feat(wordpress): set post category from title and tag rules

Published articles carried no category, so WordPress filed all of them
under the catch-all "Allgemein" - 941 of 955 posts by the time this was
noticed. The rules here mirror the one-off backfill of 2026-07-31 and
reproduce its result on all 955 posts exactly.

Matching is done on word boundaries rather than plain substrings, which
otherwise filed a campsite in Klagenfurt under "Recht & Vorschriften" via
the keyword "klage". German compounds opt in explicitly with a trailing
"*". A clear discount signal takes precedence over the product topic,
because product tags otherwise outnumber it.

Unknown slugs are never auto-created: unlike tags, the category set is
curated in WordPress, so a mismatch should surface rather than spawn a
new category. Articles that match no rule stay uncategorised on purpose.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

backend/app/categorize.py

@@ -0,0 +1,237 @@
+"""Assign a WordPress category to an article.
+
+The rules mirror the one-off backfill of 2026-07-31 that moved 955 existing
+posts out of the catch-all "Allgemein" category, so newly published articles
+land in the same buckets as the archive.
+
+Matching notes:
+- Keywords match on a word boundary. Plain substring matching is wrong here:
+  "klage" would match the city name "Klagenfurt".
+- A trailing "*" opts a keyword into German compound nouns, so "campingplatz*"
+  also matches "Campingplatzbetreiber".
+- Tags weigh more than the title. Tags were chosen deliberately, while titles
+  often carry incidental place names.
+"""
+
+from __future__ import annotations
+
+import re
+from collections.abc import Sequence
+
+# Category key -> WordPress category slug.
+CATEGORY_SLUGS: dict[str, str] = {
+    "angebote-rabatte": "angebote-rabatte",
+    "in-eigener-sache": "in-eigener-sache",
+    "recht-vorschriften": "recht-vorschriften",
+    "fahrzeug-technik": "fahrzeug",
+    "ausruestung-tests": "ausruestung-tests",
+    "campingplaetze": "campingplaetze",
+    "stellplaetze": "stellplaetze",
+    "news-branche": "news",
+    "reiseziele": "reiseziele",
+    "camping-tipps": "camping-tipps",
+    "vanlife": "vanlife",
+}
+
+# Ordered by priority: on a points tie the earlier entry wins.
+_RULES: tuple[tuple[str, tuple[tuple[str, int], ...]], ...] = (
+    ("angebote-rabatte", (
+        ("amazon sale", 3), ("amazon-sale", 3), ("amazon-angebote", 3), ("im sale", 3),
+        ("rabatt*", 3), ("schnaeppchen*", 3), ("prime day", 3), ("black friday", 3),
+        ("gutschein*", 3), ("sparangebot*", 3), ("top-angebot*", 3), ("sommerangebot*", 3),
+        ("knaller", 3), ("ausverkauf", 3), ("tiefpreis*", 3), ("rekordpreis*", 3),
+        ("preissturz", 3), ("bestpreis*", 3), ("deal", 2), ("deals", 2), ("lidl", 2),
+        ("aldi", 2), ("reduziert", 2), ("sale", 1), ("prozent auf", 3), ("guenstiger*", 1),
+    )),
+    ("in-eigener-sache", (
+        ("vanityontour", 3), ("vanitycast", 3), ("expense logbook", 3),
+        ("jahresrueckblick", 3), ("rueckblick", 2), ("website", 3), ("in eigener sache", 3),
+        ("blog", 2), ("discord", 3), ("newsletter", 2), ("appstore", 2), ("app store", 2),
+        ("ausfall", 2), ("stoerung", 2), ("podcast", 2), ("campertag", 3), ("styyl", 3),
+    )),
+    ("recht-vorschriften", (
+        ("stvo", 3), ("fuehrerschein*", 3), ("bussgeld*", 3), ("gesetz*", 3),
+        ("vorschrift*", 3), ("verkehrsrecht*", 3), ("versicherungsschutz", 3),
+        ("tempolimit", 3), ("promillegrenze", 3), ("maut", 3), ("urteil*", 3),
+        ("rechtslage", 3), ("abgemahnt", 3), ("bauantrag", 3), ("baurecht", 3),
+        ("genehmigung*", 2), ("verboten", 2), ("erlaubt", 2), ("strafe*", 2), ("haftung", 2),
+        ("illegal", 2), ("stellplatzverordnung", 3), ("datenschutz", 2), ("kurtaxe", 3),
+        ("uebernachtungssteuer", 3), ("kfz-versicherung", 3), ("kfz versicherung", 3),
+        ("versicherung*", 1), ("handyverbot", 3), ("regeln", 1),
+        ("landschaftsschutzgebiet", 2),
+    )),
+    ("fahrzeug-technik", (
+        ("wohnmobil*", 3), ("wohnwagen*", 3), ("reisemobil*", 3), ("kastenwagen", 3),
+        ("camper van", 3), ("camper-van*", 3), ("truma", 3), ("klimaanlage*", 3),
+        ("standheizung*", 3), ("energieversorgung", 3), ("ecoflow", 3), ("jackery", 3),
+        ("powerstation*", 3), ("solar*", 3), ("batterie*", 3), ("wechselrichter", 3),
+        ("notstrom", 3), ("generator", 3), ("stromversorgung", 3), ("umbau", 3), ("ausbau", 3),
+        ("selbstausbau", 3), ("fahrverhalten", 3), ("reifen", 3), ("gasanlage*", 3),
+        ("gasflasche*", 3), ("werkstatt", 3), ("tuev", 3), ("caravaning", 3), ("caravan", 2),
+        ("dometic", 3), ("anhaengerkupplung", 3), ("chassis", 3), ("dieselheizung*", 3),
+        ("wasserpumpe*", 3), ("osram", 3), ("auffahrkeil*", 3), ("mover", 3), ("dachluke*", 3),
+        ("aufbau", 1), ("heizung", 2), ("strom", 2), ("motor", 2), ("led", 2), ("autark", 2),
+        ("ladedose", 3), ("bordtechnik", 3), ("gewicht", 1), ("auflastung", 3),
+        ("wiegeaktion", 3), ("gebrauchtwagen*", 3), ("kfz", 2), ("gasversorgung", 3),
+        ("flaschengas*", 3), ("marder*", 3), ("reparatur", 2), ("diy", 2),
+    )),
+    ("ausruestung-tests", (
+        ("kuehlbox*", 3), ("kuehltasche*", 3), ("schlafsack*", 3), ("schlafsaecke", 3),
+        ("dachzelt*", 3), ("campingbett*", 3), ("zelt*", 3), ("gaskocher", 3),
+        ("campingkocher", 3), ("kopfkissen", 3), ("campingstuhl*", 3), ("campingstuehle", 3),
+        ("sonnensegel", 3), ("luftmatratze*", 3), ("isomatte*", 3), ("campingdusche*", 3),
+        ("produkttest*", 3), ("testbericht*", 3), ("im test", 3), ("getestet", 3),
+        ("decathlon", 3), ("coleman", 3), ("campingaz", 3), ("quechua", 3), ("ausruestung", 3),
+        ("campingausruestung", 3), ("gadget*", 3), ("markise*", 3), ("nachttisch*", 3),
+        ("geschirr", 3), ("grill*", 3), ("campingmoebel", 3), ("stirnlampe*", 3),
+        ("powerbank*", 3), ("wasserkanister", 3), ("vorzelt*", 3), ("haengematte*", 3),
+        ("campingkueche*", 3), ("campingtisch*", 3), ("camping-helfer", 3),
+        ("kaffeemaschine*", 3), ("campingtoilette*", 3), ("rucksack*", 3), ("wanderschuh*", 3),
+        ("thermacell", 3), ("kabeltrommel*", 3), ("fernglas", 3), ("fernglaeser", 3),
+        ("tarp", 3), ("lichterkette*", 3), ("klapptisch*", 3), ("uv-schutz", 2),
+        ("wasserdicht*", 2), ("belueftung", 2), ("kaufberatung", 3), ("marktcheck", 3),
+        ("mueckenschutz", 3), ("sonnenschutz", 2), ("ventilator*", 3), ("campinggeschirr", 3),
+        ("campingzelt*", 3), ("wurfzelt*", 3), ("tunnelzelt*", 3), ("familienzelt*", 3),
+        ("trekkingzelt*", 3), ("aufblasbare*", 2), ("trenntoilette*", 3),
+        ("kassettentoilette*", 3), ("toilette*", 2), ("gaswarner", 3), ("rauchmelder", 3),
+        ("feuerloescher", 3), ("co melder", 3), ("router", 3), ("mobilfunk", 3), ("wlan", 3),
+        ("lte", 3), ("5g", 3), ("internet", 2), ("buchtipp*", 2),
+    )),
+    ("campingplaetze", (
+        ("campingplatz*", 3), ("campingplaetze", 3), ("5-sterne*", 3), ("fuenf sterne", 3),
+        ("adac-superplatz", 3), ("adac bewertung", 3), ("adac-bewertung", 3),
+        ("superplatz*", 3), ("glamping", 3), ("wellness-camping", 3), ("suedsee-camp", 3),
+        ("wirthshof", 3), ("trekking-camp*", 3), ("naturcamping*", 3), ("campingpark*", 3),
+        ("ferienpark*", 3), ("sanitaer*", 3), ("platz des jahres", 3), ("campingdorf", 3),
+        ("campinganlage*", 3), ("campingplatzbetreiber", 3), ("campingfuehrer", 3),
+        ("pincamp", 3), ("dauercamp*", 3), ("camping-check", 3), ("campingresort", 3),
+        ("stammgaeste", 2), ("kinderanimation", 2), ("resort", 2), ("wellness", 2),
+        ("campingplatz-ranking", 3), ("platzbewertung", 3),
+    )),
+    ("stellplaetze", (
+        ("stellplatz*", 3), ("stellplaetze", 3), ("freistehen", 3), ("wildcamp*", 3),
+        ("camping-car park", 3), ("wohnmobilstellplatz*", 3), ("wohnmobilstellplaetze", 3),
+        ("wohnmobilhafen", 3), ("wohnmobil-stellplaetze", 3), ("stellplatzfuehrer", 3),
+        ("uebernachtungsmoeglichkeit*", 2), ("stellplatz-radar", 3), ("parkplatz", 1),
+        ("parken", 1), ("church4night", 3), ("raststaette*", 2), ("autohof*", 2),
+    )),
+    ("news-branche", (
+        ("bvcd", 3), ("bundesverband", 3), ("camping-boom", 3), ("campingboom", 3),
+        ("uebernachtungszahlen", 3), ("preisanalyse", 3), ("preisentwicklung", 3),
+        ("campingpreise", 3), ("preisanstieg", 3), ("preiserhoehung*", 3), ("destatis", 3),
+        ("camping-trends", 3), ("campingtrend*", 3), ("marktanalyse", 3), ("caravan salon", 3),
+        ("messe", 3), ("promobil", 3), ("insolvenz", 3), ("saisonstart", 3),
+        ("jahreszahlen", 3), ("uebernachtungen", 3), ("rekordzahl", 3), ("statistik*", 3),
+        ("umfrage", 3), ("studie", 3), ("branche", 3), ("investitionen", 2), ("tourismus", 2),
+        ("nachfrage", 2), ("bilanz", 2), ("rekord", 2), ("auszeichnung", 2),
+        ("ausgezeichnet", 2), ("preisvergleich", 2), ("eroeffnung", 2), ("eroeffnet", 2),
+        ("uebernimmt", 2), ("verkauft", 2), ("pressemeldung", 2), ("feuerwehr", 3),
+        ("polizei", 2), ("unfall", 3), ("verletzte", 3), ("hochwasser", 2), ("evakuiert", 3),
+        ("veranstaltung*", 2),
+    )),
+    ("reiseziele", (
+        ("nordsee", 3), ("ostsee", 3), ("niedersachsen", 3), ("bodensee", 3),
+        ("lueneburger heide", 3), ("thueringen", 3), ("harz", 3), ("italien", 3),
+        ("kroatien", 3), ("schweiz", 3), ("oesterreich", 3), ("norwegen", 3), ("schweden", 3),
+        ("niederlande", 3), ("holland", 3), ("ruegen", 3), ("fehmarn", 3), ("gardasee", 3),
+        ("schwarzwald", 3), ("sauerland", 3), ("edersee", 3), ("bayern", 3), ("hessen", 3),
+        ("nrw", 3), ("mecklenburg*", 3), ("baden-wuerttemberg", 3), ("adriakueste", 3),
+        ("daenemark", 3), ("frankreich", 3), ("spanien", 3), ("portugal", 3), ("slowenien", 3),
+        ("weserradweg", 3), ("waldeck*", 3), ("sylt", 3), ("usedom", 3), ("allgaeu", 3),
+        ("eifel", 3), ("mosel", 3), ("alpen", 3), ("toskana", 3), ("brandenburg", 3),
+        ("sachsen", 3), ("schleswig-holstein", 3), ("rheinland-pfalz", 3), ("saarland", 3),
+        ("tirol", 3), ("suedtirol", 3), ("belgien", 3), ("tschechien", 3), ("polen", 3),
+        ("ungarn", 3), ("pyrenaeen", 3), ("nationalpark*", 3), ("reiseziel*", 3),
+        ("rundreise*", 3), ("roadtrip*", 3), ("reisebericht*", 3), ("ausflugsziel*", 3),
+        ("kurztrip*", 3), ("europa", 2), ("kueste", 2), ("region", 1), ("uckermark", 3),
+        ("lausitz", 3), ("schwaebische alb", 3), ("ausflug*", 2), ("geheimtipp*", 2),
+        ("uebersee", 2), ("kanada", 3),
+    )),
+    ("camping-tipps", (
+        ("tipp", 3), ("tipps", 3), ("tricks", 3), ("ratgeber", 3), ("anleitung", 3),
+        ("checkliste", 3), ("packliste", 3), ("buchungstipp*", 3), ("reiseplanung", 3),
+        ("urlaubsplanung", 3), ("camping apps", 3), ("nebensaison", 3), ("wintercamping", 3),
+        ("campingsaison", 3), ("camping-saison", 3), ("angrillen", 3), ("reisetipp*", 3),
+        ("erste hilfe", 3), ("diebstahlschutz", 3), ("so geht", 2), ("so funktioniert", 2),
+        ("worauf", 2), ("das sollten", 2), ("muss man wissen", 2), ("wie man", 2),
+        ("vermeiden", 2), ("hygiene", 2), ("sicherheit", 2), ("vorbereitung", 2), ("hitze", 2),
+        ("wetter", 1), ("guide", 2), ("mythos", 2), ("mythen", 2), ("mit hund", 2),
+        ("hundefreundlich*", 2),
+    )),
+    ("vanlife", (
+        ("vanlife", 3), ("van-life", 3), ("van life", 3), ("minimalismus", 3),
+        ("digitale nomaden", 3), ("aussteiger", 3), ("slow travel", 3),
+        ("campergemeinschaft", 3), ("camper-gemeinschaft", 3), ("lebensgefuehl", 3),
+        ("auszeit", 2), ("freiheit", 2), ("abenteuer", 2), ("gedanken", 2),
+        ("nachhaltigkeit", 2),
+    )),
+)
+
+_PRIORITY = {key: i for i, (key, _) in enumerate(_RULES)}
+
+# A clear discount signal decides on its own: a tent on sale is first of all an
+# offer. Otherwise "Ausruestung & Tests" wins on the sheer number of product
+# tags and the offers category stays nearly empty.
+_OFFER_KEY = "angebote-rabatte"
+_OFFER_OVERRIDE_MIN_WEIGHT = 3
+
+
+def _normalise(text: str) -> str:
+    text = text.lower()
+    for src, dst in (("\u00e4", "ae"), ("\u00f6", "oe"), ("\u00fc", "ue"), ("\u00df", "ss")):
+        text = text.replace(src, dst)
+    text = text.replace("&", " ").replace("&", " ")
+    text = re.sub(r"[\u201e\u201c\u201d\u2018\u2019\u00ab\u00bb\"']", " ", text)
+    text = text.replace("\u2013", "-").replace("\u2014", "-")
+    return re.sub(r"\s+", " ", text).strip()
+
+
+def _compile(keyword: str) -> re.Pattern[str]:
+    compound = keyword.endswith("*")
+    core = _normalise(keyword[:-1] if compound else keyword)
+    body = re.escape(core).replace(r"\ ", r"\s+")
+    tail = r"[a-z0-9]*" if compound else r"(?![a-z0-9])"
+    return re.compile(r"(?<![a-z0-9])" + body + tail)
+
+
+_PATTERNS: dict[str, tuple[tuple[re.Pattern[str], int], ...]] = {
+    key: tuple((_compile(kw), weight) for kw, weight in keywords) for key, keywords in _RULES
+}
+
+
+def classify(title: str, tags: Sequence[str] | None = None) -> str | None:
+    """Return a category key, or None when no rule matches.
+
+    Callers should leave the category unset in that case so the article stays
+    visible in WordPress' default category instead of being filed wrongly.
+    """
+    title_text = _normalise(title or "")
+    tag_text = _normalise(" | ".join(tags or []))
+
+    scores: dict[str, int] = {}
+    for key, patterns in _PATTERNS.items():
+        total = 0
+        for pattern, weight in patterns:
+            if pattern.search(tag_text):
+                total += 3 * weight
+            if pattern.search(title_text):
+                total += 2 * weight
+        if total:
+            scores[key] = total
+
+    if not scores:
+        return None
+
+    for pattern, weight in _PATTERNS[_OFFER_KEY]:
+        if weight >= _OFFER_OVERRIDE_MIN_WEIGHT and (
+            pattern.search(tag_text) or pattern.search(title_text)
+        ):
+            return _OFFER_KEY
+
+    return max(scores.items(), key=lambda item: (item[1], -_PRIORITY[item[0]]))[0]
+
+
+def category_slug(title: str, tags: Sequence[str] | None = None) -> str | None:
+    """Return the WordPress category slug for an article, or None."""
+    key = classify(title, tags)
+    return CATEGORY_SLUGS.get(key) if key else None

backend/app/wordpress.py

@@ -12,6 +12,7 @@ from html import unescape as _html_unescape
 from urllib.parse import quote_plus, urlparse
 from urllib.request import Request, urlopen
 
+from . import categorize
 from .config import get_settings
 
 
@@ -137,6 +138,48 @@ def _resolve_wp_tag_ids(*, base_url: str, auth_header: str, tags: list[str]) ->
     return ids
 
 
+_category_id_cache: dict[str, int | None] = {}
+
+
+def _resolve_wp_category_id(*, base_url: str, auth_header: str, slug: str) -> int | None:
+    """Look up a WordPress category by slug.
+
+    Unlike tags, categories are never created on the fly: the set is curated in
+    WordPress, so an unknown slug means the rules and the site drifted apart and
+    should be fixed there, not silently papered over with a new category.
+    """
+    if slug in _category_id_cache:
+        return _category_id_cache[slug]
+
+    try:
+        result = _wp_request(
+            base_url=base_url,
+            auth_header=auth_header,
+            method="GET",
+            endpoint=f"categories?slug={quote_plus(slug)}&per_page=1",
+        )
+    except Exception as exc:
+        # Do not cache transient failures - the next article should retry.
+        _logger.warning("Kategorie-Abfrage für '%s' fehlgeschlagen: %s", slug, exc)
+        return None
+
+    category_id: int | None = None
+    if isinstance(result, list):
+        for row in result:
+            if not isinstance(row, dict):
+                continue
+            rid = int(row.get("id", 0) or 0)
+            if rid > 0:
+                category_id = rid
+                break
+
+    if category_id is None:
+        _logger.warning("Kategorie mit Slug '%s' existiert nicht in WordPress", slug)
+
+    _category_id_cache[slug] = category_id
+    return category_id
+
+
 _BLOCKED_IMAGE_EXTS = {".svg", ".gif", ".ico", ".webp"}
 _logger = logging.getLogger(__name__)
 
@@ -508,14 +551,33 @@ def publish_article_draft(article: dict[str, Any]) -> tuple[int, str | None]:
             pass
 
     wp_post_id = article.get("wp_post_id")
+    tag_names = _selected_tags_from_meta(article.get("meta_json"))
     tag_ids = _resolve_wp_tag_ids(
         base_url=settings.wordpress_base_url,
         auth_header=auth,
-        tags=_selected_tags_from_meta(article.get("meta_json")),
+        tags=tag_names,
     )
     if tag_ids:
         payload["tags"] = tag_ids
 
+    # Without an explicit category WordPress files everything under "Allgemein".
+    # Leaving it unset when no rule matches is deliberate: a wrong category is
+    # harder to spot later than a handful of posts in the catch-all.
+    slug = categorize.category_slug(title, tag_names)
+    if slug:
+        category_id = _resolve_wp_category_id(
+            base_url=settings.wordpress_base_url,
+            auth_header=auth,
+            slug=slug,
+        )
+        if category_id:
+            payload["categories"] = [category_id]
+    else:
+        _logger.info(
+            "Keine Kategorie-Regel für Artikel #%s (%s) - bleibt in der Standardkategorie",
+            article.get("id"), title[:60],
+        )
+
     if wp_post_id:
         result = _wp_request(
             base_url=settings.wordpress_base_url,

backend/tests/test_categorize.py

@@ -0,0 +1,61 @@
+import unittest
+
+from backend.app.categorize import CATEGORY_SLUGS, category_slug, classify
+
+
+class TestCategorize(unittest.TestCase):
+    def test_tags_decide_the_category(self) -> None:
+        self.assertEqual(
+            classify("Neuer Platz am Wasser", ["Campingplatz", "5-Sterne-Campingplätze"]),
+            "campingplaetze",
+        )
+        self.assertEqual(classify("Unterwegs im Norden", ["Nordsee", "Niedersachsen"]), "reiseziele")
+        self.assertEqual(classify("Update vom Van", ["Wohnmobil", "Truma", "Solar"]), "fahrzeug-technik")
+
+    def test_title_alone_is_enough(self) -> None:
+        self.assertEqual(classify("Dometic CFX5 45 im Test: Top-Kühlbox", []), "ausruestung-tests")
+        self.assertEqual(classify("Führerscheine müssen getauscht werden", []), "recht-vorschriften")
+
+    def test_discount_signal_beats_the_product_topic(self) -> None:
+        # Without the override this lands in "Ausruestung & Tests", because the
+        # product tags outnumber the single discount signal.
+        self.assertEqual(
+            classify("Campingzelte bei Amazon im Sale: bis zu 55 %", ["Zelte", "Schlafsack", "Rabatt"]),
+            "angebote-rabatte",
+        )
+
+    def test_keywords_respect_word_boundaries(self) -> None:
+        # "klage" must not match the city name "Klagenfurt" - plain substring
+        # matching filed this campsite opening under "Recht & Vorschriften".
+        self.assertEqual(
+            classify("Falkensteiner Camping Wörthersee startet in die erste Saison",
+                     ["Campingplatz", "Klagenfurt", "Saisonstart"]),
+            "campingplaetze",
+        )
+
+    def test_compound_nouns_only_match_with_opt_in(self) -> None:
+        # "campingplatz*" is marked as a compound, so this still matches.
+        self.assertEqual(classify("Was Campingplatzbetreiber jetzt planen", []), "campingplaetze")
+
+    def test_returns_none_when_nothing_matches(self) -> None:
+        self.assertIsNone(classify("Weihnachten 2021", ["Weihnachten"]))
+        self.assertIsNone(category_slug("Weihnachten 2021", ["Weihnachten"]))
+
+    def test_umlauts_and_entities_are_normalised(self) -> None:
+        self.assertEqual(classify("Stellplätze an der Küste", []), "stellplaetze")
+        self.assertEqual(classify("Ausrüstung", ["Schlafsack"]), "ausruestung-tests")
+
+    def test_renamed_categories_keep_their_original_slug(self) -> None:
+        # Both were renamed in WordPress but kept the indexed archive URL.
+        self.assertEqual(CATEGORY_SLUGS["fahrzeug-technik"], "fahrzeug")
+        self.assertEqual(CATEGORY_SLUGS["news-branche"], "news")
+        self.assertEqual(category_slug("Update vom Van", ["Wohnmobil", "Truma"]), "fahrzeug")
+
+    def test_every_rule_maps_to_a_known_slug(self) -> None:
+        self.assertEqual(len(CATEGORY_SLUGS), 11)
+        for key, slug in CATEGORY_SLUGS.items():
+            self.assertTrue(slug and slug.islower(), f"{key} has a suspicious slug: {slug!r}")
+
+
+if __name__ == "__main__":
+    unittest.main()

backend/tests/test_wordpress.py

@@ -3,6 +3,7 @@ import unittest
 from unittest.mock import patch
 
 from backend.app import config as config_module
+from backend.app import wordpress as wordpress_module
 from backend.app.wordpress import publish_article_draft
 
 
@@ -12,6 +13,9 @@ class TestWordpressPublish(unittest.TestCase):
         os.environ["WORDPRESS_USERNAME"] = "wp-user"
         os.environ["WORDPRESS_APP_PASSWORD"] = "wp-pass"
         config_module.get_settings.cache_clear()
+        # The category lookup is cached for the process lifetime; without this
+        # one test would resolve a slug that the next one expects to be missing.
+        wordpress_module._category_id_cache.clear()
 
     def tearDown(self) -> None:
         for key in ("WORDPRESS_BASE_URL", "WORDPRESS_USERNAME", "WORDPRESS_APP_PASSWORD"):
@@ -134,6 +138,78 @@ class TestWordpressPublish(unittest.TestCase):
         self.assertIn("<!-- wp:list -->", content)
         self.assertNotIn("<!-- wp:html -->", content)
 
+    @patch("backend.app.wordpress._upload_featured_media")
+    @patch("backend.app.wordpress._wp_request")
+    def test_publish_sets_category_from_rules(self, mock_wp_request, mock_upload_media) -> None:
+        def _fake_wp_request(**kwargs):
+            endpoint = kwargs.get("endpoint", "")
+            method = kwargs.get("method", "")
+            if method == "GET" and endpoint.startswith("tags?search="):
+                return [{"id": 21, "name": "Kühlbox"}]
+            if method == "GET" and endpoint.startswith("categories?slug=ausruestung-tests"):
+                return [{"id": 77, "slug": "ausruestung-tests"}]
+            if method == "POST" and endpoint == "posts":
+                return {"id": 901, "link": "https://example.org/?p=901"}
+            return {}
+
+        mock_wp_request.side_effect = _fake_wp_request
+        article = {
+            "title": "Dometic CFX5 45 im Test: Top-Kühlbox für unterwegs",
+            "content_raw": "Inhalt",
+            "source_url": "https://example.com/source",
+            "canonical_url": "https://example.com/source",
+            "meta_json": '{"generated_tags":["Kühlbox"]}',
+        }
+        post_id, _ = publish_article_draft(article)
+        self.assertEqual(post_id, 901)
+        payload = [c for c in mock_wp_request.call_args_list if c.kwargs.get("endpoint") == "posts"][0].kwargs["payload"]
+        self.assertEqual(payload.get("categories"), [77])
+
+    @patch("backend.app.wordpress._upload_featured_media")
+    @patch("backend.app.wordpress._wp_request")
+    def test_publish_omits_category_when_no_rule_matches(self, mock_wp_request, mock_upload_media) -> None:
+        def _fake_wp_request(**kwargs):
+            if kwargs.get("method") == "POST" and kwargs.get("endpoint") == "posts":
+                return {"id": 902, "link": "https://example.org/?p=902"}
+            return {}
+
+        mock_wp_request.side_effect = _fake_wp_request
+        article = {
+            "title": "Weihnachten 2021",
+            "content_raw": "Inhalt",
+            "source_url": "https://example.com/source",
+            "canonical_url": "https://example.com/source",
+            "meta_json": '{"generated_tags":[]}',
+        }
+        publish_article_draft(article)
+        payload = [c for c in mock_wp_request.call_args_list if c.kwargs.get("endpoint") == "posts"][0].kwargs["payload"]
+        self.assertNotIn("categories", payload)
+        self.assertFalse(any("categories?slug=" in (c.kwargs.get("endpoint") or "")
+                             for c in mock_wp_request.call_args_list))
+
+    @patch("backend.app.wordpress._upload_featured_media")
+    @patch("backend.app.wordpress._wp_request")
+    def test_publish_skips_category_when_slug_is_missing_in_wordpress(self, mock_wp_request, mock_upload_media) -> None:
+        def _fake_wp_request(**kwargs):
+            endpoint = kwargs.get("endpoint", "")
+            if kwargs.get("method") == "GET" and endpoint.startswith("categories?slug="):
+                return []
+            if kwargs.get("method") == "POST" and endpoint == "posts":
+                return {"id": 903, "link": "https://example.org/?p=903"}
+            return {}
+
+        mock_wp_request.side_effect = _fake_wp_request
+        article = {
+            "title": "Dometic CFX5 45 im Test: Top-Kühlbox für unterwegs",
+            "content_raw": "Inhalt",
+            "source_url": "https://example.com/source",
+            "canonical_url": "https://example.com/source",
+            "meta_json": '{"generated_tags":[]}',
+        }
+        publish_article_draft(article)
+        payload = [c for c in mock_wp_request.call_args_list if c.kwargs.get("endpoint") == "posts"][0].kwargs["payload"]
+        self.assertNotIn("categories", payload)
+
 
 if __name__ == "__main__":
     unittest.main()