diff --git a/src/icmtoolchain/rule_set.py b/src/icmtoolchain/rule_set.py
new file mode 100644
index 0000000..0026b50
--- /dev/null
+++ b/src/icmtoolchain/rule_set.py
@@ -0,0 +1,94 @@
+from functools import lru_cache
+from typing import (TYPE_CHECKING, Any, Dict, MutableSequence, MutableSet,
+                    Optional, overload, override)
+
+from .utils import ensure_not_whitespace
+
+if TYPE_CHECKING:
+	from .config import Config
+
+
+class RuleSet:
+	rules: Dict[str, MutableSet[str]]
+	rule_values: MutableSet[str]
+
+	def __init__(self, prototype_set: Optional['RuleSet'] = None) -> None:
+		self.rules = dict()
+		self.rule_values = set()
+		if prototype_set:
+			self.extend_with_rules(prototype_set)
+
+	def append_rule(self, rule: str, *values: str) -> None:
+		if not rule in self.rules:
+			self.rules[rule] = set()
+		rules = self.rules[rule]
+		for value in values:
+			if value in rules:
+				continue
+			if value in self.rule_values:
+				raise ValueError(f"Rule {rule} contains value {value!r} which is already occupied by another rule!")
+			rules.add(value)
+
+	def remove_rule(self, rule: str) -> None:
+		if not rule in self.rules:
+			return
+		for value in self.rules[rule]:
+			self.rule_values.remove(value)
+		del self.rules[rule]
+
+	def extend_with_rules(self, set: 'RuleSet') -> None:
+		for rule in set.rules:
+			self.append_rule(rule, *set.rules[rule])
+
+	def rule_of(self, value: str) -> Optional[str]:
+		if not value in self.rule_values:
+			return
+		for rule in self.rules:
+			for rule_value in self.rules[rule]:
+				if value == rule_value:
+					return rule
+
+	def bisect_values(self, properties: MutableSequence[str], *values: str) -> None:
+		for value in values:
+			rule = self.rule_of(value)
+			if not rule or not rule in self.rules:
+				continue
+			for rule_value in self.rules[rule]:
+				if rule_value in properties:
+					properties.remove(rule_value)
+		for value in values:
+			properties.append(value)
+
+	def remove_values(self, properties: MutableSequence[str], rule: str) -> None:
+		if not rule in self.rules:
+			return
+		for value in self.rules[rule]:
+			if value in properties:
+				properties.remove(value)
+
+	def is_relevant(self, properties: MutableSequence[str], value_set: str, allow_unresolved_properties: bool = True) -> bool:
+		if not ensure_not_whitespace(value_set) or value_set == "*":
+			return True
+		values = value_set.split("-")
+		for value in values:
+			if not value in properties:
+				return False
+			if not allow_unresolved_properties and not value in self.rule_values:
+				# Most likely a console property that cannot be checked here.
+				return False
+		return True
+
+TOOLCHAIN_RULE_SET = RuleSet()
+TOOLCHAIN_RULE_SET.append_rule("package_type", "develop", "release")
+TOOLCHAIN_RULE_SET.append_rule("native_architecture", "arm", "arm64", "x86", "x86_64")
+
+
+@lru_cache(maxsize=4096)
+def get_config_rule_set(type: Optional[type['Config']]):
+	if not type:
+		if not TYPE_CHECKING:
+			from .config import Config
+		type = Config
+	class RuleSetConfig(type):
+		pass
+	return RuleSetConfig