turn "match_release_fuzzy" into a class

Goal of this refactoring was to make the matching process a bit more
configurable by using a class and a cascade of queries.

For a limited test set: `FuzzyReleaseMatcher.match` is works the same as
`match_release_fuzzy`.

23 files changed, 1371 insertions, 111 deletions

diff --git a/TODO.md b/TODO.md
index 5666bc0..9241b60 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,28 +1,32 @@
 # TODO
 
 * [ ] clustering should be broken up, e.g. into "map" and "sort"
+* [ ] match release fuzzy should work not just with title
+* [ ] match container name functions (maybe also with abbreviations, etc)
+* [ ] better documentation, more examples
+* [ ] shiv based packaging
+* [ ] author similarity should be broken up; easier to tweak
+* [ ] split up `verify`
+* [ ] configurable `verify`
+
+Other repos:
 
-In
-[refcat/skate](https://gitlab.com/internetarchive/refcat/-/tree/master/skate)
-we have one simple operation: extract a list of fields from blob of bytes. We
-use [16
-mappers](https://gitlab.com/internetarchive/refcat/-/blob/f33e586d11f5f575f71ad209608ac9ba74fad2e5/skate/cmd/skate-map/main.go#L70-86)
-currently, they are easy to write.
+* [refcat/skate](https://gitlab.com/internetarchive/refcat/-/tree/master/skate)
+
+In refcat we have one simple operation: extract a list of fields from blob of
+bytes. We use [16 mappers](https://is.gd/E0NEXj) currently, they are easy to
+write.
 
 In refcat, we use GNU sort, and just when we need it, e.g.
-[skate-map](https://gitlab.com/internetarchive/refcat/-/blob/f33e586d11f5f575f71ad209608ac9ba74fad2e5/python/refcat/tasks.py#L531-534).
+[skate-map](https://is.gd/Kt9hvL).
 
 The `Cluster` class bundles, iteration, key extraction, sorting and group by
 operation into a single entity.
 
 Also in refcat, we do not work on a single file with clusters any more, but
-mostly with two sorted streams, which are iterated over "comm" style. This
-spares us an extra step of generating the cluster documents, but requires an
-extra component, that allows to plug in various "reduce" functions. In refcat,
-this component is called "zipkey", which is support batching, too.
+mostly with two sorted streams, which are iterated over "mergesort/comm" style.
 
-* [ ] match release fuzzy should work not just with title
-* [ ] match container name functions (maybe also with abbreviations, etc)
-* [ ] better documentation, more examples
-* [ ] shiv based packaging
+This spares us an extra step of generating the cluster documents, but requires
+an extra component, that allows to plug in various "reduce" functions. In
+refcat, this component is called "zipkey", which is support batching, too.
 
diff --git a/fuzzycat/contrib.py b/fuzzycat/contrib.py
new file mode 100644
index 0000000..93753ab
--- /dev/null
+++ b/fuzzycat/contrib.py
@@ -0,0 +1,453 @@
+"""
+Contrib related comparisons.
+
+Example: NgramContribMatcher, which compares two normalized raw name tokens
+with a jaccard index.
+
+    matcher = ContribMatcher(cmp=JaccardIndexThreshold(0.5),
+                             pipeline=Pipeline([
+                                 lambda rc: rc.raw_name,
+                                 str.strip,
+                                 str.lower,
+                                 Ngram(n=3),
+                                 set,
+                             ]))
+    result = matcher.compare(a, b)
+    ...
+
+Some notes from the dataset.
+
+* 692,893,828 contribs
+*  64,680,311 uniq
+
+Top contrib names, many have their name on datasets, which explains the high
+number.
+
+3069752 Kessy Abarenkov
+2383819 Leho Tedersoo
+2383748 Karl-Henrik Larsson
+2383745 Urmas Kõljalg
+2383699 Mohammad Bahram
+2383692 Martin Ryberg
+2382832 R. Henrik Nilsson
+1702455 Markus Döring
+1702427 Tom May
+1702415 Dmitry Schigel
+1702391 Santiago Sánchez-Ramírez
+ 841475 GLIS Of The ITPGRFA
+ 682144 James Scott
+ 682053 Michael Weiss
+ 681404 Susumu Takamatsu
+ 681388 A. Elizabeth Arnold
+ 681347 Artur Alves
+ 681341 Ellen Larsson
+ 681338 Maarja Öpik
+ 681335 Ursula Eberhardt
+ 681324 Nhu Nguyen
+ 681293 Otto Miettinen
+ 681292 Viacheslav Spirin
+ 681287 Gareth W. Griffith
+ 681283 Bálint Dima
+ 681278 Ursula Peintner
+ 681276 Tuula Niskanen
+ 681276 Olinto Liparini Pereira
+ 681275 Kare Liimatainen
+"""
+
+import collections
+import functools
+import itertools
+import logging
+import operator
+import re
+import string
+from typing import Any, Callable, List, Optional, Set
+
+import jellyfish
+import thefuzz
+from fatcat_openapi_client import ReleaseContrib
+
+logger = logging.getLogger("fuzzycat")
+
+
+class Ngram:
+    """
+    Turn a string into a list of overlapping tokens.
+    """
+    def __init__(self, n: int = 3):
+        if n < 1:
+            raise ValueError("positive n required")
+        self.n = n
+
+    def __call__(self, s: str) -> List[str]:
+        if 0 < len(s) < self.n:
+            return [s]
+        return [s[i:i + self.n] for i in range(len(s) - self.n + 1)]
+
+
+class JaccardIndexThreshold:
+    """
+    A Jaccard index threshold that can be used to compare two sets. Two empty
+    sets are equal.
+    """
+    def __init__(self, threshold: float = 0.5, verbose=False):
+        self.threshold = threshold
+        self.verbose = verbose
+
+    def __call__(self, a: Set, b: Set) -> bool:
+        if len(a) == 0 and len(b) == 0:
+            return True
+        index = len(a & b) / len(a | b)
+        if self.verbose:
+            logger.debug("[jaccard] {}".format(index))
+        return index >= self.threshold
+
+
+class FuzzyStringSimilarity:
+    """
+    For two sets of strings, run fuzzy matching with "thefuzz" -
+    https://github.com/seatgeek/thefuzz, which among other things uses
+    Levenshtein distance.
+
+    The min ratio can range from 0 to 100 (with 100 allowing exact matches
+    only).
+    """
+    def __init__(self, min_ratio=75):
+        self.min_ratio = min_ratio
+
+    def __call__(self, a: Set, b: Set) -> bool:
+        agg = 0
+        for v in a:
+            match, score = thefuzz.exctractOne(v, b)
+            agg += score
+        return score > self.min_ratio
+
+
+class Pipeline:
+    """
+    A list of functions to execute, f -> g -> h, etc. Note that the output
+    type of f needs to match the input type of g, etc.
+    """
+    def __init__(self, pipeline: Optional[List[Any]] = None, verbose: bool = False):
+        self.verbose = verbose
+        if pipeline is None:
+            self.pipeline = [
+                lambda v: v,
+            ]
+        else:
+            self.pipeline = pipeline
+
+    def run(self, value: Any) -> Any:
+        v = value
+        for i, f in enumerate(self.pipeline, start=1):
+            v = f(v)
+            if self.verbose:
+                logger.debug("[{}/{}] {}".format(i, len(self.pipeline), v))
+        return v
+
+    def __call__(self, value: Any, verbose: bool = False) -> Any:
+        self.verbose = verbose
+        return self.run(value)
+
+
+# default_release_contrib_pipeline normalizes the raw name.
+default_release_contrib_pipeline = Pipeline([
+    lambda rc: rc.raw_name,
+    str.strip,
+    str.lower,
+])
+
+# default_release_contrib_list_pipeline turns contribs list into a contrib set.
+default_release_contrib_list_pipeline = Pipeline([
+    lambda seq: set((c.raw_name for c in seq)),
+])
+
+
+class ContribMatcher:
+    """
+    Compare two contrib entities and determine a match status, based on some
+    configuration. The final values of the `pipeline` will be compared with
+    `cmp`, which by default is equality.
+
+    Other `cmp` options may generate ngrams and use jaccard index with some
+    threshold or decide on a string similarity metric.
+
+    This is essentially just a shell, the various comparison methods live in
+    the tuple (pipeline, cmp).
+    """
+    def __init__(self,
+                 pipeline: Optional[List[Any]] = default_release_contrib_list_pipeline,
+                 cmp: Callable[[Any, Any], bool] = operator.__eq__):
+        self.pipeline = pipeline
+        self.cmp = cmp
+
+    def compare(self, a: ReleaseContrib, b: ReleaseContrib) -> bool:
+        """
+        Compare returns True, if a and b are considered the same, given a
+        transformation pipeline and a comparison operation.
+        """
+        u = self.pipeline(a)
+        v = self.pipeline(b)
+        return self.cmp(u, v)
+
+
+class ContribListMatcher:
+    """
+    Compare two lists of contribs. Each contrib entry is passed through the
+    same pipeline.
+
+    Often two issues (separate or combined).
+
+    - contrib missing, e.g.
+    - "Gentle Sunder Shrestha", "Gentle S Shrestha", "S. Shrestha", "Gentle Shrestha", ...
+    """
+    def __init__(self,
+                 pipeline: Optional[List[Any]] = default_release_contrib_list_pipeline,
+                 cmp: Callable[[Any, Any], bool] = JaccardIndexThreshold(1.0)):
+        self.pipeline = pipeline
+        self.cmp = cmp
+
+    def compare(self,
+                a: List[ReleaseContrib],
+                b: List[ReleaseContrib],
+                verbose: bool = False) -> bool:
+        """
+        Compare two lists of contribs, pass each one through the pipeline. The
+        result may be a list or any other type. The comparison function needs
+        to be compatible.
+        """
+        u = self.pipeline(a, verbose=verbose)
+        v = self.pipeline(b, verbose=verbose)
+        return self.cmp(u, v)
+
+
+def cleanup_single_ws(s: str) -> str:
+    return re.sub(r"[ ]{2,}", " ", s)
+
+
+def cleanup_remove_ws(s: str) -> str:
+    return re.sub(r"[\n\r\t\s]*", '', s)
+
+
+def cleanup_keep_letters_digits_ws(s: str) -> str:
+    return ''.join((c for c in s if c in string.ascii_letters + string.digits + " "))
+
+
+def test_cleanup_single_ws():
+    Case = collections.namedtuple("Case", "s result")
+    cases = (
+        Case("", ""),
+        Case("abc", "abc"),
+        Case("abc abc", "abc abc"),
+        Case("abc  abc", "abc abc"),
+        Case("   abc  abc", " abc abc"),
+        Case("   abc  abc", " abc abc"),
+    )
+    for c in cases:
+        assert c.result == cleanup_single_ws(c.s)
+
+
+def test_cleanup_remove_ws():
+    Case = collections.namedtuple("Case", "s result")
+    cases = (
+        Case("", ""),
+        Case("abc", "abc"),
+        Case("abc abc", "abcabc"),
+        Case("abc  abc", "abcabc"),
+        Case("   abc  abc", "abcabc"),
+    )
+    for c in cases:
+        assert c.result == cleanup_remove_ws(c.s), c
+
+
+def test_ngram():
+    Case = collections.namedtuple("Case", "s n result")
+    cases = (
+        Case("", 1, []),
+        Case("", 2, []),
+        Case("a", 2, ["a"]),
+        Case("ab", 2, ["ab"]),
+        Case("abcdef", 2, ['ab', 'bc', 'cd', 'de', 'ef']),
+        Case("abcdef", 4, ['abcd', 'bcde', 'cdef']),
+        Case("Nina Rogo", 3, ["Nin", "ina", "na ", "a R", " Ro", "Rog", "ogo"]),
+    )
+    for c in cases:
+        ngram = Ngram(n=c.n)
+        assert ngram(c.s) == c.result
+
+
+def test_pipeline():
+    Case = collections.namedtuple("Case", "pipeline input result")
+    cases = (Case(Pipeline([lambda v: v["a"], str.strip, str.lower,
+                            Ngram(n=3), set]), {"a": " X123  "}, {'123', 'x12'})),
+    for c in cases:
+        result = c.pipeline(c.input)
+        assert result == c.result
+
+
+def test_jaccard_index_threshold():
+    Case = collections.namedtuple("Case", "a b threshold result")
+    cases = (
+        Case(set(), set(), 1.0, True),
+        Case(set(), set(["a"]), 1.0, False),
+        Case(set(["a"]), set(["a"]), 1.0, True),
+        Case(set(["a"]), set(["a", "b"]), 1.0, False),
+        Case(set(["a"]), set(["a", "b"]), 0.5, True),
+        Case(set(["a"]), set(["a", "b", "c"]), 0.5, False),
+    )
+    for c in cases:
+        jit = JaccardIndexThreshold(threshold=c.threshold)
+        result = jit(c.a, c.b)
+        assert result == c.result
+
+
+def test_ngram_contrib_matcher(caplog):
+    Case = collections.namedtuple("Case", "a b result")
+    cases = (
+        Case(
+            ReleaseContrib(raw_name="Jane Austen"),
+            ReleaseContrib(raw_name="J.Austen"),
+            True,
+        ),
+        Case(
+            ReleaseContrib(raw_name="Fjodor Dostojewski"),
+            ReleaseContrib(raw_name="Fyodor Dostoevsky"),
+            False,
+        ),
+        Case(
+            ReleaseContrib(raw_name="Fjodor M. Dostojewski"),
+            ReleaseContrib(raw_name="Fyodor Dostoevsky"),
+            False,
+        ),
+        Case(
+            ReleaseContrib(raw_name="Fjodor Michailowitsch Dostojewski"),
+            ReleaseContrib(raw_name="Fyodor Dostoevsky"),
+            False,
+        ),
+    )
+    matcher = ContribMatcher(cmp=JaccardIndexThreshold(0.4, verbose=True),
+                             pipeline=Pipeline([
+                                 lambda rc: rc.raw_name,
+                                 str.strip,
+                                 str.lower,
+                                 cleanup_remove_ws,
+                                 cleanup_keep_letters_digits_ws,
+                                 Ngram(n=3),
+                                 set,
+                             ],
+                                               verbose=True))
+    for c in cases:
+        with caplog.at_level(logging.DEBUG):
+            result = matcher.compare(c.a, c.b)
+            assert result == c.result
+
+
+def test_jellyfish_soundex_contrib_matcher(caplog):
+    Case = collections.namedtuple("Case", "a b result")
+    cases = (
+        Case(
+            ReleaseContrib(raw_name="Jane Austen"),
+            ReleaseContrib(raw_name="J.Austen"),
+            True,
+        ),
+        Case(
+            ReleaseContrib(raw_name="Fjodor Dostojewski"),
+            ReleaseContrib(raw_name="Fyodor Dostoevsky"),
+            False,
+        ),
+        Case(
+            ReleaseContrib(raw_name="Fjodor M. Dostojewski"),
+            ReleaseContrib(raw_name="Fyodor Dostoevsky"),
+            False,
+        ),
+        Case(
+            ReleaseContrib(raw_name="Fjodor Michailowitsch Dostojewski"),
+            ReleaseContrib(raw_name="Fyodor Dostoevsky"),
+            False,
+        ),
+    )
+    matcher = ContribMatcher(cmp=JaccardIndexThreshold(0.3, verbose=True),
+                             pipeline=Pipeline([
+                                 lambda rc: rc.raw_name,
+                                 str.strip,
+                                 str.lower,
+                                 functools.partial(re.sub, r"[.;]", " "),
+                                 cleanup_keep_letters_digits_ws,
+                                 lambda s: set((jellyfish.soundex(v) for v in s.split())),
+                             ],
+                                               verbose=True))
+    for c in cases:
+        with caplog.at_level(logging.DEBUG):
+            result = matcher.compare(c.a, c.b)
+            assert result == c.result
+
+
+def test_jellyfish_nysiis_contrib_matcher(caplog):
+    Case = collections.namedtuple("Case", "a b result")
+    cases = (
+        Case(
+            ReleaseContrib(raw_name="Jane Austen"),
+            ReleaseContrib(raw_name="J.Austen"),
+            True,
+        ),
+        Case(
+            ReleaseContrib(raw_name="Fjodor Dostojewski"),
+            ReleaseContrib(raw_name="Fyodor Dostoevsky"),
+            False,
+        ),
+        Case(
+            ReleaseContrib(raw_name="Fjodor M. Dostojewski"),
+            ReleaseContrib(raw_name="Fyodor Dostoevsky"),
+            False,
+        ),
+        Case(
+            ReleaseContrib(raw_name="Fjodor Michailowitsch Dostojewski"),
+            ReleaseContrib(raw_name="Fyodor Dostoevsky"),
+            False,
+        ),
+    )
+    matcher = ContribMatcher(cmp=JaccardIndexThreshold(0.3, verbose=True),
+                             pipeline=Pipeline([
+                                 lambda rc: rc.raw_name,
+                                 str.strip,
+                                 str.lower,
+                                 functools.partial(re.sub, r"[.;]", " "),
+                                 cleanup_keep_letters_digits_ws,
+                                 lambda s: set((jellyfish.nysiis(v) for v in s.split())),
+                             ],
+                                               verbose=True))
+    for c in cases:
+        with caplog.at_level(logging.DEBUG):
+            result = matcher.compare(c.a, c.b)
+            assert result == c.result
+
+
+def test_default_contrib_list_matcher(caplog):
+    Case = collections.namedtuple("Case", "a b result")
+    cases = (
+        Case(
+            [],
+            [],
+            True,
+        ),
+        Case(
+            [ReleaseContrib(raw_name="Michael Jordan")],
+            [ReleaseContrib(raw_name="Michael Jordan")],
+            True,
+        ),
+        Case(
+            [ReleaseContrib(raw_name="Michael Jordan")],
+            [ReleaseContrib(raw_name="michael jordan")],
+            False,
+        ),
+        Case(
+            [ReleaseContrib(raw_name="Amadeu Llebaria")],
+            [ReleaseContrib(raw_name="A. Llebaria")],
+            False,
+        ),
+    )
+    matcher = ContribListMatcher()
+    for c in cases:
+        with caplog.at_level(logging.DEBUG):
+            result = matcher.compare(c.a, c.b, verbose=True)
+            assert result == c.result
diff --git a/fuzzycat/grobid_unstructured.py b/fuzzycat/grobid_unstructured.py
index 7470cd7..1765f42 100644
--- a/fuzzycat/grobid_unstructured.py
+++ b/fuzzycat/grobid_unstructured.py
@@ -15,7 +15,7 @@ from typing import Optional
 
 import requests
 from fatcat_openapi_client import ReleaseContrib, ReleaseEntity, ReleaseExtIds
-from grobid_tei_xml import parse_citation_xml, GrobidBiblio
+from grobid_tei_xml import GrobidBiblio, parse_citation_xml
 
 from fuzzycat.config import settings
 from fuzzycat.utils import clean_doi
diff --git a/fuzzycat/matching.py b/fuzzycat/matching.py
index b358899..1531ac6 100644
--- a/fuzzycat/matching.py
+++ b/fuzzycat/matching.py
@@ -1,22 +1,430 @@
+import logging
 import os
 import re
 import sys
-from typing import List, Optional, Type, Union
+from typing import Any, List, Optional, Type, Union
 
 import elasticsearch
 import elasticsearch_dsl
 import fatcat_openapi_client
 import requests
-from fatcat_openapi_client import ContainerEntity, DefaultApi, ReleaseEntity
+from fatcat_openapi_client import (ContainerEntity, DefaultApi, ReleaseContrib, ReleaseEntity)
 from fatcat_openapi_client.rest import ApiException
 
 from fuzzycat.config import settings
+from fuzzycat.contrib import (ContribListMatcher, FuzzyStringSimilarity, JaccardIndexThreshold,
+                              Pipeline)
 from fuzzycat.entities import entity_from_dict, entity_from_json
 from fuzzycat.utils import es_compat_hits_total
 
 FATCAT_API_URL = settings.get("FATCAT_API_URL", "https://api.fatcat.wiki/v0")
 
 
+class FuzzyReleaseMatcher:
+    """
+    FuzzyReleaseMatcher tries to find similar items to a given release in
+    elasticsearch. Exact matches first, then fuzzy.
+
+    In the best case, elasticsearch would automatically rank the most relevant
+    docs first, even with partial data. We still try to steer the matches by
+    using a query cascade. This is configurable. The last query should be a
+    generic.
+
+    The goal here is to get a set of potential matches; verification has to.
+    happen separately.
+
+    TODO:
+
+    Example case not yet working well ("Stuehrenberg" vs "Stührenberg"):
+
+    >>> result = matcher.match(entity_from_dict({"title": "internet archive",
+                                                 "contribs": [{"raw_name":
+                                                               "Stührenberg"}],
+                                                 "ext_ids": {}},
+                                                ReleaseEntity))
+
+    > Should return: https://fatcat.wiki/release/pu7e7tbctna2foqyyxztfw3ufy,
+    https://fatcat.wiki/release/search?q=St%C3%BChrenberg+internet+archive&generic=1
+    (not returning anything via frontend either)
+
+    Make sure we can switch from function to class:
+
+    * [ ] 5 test cases for both
+
+    """
+    def __init__(self, es="https://search.fatcat.wiki", api=None, index="fatcat_release", size=10):
+        if isinstance(es, str):
+            self.es = elasticsearch.Elasticsearch([es])
+        else:
+            self.es = es if es else elasticsearch.Elasticsearch()
+        self.api = api if api else public_api(FATCAT_API_URL)
+        self.index = index
+        self.size = size
+        self.logger = logging.getLogger("fuzzy")
+
+    def match_release_by_id(self, release, **kwargs) -> List[ReleaseEntity]:
+        """
+        Check for exact matches by identifier.
+        """
+        ext_ids = release.ext_ids
+        attrs = (
+            "doi",
+            "pmid",
+            "wikidata_qid",
+            "core",
+            "pmcid",
+            "arxiv",
+            "dblp",
+            "doaj",
+            "jstor",
+            "isbn13",
+            "ark",
+            "mag",
+            "oai",
+        )
+        for attr in attrs:
+            value = getattr(ext_ids, attr)
+            if not value:
+                continue
+            try:
+                r = self.api.lookup_release(**{attr: value})
+            except fatcat_openapi_client.rest.ApiException as err:
+                if err.status in [404, 400]:
+                    r = None
+                else:
+                    raise err
+            if r:
+                return [r]
+        return []
+
+    def match_release_exact_title_exact_contrib(self, release):
+        """
+        Match exact title and exact contrib names. Case insensitive, order of
+        contribs does not matter.
+        """
+        if release.title is None or release.contribs is None:
+            return []
+        contrib_queries = [{
+            "match": {
+                "contrib_names": {
+                    "query": contrib.raw_name,
+                    "operator": "AND",
+                }
+            }
+        } for contrib in release.contribs]
+        query = {
+            "bool": {
+                "must": [{
+                    "match": {
+                        "title": {
+                            "query": release.title,
+                            "operator": "AND",
+                        },
+                    }
+                }] + contrib_queries,
+            },
+        }
+        result = []
+
+        resp = self.es.search(query=query, size=self.size, track_total_hits=True, index=self.index)
+        hits_total = es_compat_hits_total(resp)
+        if hits_total == 0:
+            return result
+        if hits_total > self.size:
+            self.logger.warn('more than {} hits: {}'.format(self.size, hits_total))
+
+        entities = response_to_entity_list(resp,
+                                           entity_type=ReleaseEntity,
+                                           size=self.size,
+                                           api=self.api)
+
+        # Require overlap of contrib.
+        matcher = ContribListMatcher(
+            cmp=JaccardIndexThreshold(1.0),
+            pipeline=Pipeline([
+                lambda contribs: set((c.raw_name.strip().lower() for c in contribs)),
+            ]),
+        )
+
+        for re in entities:
+            if re.title.strip().lower() != release.title.strip().lower():
+                continue
+            if not matcher.compare(re.contribs, release.contribs):
+                continue
+            result.append(re)
+        return result
+
+    def match_release_exact_title_partial_contrib(self, release):
+        """
+        Allow for exact authors, but ok, if some are missing.
+        """
+        if release.title is None or release.contribs is None:
+            return []
+        contrib_queries = [{
+            "match": {
+                "contrib_names": {
+                    "query": contrib.raw_name,
+                    "operator": "AND",
+                }
+            }
+        } for contrib in release.contribs]
+        query = {
+            "bool": {
+                "must": [{
+                    "match": {
+                        "title": {
+                            "query": release.title,
+                            "operator": "AND",
+                        },
+                    }
+                }] + contrib_queries,
+            },
+        }
+        result = []
+        resp = self.es.search(query=query, size=self.size, track_total_hits=True, index=self.index)
+        if es_compat_hits_total(resp) == 0:
+            return result
+        if es_compat_hits_total(resp) > self.size:
+            raise NotImplementedError('result set too large: {}'.format(es))
+        entities = response_to_entity_list(resp,
+                                           entity_type=ReleaseEntity,
+                                           size=self.size,
+                                           api=self.api)
+
+        # Require at least half the contribs to be shared.
+        matcher = ContribListMatcher(
+            cmp=JaccardIndexThreshold(0.5),
+            pipeline=Pipeline([
+                lambda contribs: set((c.raw_name.strip().lower() for c in contribs)),
+            ]),
+        )
+
+        for re in entities:
+            if re.title.strip().lower() != release.title.strip().lower():
+                continue
+            if not matcher.compare(re.contribs, release.contribs):
+                continue
+            result.append(re)
+        return result
+
+    def match_release_exact_title_fuzzy_contrib(self, release):
+        """
+        Exact title but ok it authors differ (slightly).
+        """
+        if release.title is None or release.contribs is None:
+            return []
+        contrib_tokens = [tok for c in release.contribs for tok in c.raw_name.split()]
+        contrib_queries = [{
+            "match": {
+                "contrib_names": {
+                    "query": token,
+                }
+            }
+        } for token in contrib_tokens]
+        query = {
+            "bool": {
+                "must": [{
+                    "match": {
+                        "title": {
+                            "query": release.title,
+                            "operator": "AND",
+                        },
+                    }
+                }] + contrib_queries,
+            },
+        }
+        result = []
+        resp = self.es.search(query=query, size=self.size, track_total_hits=True, index=self.index)
+        if es_compat_hits_total(resp) == 0:
+            return result
+        if es_compat_hits_total(resp) > self.size:
+            raise NotImplementedError('todo: scroll required for larger result sets: {}'.format(es))
+        entities = response_to_entity_list(resp,
+                                           entity_type=ReleaseEntity,
+                                           size=self.size,
+                                           api=self.api)
+
+        matcher = ContribListMatcher(
+            cmp=FuzzyStringSimilarity(min_ratio=60),
+            pipeline=Pipeline([
+                lambda contribs: set((c.raw_name.strip().lower() for c in contribs)),
+            ]),
+        )
+
+        for re in entities:
+            if re.title.strip().lower() != release.title.strip().lower():
+                continue
+            if not matcher.compare(re.contribs, release.contribs):
+                continue
+            result.append(re)
+        return result
+
+    def match_release_exact_title(self, release):
+        """
+        Exact title, but any author. For common titles, this will yield 100s or
+        1000s or results.
+        """
+        if release.title is None:
+            return []
+        query = {
+            "bool": {
+                "must": [{
+                    "match": {
+                        "title": {
+                            "query": release.title,
+                            "operator": "AND",
+                        },
+                    }
+                }],
+            },
+        }
+        result = []
+        resp = self.es.search(query=query, size=self.size, track_total_hits=True, index=self.index)
+        if es_compat_hits_total(resp) == 0:
+            return result
+        if es_compat_hits_total(resp) > self.size:
+            self.logger.warn('too many hits: {}'.format(es_compat_hits_total(resp)))
+        entities = response_to_entity_list(resp,
+                                           entity_type=ReleaseEntity,
+                                           size=self.size,
+                                           api=self.api)
+        for re in entities:
+            if re.title.strip().lower() != release.title.strip().lower():
+                continue
+            result.append(re)
+        return result
+
+    def match_release_fuzzy_title_fuzzy_contrib(self, release):
+        """
+        Using elasticsearch fuzziness option (which is not that fuzzy).
+        """
+        if release.title is None or release.contribs is None:
+            return []
+        contrib_tokens = [tok for c in release.contribs for tok in c.raw_name.split()]
+        contrib_queries = [{
+            "match": {
+                "contrib_names": {
+                    "query": token,
+                }
+            }
+        } for token in contrib_tokens]
+        query = {
+            "bool": {
+                "must": [
+                    {
+                        "match": {
+                            "title": {
+                                "query": release.title,
+                                "operator": "AND",
+                                "fuzziness": "AUTO",
+                            },
+                        }
+                    },
+                ] + contrib_queries,
+            },
+        }
+        result = []
+        resp = self.es.search(query=query, size=self.size, track_total_hits=True, index=self.index)
+        if es_compat_hits_total(resp) == 0:
+            return result
+        if es_compat_hits_total(resp) > self.size:
+            raise ValueError('too many hits: {}'.format(es_compat_hits_total(resp)))
+        entities = response_to_entity_list(resp,
+                                           entity_type=ReleaseEntity,
+                                           size=self.size,
+                                           api=self.api)
+        return entities
+
+    def match_release_generic(self, release):
+        """
+        Final catch all variant via title.
+        """
+        if release.title is None:
+            return []
+        query = {
+            "bool": {
+                "must": [
+                    {
+                        "match": {
+                            "title": {
+                                "query": release.title,
+                                "operator": "OR",
+                                "fuzziness": "AUTO",
+                            },
+                        }
+                    },
+                ],
+            },
+        }
+        result = []
+        resp = self.es.search(query=query, size=self.size, track_total_hits=True, index=self.index)
+        if es_compat_hits_total(resp) == 0:
+            return result
+        if es_compat_hits_total(resp) > self.size:
+            self.logger.warn('too many hits: {}'.format(es_compat_hits_total(resp)))
+        entities = response_to_entity_list(resp,
+                                           entity_type=ReleaseEntity,
+                                           size=self.size,
+                                           api=self.api)
+        return entities
+
+    def match_release_generic_fuzzy_contrib(self, release):
+        """
+        Only match contribs, if they exist.
+        """
+        if release.contribs is None:
+            return []
+        contrib_tokens = [tok for c in release.contribs for tok in c.raw_name.split()]
+        contrib_queries = [{
+            "match": {
+                "contrib_names": {
+                    "query": token,
+                }
+            }
+        } for token in contrib_tokens]
+        query = {
+            "bool": {
+                "must": contrib_queries,
+            },
+        }
+        result = []
+        resp = self.es.search(query=query, size=self.size, track_total_hits=True, index=self.index)
+        if es_compat_hits_total(resp) == 0:
+            return result
+        if es_compat_hits_total(resp) > self.size:
+            self.logger.warn('too many hits: {}'.format(es_compat_hits_total(resp)))
+        entities = response_to_entity_list(resp,
+                                           entity_type=ReleaseEntity,
+                                           size=self.size,
+                                           api=self.api)
+        return entities
+
+    def match_cascade(self, release, *qs, **kwargs):
+        """
+        Returns the result from the first query that returns a result. All query
+        functions need to be defined on this class (for now).
+        """
+        for q in qs:
+            self.logger.debug("[cascade] {}".format(q))
+            result = q(release, **kwargs)
+            if len(result) > 0:
+                return result
+        return []
+
+    def match(self, release: Optional[ReleaseEntity]) -> List[ReleaseEntity]:
+        """
+        Match returns a list of match candidates given a release entity.
+        """
+        if not release:
+            return []
+        return self.match_cascade(
+            release, self.match_release_by_id, self.match_release_exact_title_exact_contrib,
+            self.match_release_exact_title_partial_contrib,
+            self.match_release_exact_title_fuzzy_contrib, self.match_release_exact_title,
+            self.match_release_fuzzy_title_fuzzy_contrib, self.match_release_generic,
+            self.match_release_generic_fuzzy_contrib)
+
+
 def match_release_fuzzy(
     release: ReleaseEntity,
     size: int = 5,
@@ -28,6 +436,8 @@ def match_release_fuzzy(
     fatcat using Elasticsearch.
 
     TODO: rename "es" parameter to "es_client", which would be clearer
+
+    This is deprecated, move to matcher class.
     """
     assert isinstance(release, ReleaseEntity)
 
@@ -41,6 +451,17 @@ def match_release_fuzzy(
     if api is None:
         api = public_api(FATCAT_API_URL)
 
+    # > query cascade
+    #
+    # [x] 1 exact ids
+    # [ ] 2 exact title and exact contrib
+    # [ ] 3 exact title and fuzzy contrib
+    # [ ] 4 exact title
+    # [ ] 5 title w/o stopwords, fuzzy contrib
+    # [ ] 6 title w/o stopwords
+    # [ ] 7 fuzzy title and fuzzy contrib
+    # [ ] 8 fuzzy whole document
+
     # Try to match by external identifier.
     # TODO: use api, ability to disable; benchmark
     ext_ids = release.ext_ids
@@ -75,105 +496,89 @@ def match_release_fuzzy(
 
     if release.title is not None and release.contribs is not None:
         names = " ".join([c.raw_name for c in release.contribs])
-        body = {
-            "track_total_hits": True,
-            "query": {
-                "bool": {
-                    "must": [
-                        {
-                            "match": {
-                                "title": {
-                                    "query": release.title,
-                                    "operator": "AND",
-                                    "fuzziness": "AUTO",
-                                },
-                            }
-                        },
-                        {
-                            "match": {
-                                "contrib_names": {
-                                    "query": names,
-                                    "operator": "AND",
-                                    "fuzziness": "AUTO",
-                                }
+        query = {
+            "bool": {
+                "must": [
+                    {
+                        "match": {
+                            "title": {
+                                "query": release.title,
+                                "operator": "AND",
+                                "fuzziness": "AUTO",
+                            },
+                        }
+                    },
+                    {
+                        "match": {
+                            "contrib_names": {
+                                "query": names,
+                                "operator": "AND",
+                                "fuzziness": "AUTO",
                             }
-                        },
-                    ],
-                },
+                        }
+                    },
+                ],
             },
-            "size": size,
         }
-        resp = es.search(body=body, index="fatcat_release")
+        resp = es.search(query=query, index="fatcat_release", size=size, track_total_hits=True)
         if es_compat_hits_total(resp) > 0:
             return response_to_entity_list(resp, entity_type=ReleaseEntity, size=size, api=api)
 
-        body = {
-            "track_total_hits": True,
-            "query": {
-                "bool": {
-                    "should": [
-                        {
-                            "match": {
-                                "title": {
-                                    "query": release.title,
-                                    "operator": "AND",
-                                    "fuzziness": "AUTO",
-                                },
+        query = {
+            "bool": {
+                "should": [
+                    {
+                        "match": {
+                            "title": {
+                                "query": release.title,
+                                "operator": "AND",
+                                "fuzziness": "AUTO",
+                            },
+                        }
+                    },
+                    {
+                        "match": {
+                            "contrib_names": {
+                                "query": names,
+                                "operator": "AND",
+                                "fuzziness": "AUTO",
                             }
-                        },
-                        {
-                            "match": {
-                                "contrib_names": {
-                                    "query": names,
-                                    "operator": "AND",
-                                    "fuzziness": "AUTO",
-                                }
-                            }
-                        },
-                    ],
-                },
+                        }
+                    },
+                ],
             },
-            "size": size,
         }
-        resp = es.search(body=body, index="fatcat_release")
+        resp = es.search(query=query, index="fatcat_release", size=size, track_total_hits=True)
         if es_compat_hits_total(resp) > 0:
             return response_to_entity_list(resp, entity_type=ReleaseEntity, size=size, api=api)
 
     # Note: If the title is short, we will get lots of results here; do we need
     # to check for title length or result set length length or result set
     # length here?
-    body = {
-        "track_total_hits": True,
-        "query": {
-            "match": {
-                "title": {
-                    "query": release.title,
-                    "operator": "AND",
-                }
+    query = {
+        "match": {
+            "title": {
+                "query": release.title,
+                "operator": "AND",
             }
-        },
-        "size": size,
+        }
     }
-    resp = es.search(body=body, index="fatcat_release")
+    resp = es.search(query=query, index="fatcat_release", size=size, track_total_hits=True)
     if es_compat_hits_total(resp) > 0:
         return response_to_entity_list(resp, entity_type=ReleaseEntity, size=size, api=api)
 
     # Get fuzzy.
     # https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#fuzziness
-    body = {
-        "track_total_hits": True,
-        "query": {
-            "match": {
-                "title": {
-                    "query": release.title,
-                    "operator": "AND",
-                    "fuzziness": "AUTO",
-                }
+    query = {
+        "match": {
+            "title": {
+                "query": release.title,
+                "operator": "AND",
+                "fuzziness": "AUTO",
             }
-        },
-        "size": size,
+        }
     }
-    resp = es.search(body=body, index="fatcat_release")
+    resp = es.search(query=query, index="fatcat_release", size=size, track_total_hits=True)
     if es_compat_hits_total(resp) > 0:
         return response_to_entity_list(resp, entity_type=ReleaseEntity, size=size, api=api)
 
diff --git a/fuzzycat/sandcrawler.py b/fuzzycat/sandcrawler.py
index 958756a..63b85e6 100644
--- a/fuzzycat/sandcrawler.py
+++ b/fuzzycat/sandcrawler.py
@@ -1,6 +1,7 @@
-import regex
 import unicodedata
 
+import regex
+
 # from http://zderadicka.eu/removing-diacritics-marks-from-strings/
 SANDCRAWLER_CHAR_MAP = {
     '\N{Latin capital letter AE}': 'AE',
@@ -63,6 +64,7 @@ SANDCRAWLER_REMOVE_CHAR_REGEX = regex.compile(
     r"[\s\p{Punctuation}\p{M}\p{InCombiningDiacriticalMarks}\u2000-\u206F\u2E00-\u2E7F’·“”‘’“”«»「」¿–±§_`°ʖ©®¤=<>|+$^~≈√∫≤≥÷ƒ∆¬£¢∞¥◊€]"
 )
 
+
 def sandcrawler_slugify(raw: str) -> str:
     """
     Python re-implementation of sandcrawler Scala code for string comparison
@@ -155,4 +157,3 @@ def test_sandcrawler_slugify() -> None:
                 print(unicodedata.name(c))
             print(in_str)
         assert sandcrawler_slugify(in_str) == out_str
-
diff --git a/fuzzycat/verify.py b/fuzzycat/verify.py
index 9eb808b..f570511 100644
--- a/fuzzycat/verify.py
+++ b/fuzzycat/verify.py
@@ -233,10 +233,9 @@ def verify(a: Dict, b: Dict, min_title_length=5) -> Tuple[str, str]:
         if has_doi_prefix(a_doi, "10.3403") and has_doi_prefix(b_doi, "10.3403"):
             if a_doi + "u" == b_doi or b_doi + "u" == a_doi:
                 return Verify(Status.STRONG, Reason.CUSTOM_BSI_UNDATED)
-            if a_title == b_title and ((dict_has_key(a, "extra.subtitle")
-                                        and not dict_has_key(b, "extra.subtitle")) or
-                                       (dict_has_key(b, "extra.subtitle")
-                                        and not dict_has_key(a, "extra.subtitle"))):
+            if a_title == b_title and (
+                (dict_has_key(a, "extra.subtitle") and not dict_has_key(b, "extra.subtitle")) or
+                (dict_has_key(b, "extra.subtitle") and not dict_has_key(a, "extra.subtitle"))):
                 return Verify(Status.STRONG, Reason.CUSTOM_BSI_SUBDOC)
     except PathAccessError:
         pass
diff --git a/notes/2021_11_fuzzycat_refactoring.md b/notes/2021_11_fuzzycat_refactoring.md
new file mode 100644
index 0000000..171cee3
--- /dev/null
+++ b/notes/2021_11_fuzzycat_refactoring.md
@@ -0,0 +1,87 @@
+# Proposal: Fuzzycat Refactoring
+
+* Goal: Refactor fuzzycat to make matching and verification more composable,
+  configurable and testable.
+* Status: wip
+
+A better design.
+
+* it has a correct scope (e.g. match X; very Y)
+* it has good defaults, but allows configuration
+* it is clear how and where to extend functionality
+* it is easy to add one new test for a case
+
+## Matching
+
+* fuzzy matching will be a cascade of queries, until a result is returned
+* there is an order of queries from exact to very fuzzy
+* alternatively, we could use "ensemble matching", that takes the intersection of a couple of queries
+* ES queries cannot cover all cases, we need to add additional checks; e.g. author list comparison
+
+Example
+
+    FuzzyReleaseMatcher
+        match_release_id
+        match_release_exact_title_exact_contrib
+        match_release_...
+
+        match_release_fuzzy (runs a cascade of queries)
+
+Each function is testable on its own. The class keeps the es client and other
+global config around. It's scope is clear: given a "release" (or maybe just a
+title string), generate a list of potentially related releases.
+
+Other entities follow the same pattern.
+
+    FuzzyContainerMatcher
+        match_container_id
+        match_container_issn
+        match_container_abbreviation
+        match_container_...
+
+        match_container_fuzzy (runs a cascade of queries)
+
+A helper object (not exactly the entity) for matching list of authors. Allows
+to match by various means, e.g. exact, short names, partial lists, etc. Should
+account for case, order, etc.
+
+    FuzzyContribsMatcher
+        match_exact
+        match_short_names
+        match_partial_list
+
+        match_fuzzy
+
+For each method in each matcher class, we can construct a test case only for
+one particular method. A new method can be added with easy and tested separately.
+
+Don't know how yet, but we can create some "profiles" that allow for a matching
+by a set of methods. Or use good defaults on the higher level `_fuzzy(...)` method.
+
+NOTE: the matcher classes could use the verification code internally; generate
+a list of matches with an es query, then use a configured verifier to generate
+verified matches; only put comparison code into verification module.
+
+## Verification (comparison)
+
+Verification works similarly. For each entity we define a set of methods, verifying a specific aspect.
+
+    FuzzyReleaseVerifier
+        verify_release_id
+        verify_release_ext_id
+        verify_release_title_exact_match
+        verify_release_title_contrib_exact_match
+        verify_release_...
+
+        verify(a, b) -> (Status, Reason)
+
+A large number of test cases are already there, may need a bit better structure
+to relate cases to methods. The class can hold global configuration, maybe some
+cached computed properties, if that helps.
+
+
+    FuzzyContainerVerifier
+        verify_container_id
+        ...
+
+
diff --git a/tests/files/README.md b/tests/files/README.md
new file mode 100644
index 0000000..ef674d6
--- /dev/null
+++ b/tests/files/README.md
@@ -0,0 +1,5 @@
+# Matcher Test Files
+
+The goal here is to have a mostly language-independent test cases for matching.
+
+Each subdirectory corresponds to a test function and contains examples for it.
diff --git a/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/0.yaml b/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/0.yaml
new file mode 100644
index 0000000..2df8d9a
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/0.yaml
@@ -0,0 +1,13 @@
+title: titles are case insensitive
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Michael Adams"
+      }
+    ],
+    "title": "digital libraries",
+    "ext_ids": {}
+  }
+expected: 2
diff --git a/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/1.yaml b/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/1.yaml
new file mode 100644
index 0000000..1070408
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/1.yaml
@@ -0,0 +1,13 @@
+title: another vanilla query
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Poul-Henning Kamp"
+      }
+    ],
+    "title": "The hyperdimensional tar pit",
+    "ext_ids": {}
+  }
+expected: 2
diff --git a/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/2.yaml b/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/2.yaml
new file mode 100644
index 0000000..882e746
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/2.yaml
@@ -0,0 +1,16 @@
+title: order of contribs does not matter
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Maurice Florence"
+      },
+      {
+        "raw_name": "Tuomo Tiisala"
+      }
+    ],
+    "title": "Foucault",
+    "ext_ids": {}
+  }
+expected: 1
diff --git a/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/3.yaml b/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/3.yaml
new file mode 100644
index 0000000..0a2ad12
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/3.yaml
@@ -0,0 +1,16 @@
+title: order of contribs does not matter
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Tuomo Tiisala"
+      },
+      {
+        "raw_name": "Maurice Florence"
+      }
+    ],
+    "title": "Foucault",
+    "ext_ids": {}
+  }
+expected: 1
diff --git a/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/4.yaml b/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/4.yaml
new file mode 100644
index 0000000..36ea0fe
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_exact_contrib/4.yaml
@@ -0,0 +1,16 @@
+title: short version of name should not work
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Tuomo Tiisala"
+      },
+      {
+        "raw_name": "M. Florence"
+      }
+    ],
+    "title": "Foucault",
+    "ext_ids": {}
+  }
+expected: 0
diff --git a/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/0.yaml b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/0.yaml
new file mode 100644
index 0000000..07230e8
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/0.yaml
@@ -0,0 +1,14 @@
+title: titles are case insensitive
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Michael Adams"
+      }
+    ],
+    "title": "digital libraries",
+    "ext_ids": {}
+  }
+jaccard_index_threshold: 1.0
+expected: 2
diff --git a/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/1.yaml b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/1.yaml
new file mode 100644
index 0000000..62e9586
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/1.yaml
@@ -0,0 +1,14 @@
+title: another vanilla query
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Poul-Henning Kamp"
+      }
+    ],
+    "title": "The hyperdimensional tar pit",
+    "ext_ids": {}
+  }
+jaccard_index_threshold: 1.0
+expected: 2
diff --git a/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/2.yaml b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/2.yaml
new file mode 100644
index 0000000..b89e825
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/2.yaml
@@ -0,0 +1,17 @@
+title: order of contribs does not matter
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Maurice Florence"
+      },
+      {
+        "raw_name": "Tuomo Tiisala"
+      }
+    ],
+    "title": "Foucault",
+    "ext_ids": {}
+  }
+jaccard_index_threshold: 1.0
+expected: 1
diff --git a/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/3.yaml b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/3.yaml
new file mode 100644
index 0000000..3de7262
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/3.yaml
@@ -0,0 +1,17 @@
+title: order of contribs does not matter
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Tuomo Tiisala"
+      },
+      {
+        "raw_name": "Maurice Florence"
+      }
+    ],
+    "title": "Foucault",
+    "ext_ids": {}
+  }
+jaccard_index_threshold: 1.0
+expected: 1
diff --git a/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/4.yaml b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/4.yaml
new file mode 100644
index 0000000..39fb065
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/4.yaml
@@ -0,0 +1,17 @@
+title: short version of name should not work
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Tuomo Tiisala"
+      },
+      {
+        "raw_name": "M. Florence"
+      }
+    ],
+    "title": "Foucault",
+    "ext_ids": {}
+  }
+jaccard_index_threshold: 1.0
+expected: 0
diff --git a/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/5.yaml b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/5.yaml
new file mode 100644
index 0000000..fff19fa
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/5.yaml
@@ -0,0 +1,17 @@
+title: here, Iz Beltagy is missing from author, but still retrieved
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Arman Cohan"
+      },
+      {
+        "raw_name": "Kyle Lo"
+      }
+    ],
+    "title": "SciBERT: A Pretrained Language Model for Scientific Text",
+    "ext_ids": {}
+  }
+jaccard_index_threshold: 0.5
+expected: 3
diff --git a/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/6.yaml b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/6.yaml
new file mode 100644
index 0000000..d4e0025
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/6.yaml
@@ -0,0 +1,14 @@
+title: here, 2/3 authors are missing, we fail with jaccard index 0.5
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Arman Cohan"
+      }
+    ],
+    "title": "SciBERT: A Pretrained Language Model for Scientific Text",
+    "ext_ids": {}
+  }
+jaccard_index_threshold: 0.5
+expected: 0
diff --git a/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/7.yaml b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/7.yaml
new file mode 100644
index 0000000..23d5a8d
--- /dev/null
+++ b/tests/files/fuzzy_release_match_release_exact_title_partial_contrib/7.yaml
@@ -0,0 +1,17 @@
+title: match, despite trailing whitespace
+date: 2021-11-08
+input: >
+  {
+    "contribs": [
+      {
+        "raw_name": "Arman Cohan"
+      },
+      {
+        "raw_name": "Kyle Lo"
+      }
+    ],
+    "title": "SciBERT: A Pretrained Language Model for Scientific Text    ",
+    "ext_ids": {}
+  }
+jaccard_index_threshold: 0.5
+expected: 3
diff --git a/tests/test_grobid_unstructured.py b/tests/test_grobid_unstructured.py
index cf71f91..f36f9a4 100644
--- a/tests/test_grobid_unstructured.py
+++ b/tests/test_grobid_unstructured.py
@@ -18,11 +18,7 @@ def test_grobid_ref_to_release():
                 given_name='ahab',
                 surname='sailor',
             ),
-            GrobidAuthor(
-                full_name='mary jane',
-                given_name='mary',
-                surname='jane'
-            ),
+            GrobidAuthor(full_name='mary jane', given_name='mary', surname='jane'),
         ],
     )
     r = grobid_ref_to_release(d)
diff --git a/tests/test_matching.py b/tests/test_matching.py
index ad971a5..ca94c2a 100644
--- a/tests/test_matching.py
+++ b/tests/test_matching.py
@@ -1,13 +1,14 @@
+import collections
 import logging
 import warnings
 
 import elasticsearch
 import pytest
 import requests
-from fatcat_openapi_client import ReleaseEntity
+from fatcat_openapi_client import ReleaseEntity, ReleaseContrib
 
-from fuzzycat.entities import entity_from_dict
-from fuzzycat.matching import anything_to_entity, match_release_fuzzy
+from fuzzycat.entities import entity_from_dict, entity_from_json
+from fuzzycat.matching import anything_to_entity, match_release_fuzzy, FuzzyReleaseMatcher
 
 warnings.filterwarnings(
     "ignore")  # InsecureRequestWarning: Unverified HTTPS request is being made to host ...
@@ -18,6 +19,9 @@ from fatcat_openapi_client import ReleaseEntity
 import pytest
 import elasticsearch
 import logging
+import yaml
+import glob
+import json
 
 logger = logging.getLogger('test_matching')
 logger.setLevel(logging.DEBUG)
@@ -40,19 +44,35 @@ def is_reachable(url, timeout=3):
         return False
 
 
+def yaml_to_cases(klass,
+                  files="tests/files/fuzzy_release_match_release_exact_title_exact_contrib/*.yaml"):
+    """
+    Turn yaml files into a collection of named tuple test cases. The glob is
+    relative to the project root (i.e. where you usually run `pytest` from).
+    """
+    cases = []
+    for path in glob.glob(files):
+        with open(path) as f:
+            doc = yaml.load(f, Loader=yaml.Loader)
+            cases.append(klass(**doc))
+    return cases
+
+
 @pytest.fixture
 def es_client():
     return elasticsearch.Elasticsearch([FATCAT_SEARCH_URL])
 
 
-@pytest.mark.skipif(
-    is_not_reachable(FATCAT_SEARCH_URL),
-    reason="{} not reachable, use e.g. FUZZYCAT_FATCAT_SEARCH_URL=localhost:9200 to override".
-    format(FATCAT_SEARCH_URL))
+# @pytest.mark.skipif(
+#     is_not_reachable(FATCAT_SEARCH_URL),
+#     reason="{} not reachable, use e.g. FUZZYCAT_FATCAT_SEARCH_URL=localhost:9200 to override".
+#     format(FATCAT_SEARCH_URL))
 def test_match_release_fuzzy(es_client, caplog):
     """
     This test is tied to the current index contents, so if that changes, this
     test may fail as well.
+
+    Note: Deprecated. We want to get rid of this.
     """
     cases = (
         ("wtv64ahbdzgwnan7rllwr3nurm", 1),
@@ -106,3 +126,92 @@ def test_match_release_fuzzy(es_client, caplog):
             logging.info("[{}] given title '{}', found {}, {}".format(i, entity.title, len(result),
                                                                       [v.title for v in result]))
         assert len(result) == count, doc
+
+
+def test_matcher_match_release(es_client, caplog):
+    cases = (
+        ("wtv64ahbdzgwnan7rllwr3nurm", 1),
+        ("eqcgtpav3na5jh56o5vjsvb4ei", 1),
+    )
+    matcher = FuzzyReleaseMatcher(es=es_client, size=5)
+    for i, (ident, count) in enumerate(cases):
+        entity = anything_to_entity(ident, ReleaseEntity)
+        result = matcher.match(entity)
+        logger.info("[{}] given {}, found {}".format(i, entity.title, len(result)))
+        assert len(result) == count
+
+    # Partial data.
+    cases = (
+        ({
+            "title": "digital libraries",
+            "ext_ids": {}
+        }, 5),
+        ({
+            "title": "unlikelytitle",
+            "ext_ids": {}
+        }, 0),
+        ({
+            "title": "Imminent dystopia",
+            "ext_ids": {}
+        }, 5),
+        ({
+            "title": "",
+            "contribs": [{
+                "raw_name": "Aristoteles"
+            }],
+            "ext_ids": {}
+        }, 5),
+        # ({
+        #     "title": "Letter",
+        #     "contribs": [{"raw_name": "Claudel"}],
+        #     "ext_ids": {}
+        # }, 1),
+        # ({
+        #     "title": "The Future of Digital Scholarship",
+        #     "contribs": [{
+        #         "raw_name": "Costantino Thanos"
+        #     }],
+        #     "ext_ids": {}
+        # }, 5),
+    )
+    for i, (doc, count) in enumerate(cases):
+        entity = entity_from_dict(doc, ReleaseEntity)
+        result = matcher.match(entity)
+        with caplog.at_level(logging.INFO):
+            logging.info("[{}] given title '{}', found {}, {}".format(i, entity.title, len(result),
+                                                                      [v.title for v in result]))
+        assert len(result) == count, doc
+
+
+def test_fuzzy_release_matcher_match_release_by_id(es_client, caplog):
+    matcher = FuzzyReleaseMatcher(es=es_client)
+    cases = (
+        ("wtv64ahbdzgwnan7rllwr3nurm", 1),
+        ("eqcgtpav3na5jh56o5vjsvb4ei", 1),
+    )
+    for i, (ident, count) in enumerate(cases):
+        entity = anything_to_entity(ident, ReleaseEntity)
+        result = matcher.match_release_by_id(entity)
+        assert len(result) == count
+
+
+def test_fuzzy_release_match_release_exact_title_exact_contrib(es_client, caplog):
+    matcher = FuzzyReleaseMatcher(es=es_client)
+    Case = collections.namedtuple("Case", "title date input expected")
+    cases = yaml_to_cases(
+        Case, "tests/files/fuzzy_release_match_release_exact_title_exact_contrib/*.yaml")
+    for i, c in enumerate(cases):
+        entity = entity_from_json(c.input, ReleaseEntity)
+        result = matcher.match_release_exact_title_exact_contrib(entity)
+        assert len(result) == c.expected, "[{}] {}".format(c.title, c.input)
+
+
+def test_fuzzy_release_match_release_exact_title_partial_contrib(es_client, caplog):
+    matcher = FuzzyReleaseMatcher(es=es_client)
+    Case = collections.namedtuple("Case", "title date input jaccard_index_threshold expected")
+    cases = yaml_to_cases(
+        Case, "tests/files/fuzzy_release_match_release_exact_title_partial_contrib/*.yaml")
+    for i, c in enumerate(cases):
+        entity = entity_from_json(c.input, ReleaseEntity)
+        result = matcher.match_release_exact_title_partial_contrib(entity)
+        assert len(result) == c.expected, "[{}] {}".format(c.title, c.input)