SWH.
 create table occurrence
 (
   origin    bigint references origin(id) not null,
   branch    bytea not null,
   target    sha1_git not null,
   target_type object_type not null,
   primary key(origin, branch)
 );
 
 -- A "memorable" point in the development history of a project.
 --
 -- Synonyms/mappings:
 -- * git: tag (of the annotated kind, otherwise they are just references)
 -- * tarball: the release version number
 create table release
 (
   id          sha1_git primary key,
   target      sha1_git,
   target_type object_type,
   date        timestamptz,
   date_offset smallint,
   date_neg_utc_offset  boolean,
   name        bytea,
   comment     bytea,
   author      bigint references person(id),
   synthetic   boolean not null default false,  -- true if synthetic (cf. swh-loader-tar)
   object_id   bigserial
 );
 
 create index on release(target, target_type);
 create index on release(object_id);
 
 -- Asynchronous notification of new release insertions
 create function notify_new_release()
   returns trigger
   language plpgsql
 as $$
   begin
     perform pg_notify('new_release', encode(new.id, 'hex'));
     return null;
   end;
 $$;
 
 create trigger notify_new_release
   after insert on release
   for each row
   execute procedure notify_new_release();
 
 
 -- Content provenance information caches
 -- https://forge.softwareheritage.org/T547
 --
 -- Those tables aren't expected to be exhaustive, and get filled on a case by
 -- case basis: absence of data doesn't mean the data is not there
 
 -- content <-> revision mapping cache
 --
 -- semantics: "we have seen the content with given id in the given path inside
 -- the given revision"
 
 create table cache_content_revision (
     content         sha1_git not null primary key references content(sha1_git),
     blacklisted     boolean default false,
     revision_paths  bytea[][]
 );
 
 create table cache_content_revision_processed (
     revision  sha1_git not null primary key references revision(id)
 );
 
 -- revision <-> origin_visit mapping cache
 --
 -- semantics: "we have seen the given revision in the given origin during the
 -- given visit"
 
 create table cache_revision_origin (
    revision  sha1_git not null references revision(id),
    origin    bigint not null,
    visit     bigint not null,
    primary key (revision, origin, visit),
    foreign key (origin, visit) references origin_visit (origin, visit)
 );
 
 create index on cache_revision_origin(revision);
 
 -- Computing metadata on sha1's contents
 
 -- Properties (mimetype, encoding, etc...)
 create table content_mimetype (
   id sha1 primary key references content(sha1) not null,
   mimetype bytea not null,
   encoding bytea not null
 );
 
 comment on table content_mimetype is 'Metadata associated to a raw content';
 comment on column content_mimetype.mimetype is 'Raw content Mimetype';
 comment on column content_mimetype.encoding is 'Raw content encoding';
+
+create type languages as enum (
+  'abap',
+  'abnf',
+  'actionscript',
+  'actionscript-3',
+  'ada',
+  'adl',
+  'agda',
+  'alloy',
+  'ambienttalk',
+  'antlr',
+  'antlr-with-actionscript-target',
+  'antlr-with-c#-target',
+  'antlr-with-cpp-target',
+  'antlr-with-java-target',
+  'antlr-with-objectivec-target',
+  'antlr-with-perl-target',
+  'antlr-with-python-target',
+  'antlr-with-ruby-target',
+  'apacheconf',
+  'apl',
+  'applescript',
+  'arduino',
+  'aspectj',
+  'aspx-cs',
+  'aspx-vb',
+  'asymptote',
+  'autohotkey',
+  'autoit',
+  'awk',
+  'base-makefile',
+  'bash',
+  'bash-session',
+  'batchfile',
+  'bbcode',
+  'bc',
+  'befunge',
+  'blitzbasic',
+  'blitzmax',
+  'bnf',
+  'boo',
+  'boogie',
+  'brainfuck',
+  'bro',
+  'bugs',
+  'c',
+  'c#',
+  'c++',
+  'c-objdump',
+  'ca65-assembler',
+  'cadl',
+  'camkes',
+  'cbm-basic-v2',
+  'ceylon',
+  'cfengine3',
+  'cfstatement',
+  'chaiscript',
+  'chapel',
+  'cheetah',
+  'cirru',
+  'clay',
+  'clojure',
+  'clojurescript',
+  'cmake',
+  'cobol',
+  'cobolfree',
+  'coffeescript',
+  'coldfusion-cfc',
+  'coldfusion-html',
+  'common-lisp',
+  'component-pascal',
+  'coq',
+  'cpp-objdump',
+  'cpsa',
+  'crmsh',
+  'croc',
+  'cryptol',
+  'csound-document',
+  'csound-orchestra',
+  'csound-score',
+  'css',
+  'css+django/jinja',
+  'css+genshi-text',
+  'css+lasso',
+  'css+mako',
+  'css+mozpreproc',
+  'css+myghty',
+  'css+php',
+  'css+ruby',
+  'css+smarty',
+  'cuda',
+  'cypher',
+  'cython',
+  'd',
+  'd-objdump',
+  'darcs-patch',
+  'dart',
+  'debian-control-file',
+  'debian-sourcelist',
+  'delphi',
+  'dg',
+  'diff',
+  'django/jinja',
+  'docker',
+  'dtd',
+  'duel',
+  'dylan',
+  'dylan-session',
+  'dylanlid',
+  'earl-grey',
+  'easytrieve',
+  'ebnf',
+  'ec',
+  'ecl',
+  'eiffel',
+  'elixir',
+  'elixir-iex-session',
+  'elm',
+  'emacslisp',
+  'embedded-ragel',
+  'erb',
+  'erlang',
+  'erlang-erl-session',
+  'evoque',
+  'ezhil',
+  'factor',
+  'fancy',
+  'fantom',
+  'felix',
+  'fish',
+  'fortran',
+  'fortranfixed',
+  'foxpro',
+  'fsharp',
+  'gap',
+  'gas',
+  'genshi',
+  'genshi-text',
+  'gettext-catalog',
+  'gherkin',
+  'glsl',
+  'gnuplot',
+  'go',
+  'golo',
+  'gooddata-cl',
+  'gosu',
+  'gosu-template',
+  'groff',
+  'groovy',
+  'haml',
+  'handlebars',
+  'haskell',
+  'haxe',
+  'hexdump',
+  'html',
+  'html+cheetah',
+  'html+django/jinja',
+  'html+evoque',
+  'html+genshi',
+  'html+handlebars',
+  'html+lasso',
+  'html+mako',
+  'html+myghty',
+  'html+php',
+  'html+smarty',
+  'html+twig',
+  'html+velocity',
+  'http',
+  'hxml',
+  'hy',
+  'hybris',
+  'idl',
+  'idris',
+  'igor',
+  'inform-6',
+  'inform-6-template',
+  'inform-7',
+  'ini',
+  'io',
+  'ioke',
+  'irc-logs',
+  'isabelle',
+  'j',
+  'jade',
+  'jags',
+  'jasmin',
+  'java',
+  'java-server-page',
+  'javascript',
+  'javascript+cheetah',
+  'javascript+django/jinja',
+  'javascript+genshi-text',
+  'javascript+lasso',
+  'javascript+mako',
+  'javascript+mozpreproc',
+  'javascript+myghty',
+  'javascript+php',
+  'javascript+ruby',
+  'javascript+smarty',
+  'jcl',
+  'json',
+  'json-ld',
+  'julia',
+  'julia-console',
+  'kal',
+  'kconfig',
+  'koka',
+  'kotlin',
+  'lasso',
+  'lean',
+  'lesscss',
+  'lighttpd-configuration-file',
+  'limbo',
+  'liquid',
+  'literate-agda',
+  'literate-cryptol',
+  'literate-haskell',
+  'literate-idris',
+  'livescript',
+  'llvm',
+  'logos',
+  'logtalk',
+  'lsl',
+  'lua',
+  'makefile',
+  'mako',
+  'maql',
+  'mask',
+  'mason',
+  'mathematica',
+  'matlab',
+  'matlab-session',
+  'minid',
+  'modelica',
+  'modula-2',
+  'moinmoin/trac-wiki-markup',
+  'monkey',
+  'moocode',
+  'moonscript',
+  'mozhashpreproc',
+  'mozpercentpreproc',
+  'mql',
+  'mscgen',
+  'msdos-session',
+  'mupad',
+  'mxml',
+  'myghty',
+  'mysql',
+  'nasm',
+  'nemerle',
+  'nesc',
+  'newlisp',
+  'newspeak',
+  'nginx-configuration-file',
+  'nimrod',
+  'nit',
+  'nix',
+  'nsis',
+  'numpy',
+  'objdump',
+  'objdump-nasm',
+  'objective-c',
+  'objective-c++',
+  'objective-j',
+  'ocaml',
+  'octave',
+  'odin',
+  'ooc',
+  'opa',
+  'openedge-abl',
+  'pacmanconf',
+  'pan',
+  'parasail',
+  'pawn',
+  'perl',
+  'perl6',
+  'php',
+  'pig',
+  'pike',
+  'pkgconfig',
+  'pl/pgsql',
+  'postgresql-console-(psql)',
+  'postgresql-sql-dialect',
+  'postscript',
+  'povray',
+  'powershell',
+  'powershell-session',
+  'praat',
+  'prolog',
+  'properties',
+  'protocol-buffer',
+  'puppet',
+  'pypy-log',
+  'python',
+  'python-3',
+  'python-3.0-traceback',
+  'python-console-session',
+  'python-traceback',
+  'qbasic',
+  'qml',
+  'qvto',
+  'racket',
+  'ragel',
+  'ragel-in-c-host',
+  'ragel-in-cpp-host',
+  'ragel-in-d-host',
+  'ragel-in-java-host',
+  'ragel-in-objective-c-host',
+  'ragel-in-ruby-host',
+  'raw-token-data',
+  'rconsole',
+  'rd',
+  'rebol',
+  'red',
+  'redcode',
+  'reg',
+  'resourcebundle',
+  'restructuredtext',
+  'rexx',
+  'rhtml',
+  'roboconf-graph',
+  'roboconf-instances',
+  'robotframework',
+  'rpmspec',
+  'rql',
+  'rsl',
+  'ruby',
+  'ruby-irb-session',
+  'rust',
+  's',
+  'sass',
+  'scala',
+  'scalate-server-page',
+  'scaml',
+  'scheme',
+  'scilab',
+  'scss',
+  'shen',
+  'slim',
+  'smali',
+  'smalltalk',
+  'smarty',
+  'snobol',
+  'sourcepawn',
+  'sparql',
+  'sql',
+  'sqlite3con',
+  'squidconf',
+  'stan',
+  'standard-ml',
+  'supercollider',
+  'swift',
+  'swig',
+  'systemverilog',
+  'tads-3',
+  'tap',
+  'tcl',
+  'tcsh',
+  'tcsh-session',
+  'tea',
+  'termcap',
+  'terminfo',
+  'terraform',
+  'tex',
+  'text-only',
+  'thrift',
+  'todotxt',
+  'trafficscript',
+  'treetop',
+  'turtle',
+  'twig',
+  'typescript',
+  'urbiscript',
+  'vala',
+  'vb.net',
+  'vctreestatus',
+  'velocity',
+  'verilog',
+  'vgl',
+  'vhdl',
+  'viml',
+  'x10',
+  'xml',
+  'xml+cheetah',
+  'xml+django/jinja',
+  'xml+evoque',
+  'xml+lasso',
+  'xml+mako',
+  'xml+myghty',
+  'xml+php',
+  'xml+ruby',
+  'xml+smarty',
+  'xml+velocity',
+  'xquery',
+  'xslt',
+  'xtend',
+  'xul+mozpreproc',
+  'yaml',
+  'yaml+jinja',
+  'zephir'
+);
+
+-- Language metadata
+create table content_language (
+  id sha1 primary key references content(sha1) not null,
+  lang languages not null
+);
+
+comment on table content_language is 'Language information on a raw content';
+comment on column content_language.lang is 'Language information';
diff --git a/sql/upgrades/087.sql b/sql/upgrades/087.sql
index f85b0863..83c168db 100644
--- a/sql/upgrades/087.sql
+++ b/sql/upgrades/087.sql
@@ -1,56 +1,467 @@
 -- SWH DB schema upgrade
 -- from_version: 86
 -- to_version: 87
 -- description: indexer: Add indexer's new content properties table
 
 insert into dbversion(version, release, description)
       values(87, now(), 'Work In Progress');
 
 -- Properties (mimetype, encoding, etc...)
 create table content_mimetype (
 id sha1 primary key references content(sha1) not null,
   mimetype bytea not null,
   encoding bytea not null
 );
 
 comment on table content_mimetype is 'Metadata associated to a raw content';
 comment on column content_mimetype.mimetype is 'Raw content Mimetype';
 comment on column content_mimetype.encoding is 'Raw content encoding';
 
 -- check which entries of tmp_bytea are missing from content_mimetype
 --
 -- operates in bulk: 0. swh_mktemp_bytea(), 1. COPY to tmp_bytea,
 -- 2. call this function
 create or replace function swh_mimetype_missing()
     returns setof sha1
     language plpgsql
 as $$
 begin
     return query
 	(select id::sha1 from tmp_bytea as tmp
 	 where not exists
 	     (select 1 from content_mimetype as c where c.id = tmp.id));
     return;
 end
 $$;
 
 comment on function swh_mimetype_missing() IS 'Filter missing mimetype';
 
 -- add tmp_content_mimetype entries to content_mimetype, skipping duplicates
 --
 -- operates in bulk: 0. swh_mktemp(content_mimetype), 1. COPY to tmp_content_mimetype,
 -- 2. call this function
 create or replace function swh_mimetype_add()
     returns void
     language plpgsql
 as $$
 begin
     insert into content_mimetype (id, mimetype, encoding)
 	select id, mimetype, encoding
 	from tmp_content_mimetype
         on conflict do nothing;
     return;
 end
 $$;
 
 COMMENT ON FUNCTION swh_mimetype_add() IS 'Add new content mimetype';
+
+create type languages as enum (
+  'abap',
+  'abnf',
+  'actionscript',
+  'actionscript-3',
+  'ada',
+  'adl',
+  'agda',
+  'alloy',
+  'ambienttalk',
+  'antlr',
+  'antlr-with-actionscript-target',
+  'antlr-with-c#-target',
+  'antlr-with-cpp-target',
+  'antlr-with-java-target',
+  'antlr-with-objectivec-target',
+  'antlr-with-perl-target',
+  'antlr-with-python-target',
+  'antlr-with-ruby-target',
+  'apacheconf',
+  'apl',
+  'applescript',
+  'arduino',
+  'aspectj',
+  'aspx-cs',
+  'aspx-vb',
+  'asymptote',
+  'autohotkey',
+  'autoit',
+  'awk',
+  'base-makefile',
+  'bash',
+  'bash-session',
+  'batchfile',
+  'bbcode',
+  'bc',
+  'befunge',
+  'blitzbasic',
+  'blitzmax',
+  'bnf',
+  'boo',
+  'boogie',
+  'brainfuck',
+  'bro',
+  'bugs',
+  'c',
+  'c#',
+  'c++',
+  'c-objdump',
+  'ca65-assembler',
+  'cadl',
+  'camkes',
+  'cbm-basic-v2',
+  'ceylon',
+  'cfengine3',
+  'cfstatement',
+  'chaiscript',
+  'chapel',
+  'cheetah',
+  'cirru',
+  'clay',
+  'clojure',
+  'clojurescript',
+  'cmake',
+  'cobol',
+  'cobolfree',
+  'coffeescript',
+  'coldfusion-cfc',
+  'coldfusion-html',
+  'common-lisp',
+  'component-pascal',
+  'coq',
+  'cpp-objdump',
+  'cpsa',
+  'crmsh',
+  'croc',
+  'cryptol',
+  'csound-document',
+  'csound-orchestra',
+  'csound-score',
+  'css',
+  'css+django/jinja',
+  'css+genshi-text',
+  'css+lasso',
+  'css+mako',
+  'css+mozpreproc',
+  'css+myghty',
+  'css+php',
+  'css+ruby',
+  'css+smarty',
+  'cuda',
+  'cypher',
+  'cython',
+  'd',
+  'd-objdump',
+  'darcs-patch',
+  'dart',
+  'debian-control-file',
+  'debian-sourcelist',
+  'delphi',
+  'dg',
+  'diff',
+  'django/jinja',
+  'docker',
+  'dtd',
+  'duel',
+  'dylan',
+  'dylan-session',
+  'dylanlid',
+  'earl-grey',
+  'easytrieve',
+  'ebnf',
+  'ec',
+  'ecl',
+  'eiffel',
+  'elixir',
+  'elixir-iex-session',
+  'elm',
+  'emacslisp',
+  'embedded-ragel',
+  'erb',
+  'erlang',
+  'erlang-erl-session',
+  'evoque',
+  'ezhil',
+  'factor',
+  'fancy',
+  'fantom',
+  'felix',
+  'fish',
+  'fortran',
+  'fortranfixed',
+  'foxpro',
+  'fsharp',
+  'gap',
+  'gas',
+  'genshi',
+  'genshi-text',
+  'gettext-catalog',
+  'gherkin',
+  'glsl',
+  'gnuplot',
+  'go',
+  'golo',
+  'gooddata-cl',
+  'gosu',
+  'gosu-template',
+  'groff',
+  'groovy',
+  'haml',
+  'handlebars',
+  'haskell',
+  'haxe',
+  'hexdump',
+  'html',
+  'html+cheetah',
+  'html+django/jinja',
+  'html+evoque',
+  'html+genshi',
+  'html+handlebars',
+  'html+lasso',
+  'html+mako',
+  'html+myghty',
+  'html+php',
+  'html+smarty',
+  'html+twig',
+  'html+velocity',
+  'http',
+  'hxml',
+  'hy',
+  'hybris',
+  'idl',
+  'idris',
+  'igor',
+  'inform-6',
+  'inform-6-template',
+  'inform-7',
+  'ini',
+  'io',
+  'ioke',
+  'irc-logs',
+  'isabelle',
+  'j',
+  'jade',
+  'jags',
+  'jasmin',
+  'java',
+  'java-server-page',
+  'javascript',
+  'javascript+cheetah',
+  'javascript+django/jinja',
+  'javascript+genshi-text',
+  'javascript+lasso',
+  'javascript+mako',
+  'javascript+mozpreproc',
+  'javascript+myghty',
+  'javascript+php',
+  'javascript+ruby',
+  'javascript+smarty',
+  'jcl',
+  'json',
+  'json-ld',
+  'julia',
+  'julia-console',
+  'kal',
+  'kconfig',
+  'koka',
+  'kotlin',
+  'lasso',
+  'lean',
+  'lesscss',
+  'lighttpd-configuration-file',
+  'limbo',
+  'liquid',
+  'literate-agda',
+  'literate-cryptol',
+  'literate-haskell',
+  'literate-idris',
+  'livescript',
+  'llvm',
+  'logos',
+  'logtalk',
+  'lsl',
+  'lua',
+  'makefile',
+  'mako',
+  'maql',
+  'mask',
+  'mason',
+  'mathematica',
+  'matlab',
+  'matlab-session',
+  'minid',
+  'modelica',
+  'modula-2',
+  'moinmoin/trac-wiki-markup',
+  'monkey',
+  'moocode',
+  'moonscript',
+  'mozhashpreproc',
+  'mozpercentpreproc',
+  'mql',
+  'mscgen',
+  'msdos-session',
+  'mupad',
+  'mxml',
+  'myghty',
+  'mysql',
+  'nasm',
+  'nemerle',
+  'nesc',
+  'newlisp',
+  'newspeak',
+  'nginx-configuration-file',
+  'nimrod',
+  'nit',
+  'nix',
+  'nsis',
+  'numpy',
+  'objdump',
+  'objdump-nasm',
+  'objective-c',
+  'objective-c++',
+  'objective-j',
+  'ocaml',
+  'octave',
+  'odin',
+  'ooc',
+  'opa',
+  'openedge-abl',
+  'pacmanconf',
+  'pan',
+  'parasail',
+  'pawn',
+  'perl',
+  'perl6',
+  'php',
+  'pig',
+  'pike',
+  'pkgconfig',
+  'pl/pgsql',
+  'postgresql-console-(psql)',
+  'postgresql-sql-dialect',
+  'postscript',
+  'povray',
+  'powershell',
+  'powershell-session',
+  'praat',
+  'prolog',
+  'properties',
+  'protocol-buffer',
+  'puppet',
+  'pypy-log',
+  'python',
+  'python-3',
+  'python-3.0-traceback',
+  'python-console-session',
+  'python-traceback',
+  'qbasic',
+  'qml',
+  'qvto',
+  'racket',
+  'ragel',
+  'ragel-in-c-host',
+  'ragel-in-cpp-host',
+  'ragel-in-d-host',
+  'ragel-in-java-host',
+  'ragel-in-objective-c-host',
+  'ragel-in-ruby-host',
+  'raw-token-data',
+  'rconsole',
+  'rd',
+  'rebol',
+  'red',
+  'redcode',
+  'reg',
+  'resourcebundle',
+  'restructuredtext',
+  'rexx',
+  'rhtml',
+  'roboconf-graph',
+  'roboconf-instances',
+  'robotframework',
+  'rpmspec',
+  'rql',
+  'rsl',
+  'ruby',
+  'ruby-irb-session',
+  'rust',
+  's',
+  'sass',
+  'scala',
+  'scalate-server-page',
+  'scaml',
+  'scheme',
+  'scilab',
+  'scss',
+  'shen',
+  'slim',
+  'smali',
+  'smalltalk',
+  'smarty',
+  'snobol',
+  'sourcepawn',
+  'sparql',
+  'sql',
+  'sqlite3con',
+  'squidconf',
+  'stan',
+  'standard-ml',
+  'supercollider',
+  'swift',
+  'swig',
+  'systemverilog',
+  'tads-3',
+  'tap',
+  'tcl',
+  'tcsh',
+  'tcsh-session',
+  'tea',
+  'termcap',
+  'terminfo',
+  'terraform',
+  'tex',
+  'text-only',
+  'thrift',
+  'todotxt',
+  'trafficscript',
+  'treetop',
+  'turtle',
+  'twig',
+  'typescript',
+  'urbiscript',
+  'vala',
+  'vb.net',
+  'vctreestatus',
+  'velocity',
+  'verilog',
+  'vgl',
+  'vhdl',
+  'viml',
+  'x10',
+  'xml',
+  'xml+cheetah',
+  'xml+django/jinja',
+  'xml+evoque',
+  'xml+lasso',
+  'xml+mako',
+  'xml+myghty',
+  'xml+php',
+  'xml+ruby',
+  'xml+smarty',
+  'xml+velocity',
+  'xquery',
+  'xslt',
+  'xtend',
+  'xul+mozpreproc',
+  'yaml',
+  'yaml+jinja',
+  'zephir'
+);
+
+-- Language metadata
+create table content_language (
+  id sha1 primary key references content(sha1) not null,
+  lang languages not null
+);
+
+comment on table content_language is 'Language information on a raw content';
+comment on column content_language.lang is 'Language information';