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diff --git a/vendor/github.com/authzed/cel-go/cel/decls.go b/vendor/github.com/authzed/cel-go/cel/decls.go
new file mode 100644
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--- /dev/null
+++ b/vendor/github.com/authzed/cel-go/cel/decls.go
@@ -0,0 +1,355 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cel
+
+import (
+	"fmt"
+
+	"github.com/authzed/cel-go/common/ast"
+	"github.com/authzed/cel-go/common/decls"
+	"github.com/authzed/cel-go/common/functions"
+	"github.com/authzed/cel-go/common/types"
+	"github.com/authzed/cel-go/common/types/ref"
+
+	exprpb "google.golang.org/genproto/googleapis/api/expr/v1alpha1"
+)
+
+// Kind indicates a CEL type's kind which is used to differentiate quickly between simple and complex types.
+type Kind = types.Kind
+
+const (
+	// DynKind represents a dynamic type. This kind only exists at type-check time.
+	DynKind Kind = types.DynKind
+
+	// AnyKind represents a google.protobuf.Any type. This kind only exists at type-check time.
+	AnyKind = types.AnyKind
+
+	// BoolKind represents a boolean type.
+	BoolKind = types.BoolKind
+
+	// BytesKind represents a bytes type.
+	BytesKind = types.BytesKind
+
+	// DoubleKind represents a double type.
+	DoubleKind = types.DoubleKind
+
+	// DurationKind represents a CEL duration type.
+	DurationKind = types.DurationKind
+
+	// IntKind represents an integer type.
+	IntKind = types.IntKind
+
+	// ListKind represents a list type.
+	ListKind = types.ListKind
+
+	// MapKind represents a map type.
+	MapKind = types.MapKind
+
+	// NullTypeKind represents a null type.
+	NullTypeKind = types.NullTypeKind
+
+	// OpaqueKind represents an abstract type which has no accessible fields.
+	OpaqueKind = types.OpaqueKind
+
+	// StringKind represents a string type.
+	StringKind = types.StringKind
+
+	// StructKind represents a structured object with typed fields.
+	StructKind = types.StructKind
+
+	// TimestampKind represents a a CEL time type.
+	TimestampKind = types.TimestampKind
+
+	// TypeKind represents the CEL type.
+	TypeKind = types.TypeKind
+
+	// TypeParamKind represents a parameterized type whose type name will be resolved at type-check time, if possible.
+	TypeParamKind = types.TypeParamKind
+
+	// UintKind represents a uint type.
+	UintKind = types.UintKind
+)
+
+var (
+	// AnyType represents the google.protobuf.Any type.
+	AnyType = types.AnyType
+	// BoolType represents the bool type.
+	BoolType = types.BoolType
+	// BytesType represents the bytes type.
+	BytesType = types.BytesType
+	// DoubleType represents the double type.
+	DoubleType = types.DoubleType
+	// DurationType represents the CEL duration type.
+	DurationType = types.DurationType
+	// DynType represents a dynamic CEL type whose type will be determined at runtime from context.
+	DynType = types.DynType
+	// IntType represents the int type.
+	IntType = types.IntType
+	// NullType represents the type of a null value.
+	NullType = types.NullType
+	// StringType represents the string type.
+	StringType = types.StringType
+	// TimestampType represents the time type.
+	TimestampType = types.TimestampType
+	// TypeType represents a CEL type
+	TypeType = types.TypeType
+	// UintType represents a uint type.
+	UintType = types.UintType
+
+	// function references for instantiating new types.
+
+	// ListType creates an instances of a list type value with the provided element type.
+	ListType = types.NewListType
+	// MapType creates an instance of a map type value with the provided key and value types.
+	MapType = types.NewMapType
+	// NullableType creates an instance of a nullable type with the provided wrapped type.
+	//
+	// Note: only primitive types are supported as wrapped types.
+	NullableType = types.NewNullableType
+	// OptionalType creates an abstract parameterized type instance corresponding to CEL's notion of optional.
+	OptionalType = types.NewOptionalType
+	// OpaqueType creates an abstract parameterized type with a given name.
+	OpaqueType = types.NewOpaqueType
+	// ObjectType creates a type references to an externally defined type, e.g. a protobuf message type.
+	ObjectType = types.NewObjectType
+	// TypeParamType creates a parameterized type instance.
+	TypeParamType = types.NewTypeParamType
+)
+
+// Type holds a reference to a runtime type with an optional type-checked set of type parameters.
+type Type = types.Type
+
+// Constant creates an instances of an identifier declaration with a variable name, type, and value.
+func Constant(name string, t *Type, v ref.Val) EnvOption {
+	return func(e *Env) (*Env, error) {
+		e.variables = append(e.variables, decls.NewConstant(name, t, v))
+		return e, nil
+	}
+}
+
+// Variable creates an instance of a variable declaration with a variable name and type.
+func Variable(name string, t *Type) EnvOption {
+	return func(e *Env) (*Env, error) {
+		e.variables = append(e.variables, decls.NewVariable(name, t))
+		return e, nil
+	}
+}
+
+// Function defines a function and overloads with optional singleton or per-overload bindings.
+//
+// Using Function is roughly equivalent to calling Declarations() to declare the function signatures
+// and Functions() to define the function bindings, if they have been defined. Specifying the
+// same function name more than once will result in the aggregation of the function overloads. If any
+// signatures conflict between the existing and new function definition an error will be raised.
+// However, if the signatures are identical and the overload ids are the same, the redefinition will
+// be considered a no-op.
+//
+// One key difference with using Function() is that each FunctionDecl provided will handle dynamic
+// dispatch based on the type-signatures of the overloads provided which means overload resolution at
+// runtime is handled out of the box rather than via a custom binding for overload resolution via
+// Functions():
+//
+// - Overloads are searched in the order they are declared
+// - Dynamic dispatch for lists and maps is limited by inspection of the list and map contents
+//
+//	at runtime. Empty lists and maps will result in a 'default dispatch'
+//
+// - In the event that a default dispatch occurs, the first overload provided is the one invoked
+//
+// If you intend to use overloads which differentiate based on the key or element type of a list or
+// map, consider using a generic function instead: e.g. func(list(T)) or func(map(K, V)) as this
+// will allow your implementation to determine how best to handle dispatch and the default behavior
+// for empty lists and maps whose contents cannot be inspected.
+//
+// For functions which use parameterized opaque types (abstract types), consider using a singleton
+// function which is capable of inspecting the contents of the type and resolving the appropriate
+// overload as CEL can only make inferences by type-name regarding such types.
+func Function(name string, opts ...FunctionOpt) EnvOption {
+	return func(e *Env) (*Env, error) {
+		fn, err := decls.NewFunction(name, opts...)
+		if err != nil {
+			return nil, err
+		}
+		if existing, found := e.functions[fn.Name()]; found {
+			fn, err = existing.Merge(fn)
+			if err != nil {
+				return nil, err
+			}
+		}
+		e.functions[fn.Name()] = fn
+		return e, nil
+	}
+}
+
+// FunctionOpt defines a functional  option for configuring a function declaration.
+type FunctionOpt = decls.FunctionOpt
+
+// SingletonUnaryBinding creates a singleton function definition to be used for all function overloads.
+//
+// Note, this approach works well if operand is expected to have a specific trait which it implements,
+// e.g. traits.ContainerType. Otherwise, prefer per-overload function bindings.
+func SingletonUnaryBinding(fn functions.UnaryOp, traits ...int) FunctionOpt {
+	return decls.SingletonUnaryBinding(fn, traits...)
+}
+
+// SingletonBinaryImpl creates a singleton function definition to be used with all function overloads.
+//
+// Note, this approach works well if operand is expected to have a specific trait which it implements,
+// e.g. traits.ContainerType. Otherwise, prefer per-overload function bindings.
+//
+// Deprecated: use SingletonBinaryBinding
+func SingletonBinaryImpl(fn functions.BinaryOp, traits ...int) FunctionOpt {
+	return decls.SingletonBinaryBinding(fn, traits...)
+}
+
+// SingletonBinaryBinding creates a singleton function definition to be used with all function overloads.
+//
+// Note, this approach works well if operand is expected to have a specific trait which it implements,
+// e.g. traits.ContainerType. Otherwise, prefer per-overload function bindings.
+func SingletonBinaryBinding(fn functions.BinaryOp, traits ...int) FunctionOpt {
+	return decls.SingletonBinaryBinding(fn, traits...)
+}
+
+// SingletonFunctionImpl creates a singleton function definition to be used with all function overloads.
+//
+// Note, this approach works well if operand is expected to have a specific trait which it implements,
+// e.g. traits.ContainerType. Otherwise, prefer per-overload function bindings.
+//
+// Deprecated: use SingletonFunctionBinding
+func SingletonFunctionImpl(fn functions.FunctionOp, traits ...int) FunctionOpt {
+	return decls.SingletonFunctionBinding(fn, traits...)
+}
+
+// SingletonFunctionBinding creates a singleton function definition to be used with all function overloads.
+//
+// Note, this approach works well if operand is expected to have a specific trait which it implements,
+// e.g. traits.ContainerType. Otherwise, prefer per-overload function bindings.
+func SingletonFunctionBinding(fn functions.FunctionOp, traits ...int) FunctionOpt {
+	return decls.SingletonFunctionBinding(fn, traits...)
+}
+
+// DisableDeclaration disables the function signatures, effectively removing them from the type-check
+// environment while preserving the runtime bindings.
+func DisableDeclaration(value bool) FunctionOpt {
+	return decls.DisableDeclaration(value)
+}
+
+// Overload defines a new global overload with an overload id, argument types, and result type. Through the
+// use of OverloadOpt options, the overload may also be configured with a binding, an operand trait, and to
+// be non-strict.
+//
+// Note: function bindings should be commonly configured with Overload instances whereas operand traits and
+// strict-ness should be rare occurrences.
+func Overload(overloadID string, args []*Type, resultType *Type, opts ...OverloadOpt) FunctionOpt {
+	return decls.Overload(overloadID, args, resultType, opts...)
+}
+
+// MemberOverload defines a new receiver-style overload (or member function) with an overload id, argument types,
+// and result type. Through the use of OverloadOpt options, the overload may also be configured with a binding,
+// an operand trait, and to be non-strict.
+//
+// Note: function bindings should be commonly configured with Overload instances whereas operand traits and
+// strict-ness should be rare occurrences.
+func MemberOverload(overloadID string, args []*Type, resultType *Type, opts ...OverloadOpt) FunctionOpt {
+	return decls.MemberOverload(overloadID, args, resultType, opts...)
+}
+
+// OverloadOpt is a functional option for configuring a function overload.
+type OverloadOpt = decls.OverloadOpt
+
+// UnaryBinding provides the implementation of a unary overload. The provided function is protected by a runtime
+// type-guard which ensures runtime type agreement between the overload signature and runtime argument types.
+func UnaryBinding(binding functions.UnaryOp) OverloadOpt {
+	return decls.UnaryBinding(binding)
+}
+
+// BinaryBinding provides the implementation of a binary overload. The provided function is protected by a runtime
+// type-guard which ensures runtime type agreement between the overload signature and runtime argument types.
+func BinaryBinding(binding functions.BinaryOp) OverloadOpt {
+	return decls.BinaryBinding(binding)
+}
+
+// FunctionBinding provides the implementation of a variadic overload. The provided function is protected by a runtime
+// type-guard which ensures runtime type agreement between the overload signature and runtime argument types.
+func FunctionBinding(binding functions.FunctionOp) OverloadOpt {
+	return decls.FunctionBinding(binding)
+}
+
+// OverloadIsNonStrict enables the function to be called with error and unknown argument values.
+//
+// Note: do not use this option unless absoluately necessary as it should be an uncommon feature.
+func OverloadIsNonStrict() OverloadOpt {
+	return decls.OverloadIsNonStrict()
+}
+
+// OverloadOperandTrait configures a set of traits which the first argument to the overload must implement in order to be
+// successfully invoked.
+func OverloadOperandTrait(trait int) OverloadOpt {
+	return decls.OverloadOperandTrait(trait)
+}
+
+// TypeToExprType converts a CEL-native type representation to a protobuf CEL Type representation.
+func TypeToExprType(t *Type) (*exprpb.Type, error) {
+	return types.TypeToExprType(t)
+}
+
+// ExprTypeToType converts a protobuf CEL type representation to a CEL-native type representation.
+func ExprTypeToType(t *exprpb.Type) (*Type, error) {
+	return types.ExprTypeToType(t)
+}
+
+// ExprDeclToDeclaration converts a protobuf CEL declaration to a CEL-native declaration, either a Variable or Function.
+func ExprDeclToDeclaration(d *exprpb.Decl) (EnvOption, error) {
+	switch d.GetDeclKind().(type) {
+	case *exprpb.Decl_Function:
+		overloads := d.GetFunction().GetOverloads()
+		opts := make([]FunctionOpt, len(overloads))
+		for i, o := range overloads {
+			args := make([]*Type, len(o.GetParams()))
+			for j, p := range o.GetParams() {
+				a, err := types.ExprTypeToType(p)
+				if err != nil {
+					return nil, err
+				}
+				args[j] = a
+			}
+			res, err := types.ExprTypeToType(o.GetResultType())
+			if err != nil {
+				return nil, err
+			}
+			if o.IsInstanceFunction {
+				opts[i] = decls.MemberOverload(o.GetOverloadId(), args, res)
+			} else {
+				opts[i] = decls.Overload(o.GetOverloadId(), args, res)
+			}
+		}
+		return Function(d.GetName(), opts...), nil
+	case *exprpb.Decl_Ident:
+		t, err := types.ExprTypeToType(d.GetIdent().GetType())
+		if err != nil {
+			return nil, err
+		}
+		if d.GetIdent().GetValue() == nil {
+			return Variable(d.GetName(), t), nil
+		}
+		val, err := ast.ConstantToVal(d.GetIdent().GetValue())
+		if err != nil {
+			return nil, err
+		}
+		return Constant(d.GetName(), t, val), nil
+	default:
+		return nil, fmt.Errorf("unsupported decl: %v", d)
+	}
+}