diff --git a/examples/example-all.yaml.sb b/examples/example-all.yaml.sb
index 3a167565..01a95015 100644
--- a/examples/example-all.yaml.sb
+++ b/examples/example-all.yaml.sb
@@ -1,17 +1,26 @@
-bookoptions: 
-  - "diagram"
-  - "repeatchords"
-  - "lilypond"
-  - "pictures"
-booktype: "chorded"
-datadir: "."
-template: "patacrep.tex"
-lang: "fr"
-encoding: "utf8"
-authwords: 
-  sep: 
+book:
+  lang: fr
+  encoding: utf8
+  template: patacrep.tex
+  datadir: "."
+  pictures: yes
+chords:
+  show: yes
+  diagramreminder: all
+  repeatchords: yes
+
+authors:
+  separators:
     - "and"
     - "et"
-content: 
-  - 
-    - "sorted"
\ No newline at end of file
+content: [["sorted"]]
+
+template:
+  patacrep.tex:
+    color:
+      songlink: FF0000
+      hyperlink: 0000FF
+    bgcolor:
+      note: D1E4AE
+      songnumber: AED1E4
+      index: E4AED1 #not enough songs to see it
\ No newline at end of file
diff --git a/patacrep/Rx.py b/patacrep/Rx.py
new file mode 100644
index 00000000..677a3461
--- /dev/null
+++ b/patacrep/Rx.py
@@ -0,0 +1,566 @@
+# Downloaded from https://github.com/rjbs/rx
+# The contents of the Rx repository are copyright (C) 2008, Ricardo SIGNES.
+# They may be distributed under the terms of the 
+# GNU  Public License (GPL) Version 2, June 1991
+
+#pylint: skip-file
+
+import re
+import types
+from numbers import Number
+
+
+core_types = [ ]
+
+class SchemaError(Exception):
+  pass
+
+class SchemaMismatch(Exception):
+  pass
+
+class SchemaTypeMismatch(SchemaMismatch):
+  def __init__(self, name, desired_type):
+    SchemaMismatch.__init__(self, '{0} must be {1}'.format(name, desired_type))
+
+class SchemaValueMismatch(SchemaMismatch):
+  def __init__(self, name, value):
+    SchemaMismatch.__init__(self, '{0} must equal {1}'.format(name, value))
+
+class SchemaRangeMismatch(SchemaMismatch):
+  pass
+
+def indent(text, level=1, whitespace='  '):
+    return '\n'.join(whitespace*level+line for line in text.split('\n'))
+
+class Util(object):
+  @staticmethod
+  def make_range_check(opt):
+
+    if not {'min', 'max', 'min-ex', 'max-ex'}.issuperset(opt):
+      raise ValueError("illegal argument to make_range_check")
+    if {'min', 'min-ex'}.issubset(opt):
+      raise ValueError("Cannot define both exclusive and inclusive min")
+    if {'max', 'max-ex'}.issubset(opt):
+      raise ValueError("Cannot define both exclusive and inclusive max")      
+
+    r = opt.copy()
+    inf = float('inf')
+
+    def check_range(value):
+      return(
+        r.get('min',    -inf) <= value and \
+        r.get('max',     inf) >= value and \
+        r.get('min-ex', -inf) <  value and \
+        r.get('max-ex',  inf) >  value
+        )
+
+    return check_range
+
+  @staticmethod
+  def make_range_validator(opt):
+    check_range = Util.make_range_check(opt)
+
+    r = opt.copy()
+    nan = float('nan')
+
+    def validate_range(value, name='value'):
+      if not check_range(value):
+        if r.get('min', nan) == r.get('max', nan):
+          msg = '{0} must equal {1}'.format(name, r['min'])
+          raise SchemaRangeMismatch(msg)
+        
+        range_str = ''
+        if 'min' in r:
+          range_str = '[{0}, '.format(r['min'])
+        elif 'min-ex' in r:
+          range_str = '({0}, '.format(r['min-ex'])
+        else:
+          range_str = '(-inf, '
+
+        if 'max' in r:
+          range_str += '{0}]'.format(r['max'])
+        elif 'max-ex' in r:
+          range_str += '{0})'.format(r['max-ex'])
+        else:
+          range_str += 'inf)'
+
+        raise SchemaRangeMismatch(name+' must be in range '+range_str)
+
+    return validate_range
+
+
+class Factory(object):
+  def __init__(self, register_core_types=True):
+    self.prefix_registry = {
+      '':      'tag:codesimply.com,2008:rx/core/',
+      '.meta': 'tag:codesimply.com,2008:rx/meta/',
+    }
+
+    self.type_registry = {}
+    if register_core_types:
+      for t in core_types: self.register_type(t)
+
+  @staticmethod
+  def _default_prefixes(): pass
+
+  def expand_uri(self, type_name):
+    if re.match('^\w+:', type_name): return type_name
+
+    m = re.match('^/([-._a-z0-9]*)/([-._a-z0-9]+)$', type_name)
+
+    if not m:
+      raise ValueError("couldn't understand type name '{0}'".format(type_name))
+
+    prefix, suffix = m.groups()
+
+    if prefix not in self.prefix_registry:
+      raise KeyError(
+        "unknown prefix '{0}' in type name '{1}'".format(prefix, type_name)
+      )
+
+    return self.prefix_registry[ prefix ] + suffix
+
+  def add_prefix(self, name, base):
+    if self.prefix_registry.get(name):
+      raise SchemaError("the prefix '{0}' is already registered".format(name))
+
+    self.prefix_registry[name] = base;
+
+  def register_type(self, t):
+    t_uri = t.uri()
+
+    if t_uri in self.type_registry:
+      raise ValueError("type already registered for {0}".format(t_uri))
+
+    self.type_registry[t_uri] = t
+
+  def learn_type(self, uri, schema):
+    if self.type_registry.get(uri):
+      raise SchemaError("tried to learn type for already-registered uri {0}".format(uri))
+
+    # make sure schema is valid
+    # should this be in a try/except?
+    self.make_schema(schema)
+
+    self.type_registry[uri] = { 'schema': schema }
+
+  def make_schema(self, schema):
+    if isinstance(schema, str):
+      schema = { 'type': schema }
+
+    if not isinstance(schema, dict):
+      raise SchemaError('invalid schema argument to make_schema')
+
+    uri = self.expand_uri(schema['type'])
+
+    if not self.type_registry.get(uri): raise SchemaError("unknown type {0}".format(uri))
+
+    type_class = self.type_registry[uri]
+
+    if isinstance(type_class, dict):
+      if not {'type'}.issuperset(schema):
+        raise SchemaError('composed type does not take check arguments');
+      return self.make_schema(type_class['schema'])
+    else:
+      return type_class(schema, self)
+
+class _CoreType(object):
+  @classmethod
+  def uri(self):
+    return 'tag:codesimply.com,2008:rx/core/' + self.subname()
+
+  def __init__(self, schema, rx):
+    if not {'type'}.issuperset(schema):
+      raise SchemaError('unknown parameter for //{0}'.format(self.subname()))
+
+  def check(self, value):
+    try:
+      self.validate(value)
+    except SchemaMismatch:
+      return False
+    return True
+
+  def validate(self, value, name='value'):
+    raise SchemaMismatch('Tried to validate abstract base schema class')
+
+class AllType(_CoreType):
+  @staticmethod
+  def subname(): return 'all'
+
+  def __init__(self, schema, rx):
+    if not {'type', 'of'}.issuperset(schema):
+      raise SchemaError('unknown parameter for //all')
+    
+    if not(schema.get('of') and len(schema.get('of'))):
+      raise SchemaError('no alternatives given in //all of')
+
+    self.alts = [rx.make_schema(s) for s in schema['of']]
+
+  def validate(self, value, name='value'):
+    error_messages = []
+    for schema in self.alts:
+      try:
+        schema.validate(value, name)
+      except SchemaMismatch as e:
+        error_messages.append(str(e))
+
+    if len(error_messages) > 1:
+      messages = indent('\n'.join(error_messages))
+      message = '{0} failed to meet all schema requirements:\n{1}'
+      message = message.format(name, messages)
+      raise SchemaMismatch(message)
+    elif len(error_messages) == 1:
+      raise SchemaMismatch(error_messages[0])
+
+class AnyType(_CoreType):
+  @staticmethod
+  def subname(): return 'any'
+
+  def __init__(self, schema, rx):
+    self.alts = None
+
+    if not {'type', 'of'}.issuperset(schema):
+      raise SchemaError('unknown parameter for //any')
+    
+    if 'of' in schema:
+      if not schema['of']: raise SchemaError('no alternatives given in //any of')
+      self.alts = [ rx.make_schema(alt) for alt in schema['of'] ]
+
+  def validate(self, value, name='value'):
+    if self.alts is None:
+      return
+    error_messages = []
+    for schema in self.alts:
+      try:
+        schema.validate(value, name)
+        break
+      except SchemaMismatch as e:
+        error_messages.append(str(e))
+
+    if len(error_messages) == len(self.alts):
+      messages = indent('\n'.join(error_messages))
+      message = '{0} failed to meet any schema requirements:\n{1}'
+      message = message.format(name, messages)
+      raise SchemaMismatch(message)
+
+class ArrType(_CoreType):
+  @staticmethod
+  def subname(): return 'arr'
+
+  def __init__(self, schema, rx):
+    self.length = None
+
+    if not {'type', 'contents', 'length'}.issuperset(schema):
+      raise SchemaError('unknown parameter for //arr')
+
+    if not schema.get('contents'):
+      raise SchemaError('no contents provided for //arr')
+
+    self.content_schema = rx.make_schema(schema['contents'])
+
+    if schema.get('length'):
+      self.length = Util.make_range_validator(schema['length'])
+
+  def validate(self, value, name='value'):
+    if not isinstance(value, (list, tuple)):
+      raise SchemaTypeMismatch(name, 'array')
+
+    if self.length:
+      self.length(len(value), name+' length')
+
+    error_messages = []
+
+    for i, item in enumerate(value):
+      try:
+        self.content_schema.validate(item, 'item '+str(i))
+      except SchemaMismatch as e:
+        error_messages.append(str(e))
+
+    if len(error_messages) > 1:
+      messages = indent('\n'.join(error_messages))
+      message = '{0} sequence contains invalid elements:\n{1}'
+      message = message.format(name, messages)
+      raise SchemaMismatch(message)
+    elif len(error_messages) == 1:
+      raise SchemaMismatch(name+': '+error_messages[0])
+
+class BoolType(_CoreType):
+  @staticmethod
+  def subname(): return 'bool'
+
+  def validate(self, value, name='value'):
+    if not isinstance(value, bool):
+      raise SchemaTypeMismatch(name, 'boolean')
+
+class DefType(_CoreType):
+  @staticmethod
+  def subname(): return 'def'
+
+
+  def validate(self, value, name='value'):
+    if value is None:
+      raise SchemaMismatch(name+' must be non-null')
+
+class FailType(_CoreType):
+  @staticmethod
+  def subname(): return 'fail'
+
+  def check(self, value): return False
+
+  def validate(self, value, name='value'):
+    raise SchemaMismatch(name+' is of fail type, automatically invalid.')
+
+class IntType(_CoreType):
+  @staticmethod
+  def subname(): return 'int'
+
+  def __init__(self, schema, rx):
+    if not {'type', 'range', 'value'}.issuperset(schema):
+      raise SchemaError('unknown parameter for //int')
+
+    self.value = None
+    if 'value' in schema:
+      if not isinstance(schema['value'], Number) or schema['value'] % 1 != 0:
+        raise SchemaError('invalid value parameter for //int')
+      self.value = schema['value']
+
+    self.range = None
+    if 'range' in schema:
+      self.range = Util.make_range_validator(schema['range'])
+
+  def validate(self, value, name='value'):
+    if not isinstance(value, Number) or isinstance(value, bool) or value%1:
+      raise SchemaTypeMismatch(name,'integer')
+
+    if self.range:
+      self.range(value, name)
+
+    if self.value is not None and value != self.value:
+      raise SchemaValueMismatch(name, self.value)
+
+class MapType(_CoreType):
+  @staticmethod
+  def subname(): return 'map'
+
+  def __init__(self, schema, rx):
+    self.allowed = set()
+
+    if not {'type', 'values'}.issuperset(schema):
+      raise SchemaError('unknown parameter for //map')
+
+    if not schema.get('values'):
+      raise SchemaError('no values given for //map')
+
+    self.value_schema = rx.make_schema(schema['values'])
+
+  def validate(self, value, name='value'):
+    if not isinstance(value, dict):
+      raise SchemaTypeMismatch(name, 'map')
+
+    error_messages = []
+
+    for key, val in value.items():
+      try:
+        self.value_schema.validate(val, key)
+      except SchemaMismatch as e:
+        error_messages.append(str(e))
+
+    if len(error_messages) > 1:
+      messages = indent('\n'.join(error_messages))
+      message = '{0} map contains invalid entries:\n{1}'
+      message = message.format(name, messages)
+      raise SchemaMismatch(message)
+    elif len(error_messages) == 1:
+      raise SchemaMismatch(name+': '+error_messages[0])
+
+class NilType(_CoreType):
+  @staticmethod
+  def subname(): return 'nil'
+
+  def check(self, value): return value is None
+
+  def validate(self, value, name='value'):
+    if value is not None:
+      raise SchemaTypeMismatch(name, 'null')
+
+class NumType(_CoreType):
+  @staticmethod
+  def subname(): return 'num'
+
+  def __init__(self, schema, rx):
+    if not {'type', 'range', 'value'}.issuperset(schema):
+      raise SchemaError('unknown parameter for //num')
+
+    self.value = None
+    if 'value' in schema:
+      if not isinstance(schema['value'], Number):
+        raise SchemaError('invalid value parameter for //num')
+      self.value = schema['value']
+
+    self.range = None
+
+    if schema.get('range'):
+      self.range = Util.make_range_validator(schema['range'])
+
+  def validate(self, value, name='value'):
+    if not isinstance(value, Number) or isinstance(value, bool):
+      raise SchemaTypeMismatch(name, 'number')
+
+    if self.range:
+      self.range(value, name)
+
+    if self.value is not None and value != self.value:
+      raise SchemaValueMismatch(name, self.value)
+
+class OneType(_CoreType):
+  @staticmethod
+  def subname(): return 'one'
+
+  def validate(self, value, name='value'):
+    if not isinstance(value, (Number, str)):
+      raise SchemaTypeMismatch(name, 'number or string')
+
+class RecType(_CoreType):
+  @staticmethod
+  def subname(): return 'rec'
+
+  def __init__(self, schema, rx):
+    if not {'type', 'rest', 'required', 'optional'}.issuperset(schema):
+      raise SchemaError('unknown parameter for //rec')
+
+    self.known = set()
+    self.rest_schema = None
+    if schema.get('rest'): self.rest_schema = rx.make_schema(schema['rest'])
+
+    for which in ('required', 'optional'):
+      setattr(self, which, {})
+      for field in schema.get(which, {}).keys():
+        if field in self.known:
+          raise SchemaError('%s appears in both required and optional' % field)
+
+        self.known.add(field)
+
+        self.__getattribute__(which)[field] = rx.make_schema(
+          schema[which][field]
+        )
+
+  def validate(self, value, name='value'):
+    if not isinstance(value, dict):
+      raise SchemaTypeMismatch(name, 'record')
+
+    unknown = [k for k in value.keys() if k not in self.known]
+
+    if unknown and not self.rest_schema:
+      fields = indent('\n'.join(unknown))
+      raise SchemaMismatch(name+' contains unknown fields:\n'+fields)
+
+    error_messages = []
+
+    for field in self.required:
+      try:
+        if field not in value:
+          raise SchemaMismatch('missing required field: '+field)
+        self.required[field].validate(value[field], field)
+      except SchemaMismatch as e:
+        error_messages.append(str(e))
+
+    for field in self.optional:
+      if field not in value: continue
+      try:
+        self.optional[field].validate(value[field], field) 
+      except SchemaMismatch as e:
+        error_messages.append(str(e))
+
+    if unknown:
+      rest = {key: value[key] for key in unknown}
+      try:
+        self.rest_schema.validate(rest, name)
+      except SchemaMismatch as e:
+        error_messages.append(str(e))
+
+    if len(error_messages) > 1:
+      messages = indent('\n'.join(error_messages))
+      message = '{0} record is invalid:\n{1}'
+      message = message.format(name, messages)
+      raise SchemaMismatch(message)
+    elif len(error_messages) == 1:
+      raise SchemaMismatch(name+': '+error_messages[0])
+
+
+class SeqType(_CoreType):
+  @staticmethod
+  def subname(): return 'seq'
+
+  def __init__(self, schema, rx):
+    if not {'type', 'contents', 'tail'}.issuperset(schema):
+      raise SchemaError('unknown parameter for //seq')
+
+    if not schema.get('contents'):
+      raise SchemaError('no contents provided for //seq')
+
+    self.content_schema = [ rx.make_schema(s) for s in schema['contents'] ]
+
+    self.tail_schema = None
+    if (schema.get('tail')):
+      self.tail_schema = rx.make_schema(schema['tail'])
+
+  def validate(self, value, name='value'):
+    if not isinstance(value, (list, tuple)):
+      raise SchemaTypeMismatch(name, 'sequence')
+
+    if len(value) < len(self.content_schema):
+      raise SchemaMismatch(name+' is less than expected length')
+
+    if len(value) > len(self.content_schema) and not self.tail_schema:
+      raise SchemaMismatch(name+' exceeds expected length')
+
+    error_messages = []
+
+    for i, (schema, item) in enumerate(zip(self.content_schema, value)):
+      try:
+        schema.validate(item, 'item '+str(i))
+      except SchemaMismatch as e:
+        error_messages.append(str(e))   
+
+    if len(error_messages) > 1:
+      messages = indent('\n'.join(error_messages))
+      message = '{0} sequence is invalid:\n{1}'
+      message = message.format(name, messages)
+      raise SchemaMismatch(message)
+    elif len(error_messages) == 1:
+      raise SchemaMismatch(name+': '+error_messages[0])
+
+    if len(value) > len(self.content_schema):
+      self.tail_schema.validate(value[len(self.content_schema):], name)
+
+class StrType(_CoreType):
+  @staticmethod
+  def subname(): return 'str'
+
+  def __init__(self, schema, rx):
+    if not {'type', 'value', 'length'}.issuperset(schema):
+      raise SchemaError('unknown parameter for //str')
+
+    self.value = None
+    if 'value' in schema:
+      if not isinstance(schema['value'], str):
+        raise SchemaError('invalid value parameter for //str')
+      self.value = schema['value']
+
+    self.length = None
+    if 'length' in schema:
+      self.length = Util.make_range_validator(schema['length'])
+
+  def validate(self, value, name='value'):
+    if not isinstance(value, str):
+      raise SchemaTypeMismatch(name, 'string')
+    if self.value is not None and value != self.value:
+      raise SchemaValueMismatch(name, '"{0}"'.format(self.value))
+    if self.length:
+      self.length(len(value), name+' length')
+
+core_types = [
+  AllType,  AnyType, ArrType, BoolType, DefType,
+  FailType, IntType, MapType, NilType,  NumType,
+  OneType,  RecType, SeqType, StrType
+]
diff --git a/patacrep/authors.py b/patacrep/authors.py
index 6ea3098b..c8b65361 100644
--- a/patacrep/authors.py
+++ b/patacrep/authors.py
@@ -5,11 +5,6 @@ import re
 
 LOGGER = logging.getLogger(__name__)
 
-DEFAULT_AUTHWORDS = {
-    "after": ["by"],
-    "ignore": ["unknown"],
-    "sep": ["and"],
-    }
 RE_AFTER = r"^.*\b{}\b(.*)$"
 RE_SEPARATOR = r"^(.*)\b *{} *(\b.*)?$"
 
@@ -18,23 +13,17 @@ def compile_authwords(authwords):
 
     This regexp will later be used to match these words in authors strings.
     """
-    # Fill missing values
-    for (key, value) in DEFAULT_AUTHWORDS.items():
-        if key not in authwords:
-            authwords[key] = value
-
-    # Compilation
-    authwords['after'] = [
-        re.compile(RE_AFTER.format(word), re.LOCALE)
-        for word in authwords['after']
-        ]
-    authwords['sep'] = [
-        re.compile(RE_SEPARATOR.format(word), re.LOCALE)
-        for word in ([" %s" % word for word in authwords['sep']] + [',', ';'])
-        ]
-
-    return authwords
-
+    return {
+        'ignore': authwords.get('ignore', []),
+        'after': [
+            re.compile(RE_AFTER.format(word), re.LOCALE)
+            for word in authwords['after']
+            ],
+        'separators': [
+            re.compile(RE_SEPARATOR.format(word), re.LOCALE)
+            for word in ([" %s" % word for word in authwords['separators']] + [',', ';'])
+            ],
+        }
 
 def split_author_names(string):
     r"""Split author between first and last name.
@@ -60,12 +49,12 @@ def split_author_names(string):
     return (chunks[-1].strip(), " ".join(chunks[:-1]).strip())
 
 
-def split_sep_author(string, sep):
+def split_sep_author(string, separators):
     """Split authors string according to separators.
 
     Arguments:
     - string: string containing authors names ;
-    - sep: regexp matching a separator.
+    - separators: regexp matching a separator.
 
     >>> split_sep_author("Tintin and Milou", re.compile(RE_SEPARATOR.format("and")))
     ['Tintin', 'Milou']
@@ -73,12 +62,12 @@ def split_sep_author(string, sep):
     ['Tintin']
     """
     authors = []
-    match = sep.match(string)
+    match = separators.match(string)
     while match:
         if match.group(2) is not None:
             authors.append(match.group(2).strip())
         string = match.group(1)
-        match = sep.match(string)
+        match = separators.match(string)
     authors.insert(0, string.strip())
     return authors
 
@@ -105,7 +94,7 @@ def processauthors_removeparen(authors_string):
             dest += char
     return dest
 
-def processauthors_split_string(authors_string, sep):
+def processauthors_split_string(authors_string, separators):
     """Split strings
 
     See docstring of processauthors() for more information.
@@ -121,7 +110,7 @@ def processauthors_split_string(authors_string, sep):
     ['Tintin', 'Milou']
     """
     authors_list = [authors_string]
-    for sepword in sep:
+    for sepword in separators:
         dest = []
         for author in authors_list:
             dest.extend(split_sep_author(author, sepword))
@@ -171,7 +160,7 @@ def processauthors_clean_authors(authors_list):
         if author.lstrip()
         ]
 
-def processauthors(authors_string, after=None, ignore=None, sep=None):
+def processauthors(authors_string, after=None, ignore=None, separators=None):
     r"""Return an iterator of authors
 
     For example, in the following call:
@@ -186,7 +175,7 @@ def processauthors(authors_string, after=None, ignore=None, sep=None):
     ...   **compile_authwords({
     ...         'after': ["by"],
     ...         'ignore': ["anonymous"],
-    ...         'sep': ["and", ","],
+    ...         'separators': ["and", ","],
     ...         })
     ...   )) == {("Blake", "William"), ("Parry", "Hubert"), ("Royal~Choir~of~FooBar", "The")}
     True
@@ -198,7 +187,7 @@ def processauthors(authors_string, after=None, ignore=None, sep=None):
     # "Lyrics by William Blake, music by Hubert Parry,
                 and sung by The Royal~Choir~of~FooBar"
 
-    2) String is split, separators being comma and words from "sep".
+    2) String is split, separators being comma and words from "separators".
     # ["Lyrics by William Blake", "music by Hubert Parry",
                 "sung by The Royal~Choir~of~FooBar"]
 
@@ -216,8 +205,8 @@ def processauthors(authors_string, after=None, ignore=None, sep=None):
     # ]
     """
 
-    if not sep:
-        sep = []
+    if not separators:
+        separators = []
     if not after:
         after = []
     if not ignore:
@@ -230,17 +219,17 @@ def processauthors(authors_string, after=None, ignore=None, sep=None):
                         processauthors_removeparen(
                             authors_string
                             ),
-                        sep),
+                        separators),
                     after),
                 ignore)
         ):
         yield split_author_names(author)
 
-def process_listauthors(authors_list, after=None, ignore=None, sep=None):
+def process_listauthors(authors_list, after=None, ignore=None, separators=None):
     """Process a list of authors, and return the list of resulting authors."""
     authors = []
     for sublist in [
-            processauthors(string, after, ignore, sep)
+            processauthors(string, after, ignore, separators)
             for string in authors_list
         ]:
         authors.extend(sublist)
diff --git a/patacrep/build.py b/patacrep/build.py
index 2fed6c31..96a09424 100644
--- a/patacrep/build.py
+++ b/patacrep/build.py
@@ -8,10 +8,12 @@ import threading
 import os.path
 from subprocess import Popen, PIPE, call, check_call
 
-from patacrep import authors, content, errors, files
+import yaml
+
+from patacrep import authors, content, encoding, errors, files, pkg_datapath, utils
 from patacrep.index import process_sxd
-from patacrep.templates import TexBookRenderer
-from patacrep.songs import DataSubpath, DEFAULT_CONFIG
+from patacrep.templates import TexBookRenderer, iter_bookoptions
+from patacrep.songs import DataSubpath
 
 LOGGER = logging.getLogger(__name__)
 EOL = "\n"
@@ -40,8 +42,11 @@ class Songbook:
     """
 
     def __init__(self, raw_songbook, basename):
+        # Validate config
+        schema = config_model('schema')
+        utils.validate_yaml_schema(raw_songbook, schema)
+
         self._raw_config = raw_songbook
-        self.config = raw_songbook
         self.basename = basename
         self._errors = list()
         self._config = dict()
@@ -50,14 +55,8 @@ class Songbook:
 
     def _set_datadir(self):
         """Set the default values for datadir"""
-        try:
-            if isinstance(self._raw_config['datadir'], str):
-                self._raw_config['datadir'] = [self._raw_config['datadir']]
-        except KeyError:  # No datadir in the raw_songbook
-            self._raw_config['datadir'] = [os.path.abspath('.')]
-
         abs_datadir = []
-        for path in self._raw_config['datadir']:
+        for path in self._raw_config['_datadir']:
             if os.path.exists(path) and os.path.isdir(path):
                 abs_datadir.append(os.path.abspath(path))
             else:
@@ -65,10 +64,10 @@ class Songbook:
                     "Ignoring non-existent datadir '{}'.".format(path)
                     )
 
-        self._raw_config['datadir'] = abs_datadir
+        self._raw_config['_datadir'] = abs_datadir
         self._raw_config['_songdir'] = [
             DataSubpath(path, 'songs')
-            for path in self._raw_config['datadir']
+            for path in self._raw_config['_datadir']
             ]
 
     def write_tex(self, output):
@@ -78,29 +77,27 @@ class Songbook:
         - output: a file object, in which the file will be written.
         """
         # Updating configuration
-        self._config = DEFAULT_CONFIG.copy()
-        self._config.update(self._raw_config)
+        self._config = self._raw_config.copy()
         renderer = TexBookRenderer(
-            self._config['template'],
-            self._config['datadir'],
-            self._config['lang'],
-            self._config['encoding'],
+            self._config['book']['template'],
+            self._config['_datadir'],
+            self._config['book']['lang'],
+            self._config['book']['encoding'],
             )
-        self._config.update(renderer.get_variables())
-        self._config.update(self._raw_config)
+        self._config['_template'] = renderer.get_all_variables(self._config.get('template', {}))
 
         self._config['_compiled_authwords'] = authors.compile_authwords(
-            copy.deepcopy(self._config['authwords'])
+            copy.deepcopy(self._config['authors'])
             )
 
         # Loading custom plugins
         self._config['_content_plugins'] = files.load_plugins(
-            datadirs=self._config.get('datadir', []),
+            datadirs=self._config['_datadir'],
             root_modules=['content'],
             keyword='CONTENT_PLUGINS',
             )
         self._config['_song_plugins'] = files.load_plugins(
-            datadirs=self._config.get('datadir', []),
+            datadirs=self._config['_datadir'],
             root_modules=['songs'],
             keyword='SONG_RENDERERS',
             )['tsg']
@@ -113,6 +110,8 @@ class Songbook:
             )
         self._config['filename'] = output.name[:-4]
 
+        self._config['bookoptions'] = iter_bookoptions(self._config)
+
         renderer.render_tex(output, self._config)
         self._errors.extend(renderer.errors)
 
@@ -149,7 +148,7 @@ class Songbook:
 
     def requires_lilypond(self):
         """Tell if lilypond is part of the bookoptions"""
-        return 'lilypond' in self.config.get('bookoptions', [])
+        return 'lilypond' in iter_bookoptions(self._config)
 
 def _log_pipe(pipe):
     """Log content from `pipe`."""
@@ -360,3 +359,15 @@ class SongbookBuilder:
                     os.unlink(self.basename + ext)
                 except Exception as exception:
                     raise errors.CleaningError(self.basename + ext, exception)
+
+
+def config_model(*args):
+    """Get the model structure with schema and default options"""
+    model_path = pkg_datapath('templates', 'songbook_model.yml')
+    with encoding.open_read(model_path) as model_file:
+        data = yaml.load(model_file)
+
+    while data and args:
+        name, *args = args
+        data = data.get(name)
+    return data
diff --git a/patacrep/content/include.py b/patacrep/content/include.py
index 92f060ab..dbc10fce 100644
--- a/patacrep/content/include.py
+++ b/patacrep/content/include.py
@@ -41,7 +41,7 @@ def parse(keyword, config, argument, contentlist):
 
     for path in contentlist:
         try:
-            filepath = load_from_datadirs(path, config.get('datadir', []))
+            filepath = load_from_datadirs(path, config['_datadir'])
         except ContentError as error:
             new_contentlist.append_error(error)
             continue
@@ -49,7 +49,7 @@ def parse(keyword, config, argument, contentlist):
         try:
             with encoding.open_read(
                 filepath,
-                encoding=config['encoding']
+                encoding=config['book']['encoding']
                 ) as content_file:
                 new_content = json.load(content_file)
         except Exception as error: # pylint: disable=broad-except
@@ -59,9 +59,9 @@ def parse(keyword, config, argument, contentlist):
                 ))
             continue
 
-        config["datadir"].append(os.path.abspath(os.path.dirname(filepath)))
+        config['_datadir'].append(os.path.abspath(os.path.dirname(filepath)))
         new_contentlist.extend(process_content(new_content, config))
-        config["datadir"].pop()
+        config['_datadir'].pop()
 
     return new_contentlist
 
diff --git a/patacrep/content/tex.py b/patacrep/content/tex.py
index 2f20f70b..dd506655 100755
--- a/patacrep/content/tex.py
+++ b/patacrep/content/tex.py
@@ -38,8 +38,8 @@ def parse(keyword, argument, contentlist, config):
     filelist = ContentList()
     basefolders = itertools.chain(
         (path.fullpath for path in config['_songdir']),
-        files.iter_datadirs(config['datadir']),
-        files.iter_datadirs(config['datadir'], 'latex'),
+        files.iter_datadirs(config['_datadir']),
+        files.iter_datadirs(config['_datadir'], 'latex'),
         )
     for filename in contentlist:
         checked_file = None
diff --git a/patacrep/data/templates/default.tex b/patacrep/data/templates/default.tex
index a9504965..5fbf5c10 100644
--- a/patacrep/data/templates/default.tex
+++ b/patacrep/data/templates/default.tex
@@ -19,34 +19,33 @@
 %!- https://github.com/patacrep/
 
 (* variables *)
-{
-"classoptions": {"description": {"en": "LaTeX class options", "fr": "Options de la classe LaTeX"},
-               "type": "flag",
-               "join": ",",
-               "mandatory": true,
-               "default": {"default":[]}
-            },
-"title": {"description": {"en": "Title", "fr": "Titre"},
-            "default": {"en": "Guitar songbook", "fr": "Recueil de chansons pour guitare"},
-            "mandatory":true
-         },
-"author": {"description": {"en": "Author", "fr": "Auteur"},
-            "default": {"en": "The Patacrep Team", "fr": "L'équipe Patacrep"},
-            "mandatory":true
-         },
-"notenamesout": {"description": {"en": "Note names. Can be 'solfedge' (Do, Re, Mi...) or 'alphascale' (A, B, C...).",
-                              "fr": "Nom des notes : 'solfedge' (Do, Ré, Mi...) ou 'alphascale' (A, B, C...)."},
-                  "default": {"default": "alphascale", "fr": "solfedge"}
-                  }
-}
+schema:
+  type: //rec
+  required:
+    title:
+      type: //str
+    author:
+      type: //str
+  optional:
+    classoptions:
+      type: //arr
+      contents: //str
+default:
+  title: "Guitar songbook"
+  author: "The Patacrep Team"
+description.en:
+  title: "Title"
+  author: "Author"
+  classoptions: "LaTeX class options"
 (* endvariables -*)
 
 (*- extends "songs.tex" -*)
 (*- set indexes = "titleidx,authidx" -*)
+(*- set template_var = _template["default.tex"] -*)
 
 (* block documentclass *)
 \documentclass[
-    (* for option in classoptions *)
+    (* for option in template_var.classoptions *)
     ((option)),
     (* endfor *)
     ]{article}
@@ -58,8 +57,8 @@
 
 \usepackage{chords}
 
-\title{((title))}
-\author{((author))}
+\title{(( template_var.title ))}
+\author{(( template_var.author ))}
 
 \newindex{titleidx}{((filename))_title}
 \newauthorindex{authidx}{((filename))_auth}
@@ -67,17 +66,17 @@
 (* for prefix in titleprefixwords -*)
    \titleprefixword{((prefix))}
 (* endfor*)
-(* for word in authwords.ignore -*)
+(* for word in authors.ignore -*)
    \authignoreword{((word))}
 (* endfor *)
-(* for word in authwords.after -*)
+(* for word in authors.after -*)
    \authbyword{((word))}
 (* endfor *)
-(* for word in authwords.sep -*)
+(* for word in authors.separators -*)
    \authsepword{((word))}
 (* endfor *)
 
-(* if notenamesout=="alphascale" -*)
+(* if chords.notation=="alphascale" -*)
   \notenamesout{A}{B}{C}{D}{E}{F}{G}
 (* else -*)
   \notenamesout{La}{Si}{Do}{R\'e}{Mi}{Fa}{Sol}
diff --git a/patacrep/data/templates/layout.tex b/patacrep/data/templates/layout.tex
index 63227530..ea048417 100644
--- a/patacrep/data/templates/layout.tex
+++ b/patacrep/data/templates/layout.tex
@@ -27,7 +27,7 @@
 
 \makeatletter
 \def\input@path{ %
-    (* for dir in datadir|iter_datadirs *)
+    (* for dir in _datadir|iter_datadirs *)
         {(( dir | path2posix ))/latex/} %
     (* endfor *)
 }
diff --git a/patacrep/data/templates/patacrep.tex b/patacrep/data/templates/patacrep.tex
index b9a01f1e..48cb7bd4 100644
--- a/patacrep/data/templates/patacrep.tex
+++ b/patacrep/data/templates/patacrep.tex
@@ -19,60 +19,51 @@
 %!- https://github.com/patacrep/
 
 (* variables *)
-{
-"subtitle": {"description": {"en": "Subtitle", "fr": "Sous-titre"},
-            "default": {"default": ""}
-            },
-"version":{ "description": {"en": "Version", "fr": "Version"},
-            "default": {"default": "undefined"}
-         },
-"web": {"description": {"en": "Website", "fr": "Site web"},
-         "default": {"default": "http://www.patacrep.com"}
-      },
-"mail": {"description": {"en": "Email", "fr": "Adresse électronique"},
-         "default": {"default": "crep@team-on-fire.com"}
-      },
-"picture": {"description": {"en": "Cover picture", "fr": "Image de couverture"},
-            "type": "file",
-            "default": {"default": "img/treble_a"}
-         },
-"picturecopyright": {"description": {"en": "Copyright for the cover picture", "fr": "Copyright pour l'image de couverture"},
-                     "default": {"default": "Dbolton \\url{http://commons.wikimedia.org/wiki/User:Dbolton}"}
-                  },
-"footer": {"description": {"en": "Footer", "fr": "Pied de page"},
-           "default": {"default": "Generated using Songbook (\\url{http://www.patacrep.com})"}
-        },
-"songnumberbgcolor": {"description": {"en": "Number Shade", "fr": "Couleur des numéros"},
-                     "type": "color",
-                     "default": {"default": "D1E4AE"}
-                  },
-"notebgcolor": {"description": {"en": "Note Shade", "fr": "Couleur des notes"},
-               "type": "color",
-               "default": {"default": "D1E4AE"}
-            },
-"indexbgcolor": {"description": {"en": "Index Shade", "fr": "Couleur d'index"},
-               "type": "color",
-               "default": {"default": "D1E4AE"}
-            },
-"titleprefixwords": {"description": {"en": "Ignore some words in the beginning of song titles",
-                                     "fr": "Ignore des mots dans le classement des chansons"},
-                     "default": {"default": ["The", "Le", "La", "L'", "A", "Au", "Ces", "De",
-                     						 "Des", "El", "Les", "Ma", "Mon", "Un"]}
-                     }
-}
+schema:
+  type: //rec
+  optional:
+    version: //str
+  required:
+    subtitle: //str
+    url: //str
+    email: //str
+    picture: //str
+    picturecopyright: //str
+    footer: //str
+    color:
+      type: //rec
+      required:
+        songlink: //str
+        hyperlink: //str
+    bgcolor:
+      type: //rec
+      required:
+        songnumber: //str
+        note: //str
+        index: //str
+
+default:
+  subtitle: ""
+  version: ""
+  url: http://www.patacrep.com"
+  email: crep@team-on-fire.com
+  picture: img/treble_a
+  picturecopyright: "Dbolton \\url{http://commons.wikimedia.org/wiki/User:Dbolton}"
+  footer: "Generated using Songbook (\\url{http://www.patacrep.com})"
+  color:
+    songlink: 4e9a06
+    hyperlink: 204a87
+  bgcolor:
+    songnumber: D1E4AE
+    note: D1E4AE
+    index: D1E4AE
 (* endvariables -*)
 
 (*- extends "default.tex" -*)
 
 (* block songbookpackages *)
-%! booktype, bookoptions and instruments are defined in "songs.tex"
 \usepackage[
-    ((booktype)),
-    (* for option in bookoptions *)
-    ((option)),
-    (* endfor *)
-    (* for instrument in instruments *)
-    ((instrument)),
+    (* for option in bookoptions *)((option)),
     (* endfor *)
     ]{crepbook}
 (* endblock *)
@@ -91,16 +82,18 @@
 
 \pagestyle{empty}
 
-\definecolor{SongNumberBgColor}{HTML}{((songnumberbgcolor))}
-\definecolor{NoteBgColor}{HTML}{((notebgcolor))}
-\definecolor{IndexBgColor}{HTML}{((indexbgcolor))}
+(*- set template_var = _template["patacrep.tex"] -*)
+
+\definecolor{SongNumberBgColor}{HTML}{(( template_var.bgcolor.songnumber ))}
+\definecolor{NoteBgColor}{HTML}{(( template_var.bgcolor.note ))}
+\definecolor{IndexBgColor}{HTML}{(( template_var.bgcolor.index ))}
 
 \renewcommand{\snumbgcolor}{SongNumberBgColor}
 \renewcommand{\notebgcolor}{NoteBgColor}
 \renewcommand{\idxbgcolor}{IndexBgColor}
 
-\definecolor{tango-green-3}{HTML}{4e9a06}
-\definecolor{tango-blue-3}{HTML}{204a87}
+\definecolor{tango-green-3}{HTML}{(( template_var.color.songlink ))}
+\definecolor{tango-blue-3}{HTML}{(( template_var.color.hyperlink ))}
 \usepackage[
     bookmarks,
     bookmarksopen,
@@ -111,13 +104,13 @@
     ]{hyperref}
 
 
-\subtitle{((subtitle))}
-(* if version!="undefined" -*)
-    \version{((version))}
+\subtitle{(( template_var.subtitle ))}
+(* if template_var.version -*)
+    \version{(( template_var.version ))}
 (* endif *)
-\mail{((mail))}
-\web{((web))}
-\picture{((picture))}
-\picturecopyright{((picturecopyright))}
-\footer{((footer))}
+\mail{(( template_var.email ))}
+\web{(( template_var.url ))}
+\picture{(( template_var.picture ))}
+\picturecopyright{(( template_var.picturecopyright ))}
+\footer{(( template_var.footer ))}
 (* endblock *)
diff --git a/patacrep/data/templates/songbook_model.yml b/patacrep/data/templates/songbook_model.yml
new file mode 100644
index 00000000..7567de47
--- /dev/null
+++ b/patacrep/data/templates/songbook_model.yml
@@ -0,0 +1,121 @@
+schema:
+  type: //rec
+  optional:
+    content: //any
+    template: //any
+  required:
+    _cache: //bool
+    _datadir:
+      type: //arr
+      contents: //str
+    book:
+      type: //rec
+      required:
+        encoding: //str
+        lang: //str
+        pictures: //bool
+        template: //str
+        onesongperpage: //bool
+    chords:
+      type: //rec
+      required:
+        show: //bool
+        diagrampage: //bool
+        repeatchords: //bool
+        lilypond: //bool
+        tablatures: //bool
+        diagramreminder:
+          type: //any
+          of:
+            - type: //str
+              value: "none"
+            - type: //str
+              value: "important"
+            - type: //str
+              value: "all"
+        instrument:
+          type: //any
+          of:
+            - type: //str
+              value: "guitar"
+            - type: //str
+              value: "ukulele"
+        notation:
+          type: //any
+          of:
+            - type: //str
+              value: "alphascale"
+            - type: //str
+              value: "solfedge"
+    authors:
+      type: //rec
+      required:
+        separators:
+          type: //any
+          of:
+            - type: //arr
+              contents: //str
+            - type: //nil
+        ignore:
+          type: //any
+          of:
+            - type: //arr
+              contents: //str
+            - type: //nil
+        after:
+          type: //any
+          of:
+            - type: //arr
+              contents: //str
+            - type: //nil
+    titles:
+      type: //rec
+      required:
+        prefix:
+          type: //any
+          of:
+            - type: //arr
+              contents: //str
+            - type: //nil
+default:
+  book:
+    lang: en
+    encoding: utf-8
+    pictures: yes
+    template: default.tex
+    onesongperpage: no
+
+  chords: # Options relatives aux accords
+    show: yes
+    diagramreminder: important
+    diagrampage: yes
+    repeatchords: yes
+    lilypond: no
+    tablatures: no
+    instrument: guitar
+    notation: alphascale
+
+  authors: # Comment sont analysés les auteurs
+    separators:
+    - and
+    ignore:
+    - unknown
+    after:
+    - by
+
+  titles: # Comment sont analysés les titres
+    prefix:
+    - The
+    - Le
+    - La
+    - "L'"
+    - A
+    - Au
+    - Ces
+    - De
+    - Des
+    - El
+    - Les
+    - Ma
+    - Mon
+    - Un
diff --git a/patacrep/data/templates/songs.tex b/patacrep/data/templates/songs.tex
index 07ed0f33..94846f0d 100644
--- a/patacrep/data/templates/songs.tex
+++ b/patacrep/data/templates/songs.tex
@@ -18,62 +18,12 @@
 %!- The latest version of this program can be obtained from
 %!- https://github.com/patacrep/
 
-(* variables *)
-{
-"instruments": {"description": {"en": "Instruments", "fr": "Instruments"},
-               "type": "flag",
-               "values": {"guitar": {"en": "Guitare", "fr": "Guitare"},
-                          "ukulele": {"en": "Ukulele", "fr": "Ukulele"}
-                         },
-               "join": ",",
-               "mandatory": true,
-               "default": {"default":["guitar"]}
-            },
-"bookoptions": {"description": {"en": "Options", "fr": "Options"},
-               "type": "flag",
-               "values": {"diagram": {"en": "Chords diagrams", "fr": "Diagrammes d'accords"},
-                          "importantdiagramonly": {"en": "Only importants diagrames", "fr": "Diagrammes importants uniquement"},
-                          "lilypond": {"en": "Lilypond music sheets", "fr": "Partitions lilypond"},
-                          "pictures": {"en": "Cover pictures", "fr": "Couvertures d'albums"},
-                          "tabs": {"en": "Tablatures", "fr": "Tablatures"},
-                          "repeatchords": {"en": "Repeat chords", "fr": "Répéter les accords"},
-                          "onesongperpage": {"en": "One song per page", "fr": "Une chanson par page"}
-                       },
-               "join": ",",
-               "mandatory": true,
-               "default": {"default":["diagram","pictures"]}
-            },
-"booktype": {"description": {"en": "Type", "fr": "Type"},
-            "type": "enum",
-            "values": {"chorded": {"en": "With guitar chords", "fr": "Avec accords de guitare" },
-                                   "lyric": {"en": "Lyrics only", "fr": "Paroles uniquement"}
-                     },
-            "default": {"default":"chorded"},
-            "mandatory": true
-            },
-"lang": {"description": {"en": "Language", "fr": "Langue"},
-         "default": {"en": "en", "fr": "fr"}
-      },
-"titleprefixwords": {"description": {"en": "Ignore some words in the beginning of song titles",
-                                     "fr": "Ignore des mots dans le classement des chansons"},
-                     "default": {"default": []}
-                     },
-"authwords": {"description": {"en": "Set of options to process author string (LaTeX commands authsepword, authignoreword, authbyword)",
-                              "fr": "Options pour traiter les noms d'auteurs (commandes LaTeX authsepword, authignoreword, authbyword)"},
-               "default": {"default": {}}
-               }
-}
-(* endvariables -*)
-
 (*- extends "layout.tex" -*)
 
 (* block songbookpackages *)
 \usepackage[
-    ((booktype)),
     (* for option in bookoptions *)((option)),
     (* endfor *)
-    (* for instrument in instruments *)((instrument)),
-    (* endfor *)
     ]{patacrep}
 (* endblock *)
 
@@ -83,12 +33,12 @@
 (* for lang in _langs|sort -*)
     \PassOptionsToPackage{(( lang | lang2babel ))}{babel}
 (* endfor *)
-\usepackage[(( lang | lang2babel ))]{babel}
-\lang{(( lang | lang2babel ))}
+\usepackage[(( book.lang | lang2babel ))]{babel}
+\lang{(( book.lang | lang2babel ))}
 
 \usepackage{graphicx}
 \graphicspath{ %
-    (* for dir in datadir|iter_datadirs*)
+    (* for dir in _datadir|iter_datadirs*)
         {(( dir | path2posix ))/} %
     (* endfor *)
 }
diff --git a/patacrep/index.py b/patacrep/index.py
index 767c04ba..d572f872 100644
--- a/patacrep/index.py
+++ b/patacrep/index.py
@@ -77,6 +77,9 @@ class Index:
 
     def add_keyword(self, key, word):
         """Add 'word' to self.keywords[key]."""
+        # Because LaTeX uses 'sep'
+        if key == 'sep':
+            key = 'separators'
         if key not in self.keywords:
             self.keywords[key] = []
         self.keywords[key].append(word)
diff --git a/patacrep/songbook/__main__.py b/patacrep/songbook/__main__.py
index b62dcf73..adc581c5 100644
--- a/patacrep/songbook/__main__.py
+++ b/patacrep/songbook/__main__.py
@@ -8,8 +8,8 @@ import textwrap
 import sys
 import yaml
 
-from patacrep.build import SongbookBuilder, DEFAULT_STEPS
-from patacrep.utils import yesno
+from patacrep.build import SongbookBuilder, DEFAULT_STEPS, config_model
+from patacrep.utils import yesno, DictOfDict
 from patacrep import __version__
 from patacrep import errors
 import patacrep.encoding
@@ -133,39 +133,46 @@ def main():
 
     basename = os.path.basename(songbook_path)[:-3]
 
+    # Load the user songbook config
     try:
         with patacrep.encoding.open_read(songbook_path) as songbook_file:
-            songbook = yaml.load(songbook_file)
-        if 'encoding' in songbook:
+            user_songbook = yaml.load(songbook_file)
+        if 'encoding' in user_songbook:
             with patacrep.encoding.open_read(
                 songbook_path,
-                encoding=songbook['encoding']
+                encoding=user_songbook['encoding']
                 ) as songbook_file:
-                songbook = yaml.load(songbook_file)
+                user_songbook = yaml.load(songbook_file)
     except Exception as error: # pylint: disable=broad-except
         LOGGER.error(error)
         LOGGER.error("Error while loading file '{}'.".format(songbook_path))
         sys.exit(1)
 
+    # Merge the default and user configs
+    default_songbook = DictOfDict(config_model('default'))
+    default_songbook.update(user_songbook)
+    songbook = dict(default_songbook)
+
     # Gathering datadirs
     datadirs = []
     if options.datadir:
         # Command line options
         datadirs += [item[0] for item in options.datadir]
-    if 'datadir' in songbook:
-        if isinstance(songbook['datadir'], str):
-            songbook['datadir'] = [songbook['datadir']]
+    if 'book' in songbook and 'datadir' in songbook['book']:
+        if isinstance(songbook['book']['datadir'], str):
+            songbook['book']['datadir'] = [songbook['book']['datadir']]
         datadirs += [
             os.path.join(
                 os.path.dirname(os.path.abspath(songbook_path)),
                 path
                 )
-            for path in songbook['datadir']
+            for path in songbook['book']['datadir']
             ]
+        del songbook['book']['datadir']
+
     # Default value
     datadirs.append(os.path.dirname(os.path.abspath(songbook_path)))
-
-    songbook['datadir'] = datadirs
+    songbook['_datadir'] = datadirs
     songbook['_cache'] = options.cache[0]
 
     try:
diff --git a/patacrep/songs/__init__.py b/patacrep/songs/__init__.py
index 3745ab9e..adf473c5 100644
--- a/patacrep/songs/__init__.py
+++ b/patacrep/songs/__init__.py
@@ -14,15 +14,6 @@ from patacrep.songs import errors as song_errors
 
 LOGGER = logging.getLogger(__name__)
 
-DEFAULT_CONFIG = {
-    'template': "default.tex",
-    'lang': 'en',
-    'content': [],
-    'titleprefixwords': [],
-    'encoding': None,
-    'datadir': [],
-    }
-
 def cached_name(datadir, filename):
     """Return the filename of the cache version of the file."""
     fullpath = os.path.abspath(os.path.join(datadir, '.cache', filename))
@@ -107,7 +98,7 @@ class Song:
 
     def __init__(self, subpath, config=None, *, datadir=None):
         if config is None:
-            config = DEFAULT_CONFIG.copy()
+            config = {}
 
         if datadir is None:
             self.datadir = ""
@@ -120,8 +111,8 @@ class Song:
         self.fullpath = os.path.join(self.datadir, subpath)
         self.subpath = subpath
         self._filehash = None
-        self.encoding = config["encoding"]
-        self.lang = config["lang"]
+        self.encoding = config['book']["encoding"]
+        self.lang = config['book']["lang"]
         self.config = config
         self.errors = []
 
@@ -138,7 +129,7 @@ class Song:
         self.unprefixed_titles = [
             unprefixed_title(
                 title,
-                config['titleprefixwords']
+                config['titles']['prefix']
                 )
             for title
             in self.titles
@@ -230,7 +221,7 @@ class Song:
     def iter_datadirs(self, *subpath):
         """Return an iterator of existing datadirs (with an optionnal subpath)
         """
-        yield from files.iter_datadirs(self.config['datadir'], *subpath)
+        yield from files.iter_datadirs(self.config['_datadir'], *subpath)
 
     def search_datadir_file(self, filename, extensions=None, directories=None):
         """Search for a file name.
@@ -258,7 +249,7 @@ class Song:
         if extensions is None:
             extensions = ['']
         if directories is None:
-            directories = self.config['datadir']
+            directories = self.config['_datadir']
 
         songdir = os.path.dirname(self.fullpath)
         for extension in extensions:
diff --git a/patacrep/songs/convert/__main__.py b/patacrep/songs/convert/__main__.py
index 19d7041e..1c2e8cfb 100644
--- a/patacrep/songs/convert/__main__.py
+++ b/patacrep/songs/convert/__main__.py
@@ -33,6 +33,7 @@ if __name__ == "__main__":
     dest = sys.argv[2]
     song_files = sys.argv[3:]
 
+    # todo : what is the datadir argument used for?
     renderers = files.load_plugins(
         datadirs=DEFAULT_CONFIG.get('datadir', []),
         root_modules=['songs'],
diff --git a/patacrep/templates.py b/patacrep/templates.py
index 9194cf7f..f745a58e 100644
--- a/patacrep/templates.py
+++ b/patacrep/templates.py
@@ -2,14 +2,15 @@
 
 import logging
 import re
-import json
+
+import yaml
 
 from jinja2 import Environment, FileSystemLoader, ChoiceLoader, \
         TemplateNotFound, nodes
 from jinja2.ext import Extension
 from jinja2.meta import find_referenced_templates as find_templates
 
-from patacrep import errors, files
+from patacrep import errors, files, utils
 from patacrep.latex import lang2babel, UnknownLanguage
 import patacrep.encoding
 
@@ -160,37 +161,28 @@ class TexBookRenderer(Renderer):
                     ),
                 )
 
-    def get_variables(self):
-        '''Get and return a dictionary with the default values
-         for all the variables
+    def get_all_variables(self, user_config):
+        '''
+        Validate template variables (and set defaults when needed)
         '''
         data = self.get_template_variables(self.template)
         variables = dict()
         for name, param in data.items():
-            variables[name] = self._get_default(param)
+            template_config = user_config.get(name, {})
+            variables[name] = self._get_variables(param, template_config)
         return variables
 
-    def _get_default(self, parameter):
+    @staticmethod
+    def _get_variables(parameter, user_config):
         '''Get the default value for the parameter, according to the language.
         '''
-        default = None
-        try:
-            default = parameter['default']
-        except KeyError:
-            return None
-
-        if self.lang in default:
-            variable = default[self.lang]
-        elif "default" in default:
-            variable = default["default"]
-        elif "en" in default:
-            variable = default["en"]
-        elif len(default):
-            variable = default.popitem()[1]
-        else:
-            variable = None
-
-        return variable
+        schema = parameter.get('schema', {})
+
+        data = utils.DictOfDict(parameter.get('default', {}))
+        data.update(user_config)
+
+        utils.validate_yaml_schema(data, schema)
+        return data
 
     def get_template_variables(self, template, skip=None):
         """Parse the template to extract the variables as a dictionary.
@@ -206,16 +198,19 @@ class TexBookRenderer(Renderer):
             skip = []
         variables = {}
         (current, templates) = self.parse_template(template)
+        if current:
+            variables[template.name] = current
+
         for subtemplate in templates:
             if subtemplate in skip:
                 continue
+            subtemplate = self.jinjaenv.get_template(subtemplate)
             variables.update(
                 self.get_template_variables(
                     subtemplate,
                     skip + templates
                     )
                 )
-        variables.update(current)
         return variables
 
     def parse_template(self, template):
@@ -242,17 +237,17 @@ class TexBookRenderer(Renderer):
         if match:
             for var in match:
                 try:
-                    subvariables.update(json.loads(var))
+                    subvariables.update(yaml.load(var))
                 except ValueError as exception:
                     raise errors.TemplateError(
                         exception,
                         (
-                            "Error while parsing json in file "
-                            "{filename}. The json string was:"
-                            "\n'''\n{jsonstring}\n'''"
+                            "Error while parsing yaml in file "
+                            "{filename}. The yaml string was:"
+                            "\n'''\n{yamlstring}\n'''"
                         ).format(
                             filename=templatename,
-                            jsonstring=var,
+                            yamlstring=var,
                             )
                         )
 
@@ -267,3 +262,42 @@ class TexBookRenderer(Renderer):
         '''
 
         output.write(self.template.render(context))
+
+
+def transform_options(config, equivalents):
+    """
+    Get the equivalent name of the checked options
+    """
+    for option in config:
+        if config[option] and option in equivalents:
+            yield equivalents[option]
+
+def iter_bookoptions(config):
+    """
+    Extract the bookoptions from the config structure
+    """
+    if config['chords']['show']:
+        yield 'chorded'
+    else:
+        yield 'lyrics'
+
+    book_equivalents = {
+        'pictures':         'pictures',
+        'onesongperpage':   'onesongperpage',
+    }
+    yield from transform_options(config['book'], book_equivalents)
+
+    chords_equivalents = {
+        'lilypond':     'lilypond',
+        'tablatures':   'tabs',
+        'repeatchords': 'repeatchords',
+    }
+    yield from transform_options(config['chords'], chords_equivalents)
+
+    if config['chords']['show']:
+        if config['chords']['diagramreminder'] == "important":
+            yield 'importantdiagramonly'
+        elif config['chords']['diagramreminder'] == "all":
+            yield 'diagram'
+
+        yield config['chords']['instrument']
diff --git a/patacrep/utils.py b/patacrep/utils.py
index 998fe738..7ddd0eca 100644
--- a/patacrep/utils.py
+++ b/patacrep/utils.py
@@ -2,6 +2,8 @@
 
 from collections import UserDict
 
+from patacrep import errors, Rx
+
 class DictOfDict(UserDict):
     """Dictionary, with a recursive :meth:`update` method.
 
@@ -75,3 +77,20 @@ def yesno(string):
         string,
         ", ".join(["'{}'".format(string) for string in yes_strings + no_strings]),
         ))
+
+def validate_yaml_schema(data, schema):
+    """Check that the data respects the schema
+
+    Will raise `SBFileError` if the schema is not respected.
+    """
+    rx_checker = Rx.Factory({"register_core_types": True})
+    schema = rx_checker.make_schema(schema)
+
+    if not isinstance(data, dict):
+        data = dict(data)
+
+    try:
+        schema.validate(data)
+    except Rx.SchemaMismatch as exception:
+        msg = 'Could not parse songbook file:\n' + str(exception)
+        raise errors.SBFileError(msg)
diff --git a/test/test_authors.py b/test/test_authors.py
index 8e560102..659e0993 100644
--- a/test/test_authors.py
+++ b/test/test_authors.py
@@ -49,7 +49,7 @@ PROCESS_AUTHORS_DATA = [
 AUTHWORDS = authors.compile_authwords({
     "after": ["by"],
     "ignore": ["anonymous", "Anonyme", "anonyme"],
-    "sep": ['and', 'et'],
+    "separators": ['and', 'et'],
     })
 
 class TestAutors(unittest.TestCase):
diff --git a/test/test_content/test_content.py b/test/test_content/test_content.py
index 5857506c..23d498bc 100644
--- a/test/test_content/test_content.py
+++ b/test/test_content/test_content.py
@@ -7,9 +7,10 @@ import os
 import unittest
 import json
 
-from patacrep.songs import DataSubpath, DEFAULT_CONFIG
+from patacrep.songs import DataSubpath
 from patacrep import content, files
 from patacrep.content import song, section, songsection, tex
+from patacrep.build import config_model
 
 from .. import logging_reduced
 from .. import dynamic # pylint: disable=unused-import
@@ -95,11 +96,12 @@ class FileTest(unittest.TestCase, metaclass=dynamic.DynamicTest):
     def _generate_config(cls):
         """Generate the config to process the content"""
 
-        config = DEFAULT_CONFIG.copy()
+        # Load the default songbook config
+        config = config_model('default')
 
         datadirpaths = [os.path.join(os.path.dirname(__file__), 'datadir')]
 
-        config['datadir'] = datadirpaths
+        config['_datadir'] = datadirpaths
 
         config['_songdir'] = [
             DataSubpath(path, 'songs')
diff --git a/test/test_song/test_parser.py b/test/test_song/test_parser.py
index 298f0017..5dacf81d 100644
--- a/test/test_song/test_parser.py
+++ b/test/test_song/test_parser.py
@@ -9,8 +9,8 @@ import unittest
 from pkg_resources import resource_filename
 
 from patacrep import files
-from patacrep.songs import DEFAULT_CONFIG
 from patacrep.encoding import open_read
+from patacrep.build import config_model
 from patacrep.songs import errors
 
 from .. import logging_reduced
@@ -75,13 +75,15 @@ class FileTest(unittest.TestCase, metaclass=dynamic.DynamicTest):
     def _iter_testmethods(cls):
         """Iterate over song files to test."""
         # Setting datadir
-        cls.config = DEFAULT_CONFIG
-        if 'datadir' not in cls.config:
-            cls.config['datadir'] = []
-        cls.config['datadir'].append('datadir')
+        # Load the default songbook config
+        cls.config = config_model('default')
+
+        if '_datadir' not in cls.config:
+            cls.config['_datadir'] = []
+        cls.config['_datadir'].append('datadir')
 
         cls.song_plugins = files.load_plugins(
-            datadirs=cls.config['datadir'],
+            datadirs=cls.config['_datadir'],
             root_modules=['songs'],
             keyword='SONG_RENDERERS',
             )
diff --git a/test/test_songbook/content.sb b/test/test_songbook/content.sb
index 99042d25..7e5ee2c8 100644
--- a/test/test_songbook/content.sb
+++ b/test/test_songbook/content.sb
@@ -1,6 +1,12 @@
-{
-"datadir": ["content_datadir"],
-"content": [
+book:
+  pictures: yes
+  datadir: content_datadir
+  lang: en
+chords:
+  repeatchords: no
+  diagramreminder: all
+
+content: [
   ["section", "Test of section"],
   ["sorted"],
   ["songsection", "Test of song section"],
@@ -9,5 +15,4 @@
     ["tex", "foo.tex"]
   ],
   ["include", "include.sbc"]
-  ]
-}
+  ]
\ No newline at end of file
diff --git a/test/test_songbook/content.tex.control b/test/test_songbook/content.tex.control
index 02606184..4120642f 100644
--- a/test/test_songbook/content.tex.control
+++ b/test/test_songbook/content.tex.control
@@ -23,9 +23,9 @@
     ]{article}
 
 \usepackage[
-    chorded,
-diagram,
+chorded,
 pictures,
+diagram,
 guitar,
     ]{patacrep}
 
@@ -63,6 +63,9 @@ guitar,
 \newindex{titleidx}{content_title}
 \newauthorindex{authidx}{content_auth}
 
+\authignoreword{unknown}
+\authbyword{by}
+\authsepword{and}
 
 \notenamesout{A}{B}{C}{D}{E}{F}{G}
 
diff --git a/test/test_songbook/datadir.sb b/test/test_songbook/datadir.sb
index f44c3dba..0763bc7a 100644
--- a/test/test_songbook/datadir.sb
+++ b/test/test_songbook/datadir.sb
@@ -1,6 +1,6 @@
-bookoptions:
-- pictures
-datadir:
-- datadir_datadir
-- datadir_datadir2
-lang: en
+book:
+  pictures: yes
+  datadir:
+    - datadir_datadir
+    - datadir_datadir2
+  lang: en
diff --git a/test/test_songbook/datadir.tex.control b/test/test_songbook/datadir.tex.control
index afc99160..56bee48e 100644
--- a/test/test_songbook/datadir.tex.control
+++ b/test/test_songbook/datadir.tex.control
@@ -24,8 +24,10 @@
     ]{article}
 
 \usepackage[
-    chorded,
+chorded,
 pictures,
+repeatchords,
+importantdiagramonly,
 guitar,
     ]{patacrep}
 
@@ -64,6 +66,9 @@ guitar,
 \newindex{titleidx}{datadir_title}
 \newauthorindex{authidx}{datadir_auth}
 
+\authignoreword{unknown}
+\authbyword{by}
+\authsepword{and}
 
 \notenamesout{A}{B}{C}{D}{E}{F}{G}
 
diff --git a/test/test_songbook/languages.sb b/test/test_songbook/languages.sb
index ff589a74..43e7ab85 100644
--- a/test/test_songbook/languages.sb
+++ b/test/test_songbook/languages.sb
@@ -1,2 +1,3 @@
-datadir:
-- languages_datadir
+book:
+  datadir:
+  - languages_datadir
diff --git a/test/test_songbook/languages.tex.control b/test/test_songbook/languages.tex.control
index 6f08614f..c8b8cfd2 100644
--- a/test/test_songbook/languages.tex.control
+++ b/test/test_songbook/languages.tex.control
@@ -23,9 +23,10 @@
     ]{article}
 
 \usepackage[
-    chorded,
-diagram,
+chorded,
 pictures,
+repeatchords,
+importantdiagramonly,
 guitar,
     ]{patacrep}
 
@@ -65,6 +66,9 @@ guitar,
 \newindex{titleidx}{languages_title}
 \newauthorindex{authidx}{languages_auth}
 
+\authignoreword{unknown}
+\authbyword{by}
+\authsepword{and}
 
 \notenamesout{A}{B}{C}{D}{E}{F}{G}
 
diff --git a/test/test_songbook/syntax.sb b/test/test_songbook/syntax.sb
index 4b1f4ef2..aca40b87 100644
--- a/test/test_songbook/syntax.sb
+++ b/test/test_songbook/syntax.sb
@@ -1,3 +1,4 @@
-datadir:
-- syntax_datadir
-lang: en
+book:
+  datadir:
+  - syntax_datadir
+  lang: en
diff --git a/test/test_songbook/syntax.tex.control b/test/test_songbook/syntax.tex.control
index b2147b06..e142867e 100644
--- a/test/test_songbook/syntax.tex.control
+++ b/test/test_songbook/syntax.tex.control
@@ -23,9 +23,10 @@
     ]{article}
 
 \usepackage[
-    chorded,
-diagram,
+chorded,
 pictures,
+repeatchords,
+importantdiagramonly,
 guitar,
     ]{patacrep}
 
@@ -62,6 +63,9 @@ guitar,
 \newindex{titleidx}{syntax_title}
 \newauthorindex{authidx}{syntax_auth}
 
+\authignoreword{unknown}
+\authbyword{by}
+\authsepword{and}
 
 \notenamesout{A}{B}{C}{D}{E}{F}{G}
 
diff --git a/test/test_songbook/unicode.sb b/test/test_songbook/unicode.sb
index 19392a88..9f5163c5 100644
--- a/test/test_songbook/unicode.sb
+++ b/test/test_songbook/unicode.sb
@@ -1,3 +1,4 @@
-datadir:
-- unicode_datadir
-lang: en
+book:
+  datadir:
+  - unicode_datadir
+  lang: en
diff --git a/test/test_songbook/unicode.tex.control b/test/test_songbook/unicode.tex.control
index 759a15d8..358938b6 100644
--- a/test/test_songbook/unicode.tex.control
+++ b/test/test_songbook/unicode.tex.control
@@ -23,9 +23,10 @@
     ]{article}
 
 \usepackage[
-    chorded,
-diagram,
+chorded,
 pictures,
+repeatchords,
+importantdiagramonly,
 guitar,
     ]{patacrep}
 
@@ -62,6 +63,9 @@ guitar,
 \newindex{titleidx}{unicode_title}
 \newauthorindex{authidx}{unicode_auth}
 
+\authignoreword{unknown}
+\authbyword{by}
+\authsepword{and}
 
 \notenamesout{A}{B}{C}{D}{E}{F}{G}