diff --git a/.gitignore b/.gitignore
index 9a52e5b..07ddefb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,4 @@
+*~
+*.pyc
+dist/
 pyCOREPOS.egg-info/
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 20d31e0..2c26baa 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,129 @@ All notable changes to pyCOREPOS will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
+## v0.5.1 (2025-02-20)
+
+### Fix
+
+- add `Product.default_vendor_item` convenience property
+
+## v0.5.0 (2025-02-01)
+
+### Feat
+
+- use true column names for transaction data models
+
+### Fix
+
+- define common base schema for Product model
+- add `Parameter` model for lane_op
+- add model for lane_trans `LocalTrans`
+
+## v0.4.0 (2025-01-24)
+
+### Feat
+
+- add common base class for `dtransactions` and similar models
+
+### Fix
+
+- add `Employee` model for lane_op
+- fix ordering of name columns for MemberInfo
+
+## v0.3.5 (2025-01-15)
+
+### Fix
+
+- add workaround to avoid missing schema columns
+
+## v0.3.4 (2025-01-15)
+
+### Fix
+
+- misc. cleanup for sales batch models
+- add more enums for batch discount type, editor UI
+
+## v0.3.3 (2025-01-13)
+
+### Fix
+
+- remove `autoincrement` option for composite PK fields
+
+## v0.3.2 (2025-01-11)
+
+### Fix
+
+- add base class for all transaction tables, views
+- add `MemberType.ignore_sales` column
+- add model for `MasterSuperDepartment`
+
+## v0.3.1 (2024-12-17)
+
+### Fix
+
+- add `wicable`, `active` columns for Department model
+
+## v0.3.0 (2024-08-06)
+
+### Feat
+
+- add model for `MemberContactPreference` (`op.memContactPrefs`)
+- add model for `CustomReceiptLine` (`op.customReceipt`)
+
+## v0.2.1 (2024-07-04)
+
+### Fix
+
+- add API methods, `get_employees()` and `get_employee()`
+- remove `Change` data model
+- remove dependency for `six` package
+
+## v0.2.0 (2024-06-10)
+
+### Feat
+
+- switch from setup.cfg to pyproject.toml + hatchling
+
+## [0.1.20] - 2024-05-29
+### Changed
+- Add enum for CORE (Office) DB types.
+
+## [0.1.19] - 2023-11-01
+### Changed
+- Fix data types for tax, voided in `dtransactions`.
+- Fix synonym for `dtransactions.tax`.
+
+## [0.1.18] - 2023-10-12
+### Changed
+- Fix the `Department.tax_rate` relationship.
+- Let `MemberInfo.dates` be an object, not a list.
+
+## [0.1.17] - 2023-10-07
+### Changed
+- Rename module to `corepos.db.office_arch`.
+
+## [0.1.16] - 2023-09-15
+### Changed
+- Add model for `office_op.Tender`.
+
+## [0.1.15] - 2023-09-13
+### Changed
+- Add model for `CustomerNotifications` table.
+
+## [0.1.14] - 2023-09-07
+### Changed
+- Tweak primary key for StockPurchase model.
+
+## [0.1.13] - 2023-09-02
+### Changed
+- Add models for StockPurchase and EquityLiveBalance.
+
+## [0.1.12] - 2023-06-12
+### Changed
+- Add `get_member_types()` method for CORE API.
+- Rename model for `custdata` to `CustomerClassic`.
+- Add note about `meminfo.email_2` field, aka. "alt. phone".
+
 ## [0.1.11] - 2023-06-02
 ### Changed
 - Add support for htdigest auth when using CORE webservices API.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..dd69797
--- /dev/null
+++ b/README.md
@@ -0,0 +1,5 @@
+
+# pyCOREPOS
+
+A Python interface to the [CORE POS](https://github.com/CORE-POS)
+system.
diff --git a/README.rst b/README.rst
deleted file mode 100644
index 0b34d2f..0000000
--- a/README.rst
+++ /dev/null
@@ -1,7 +0,0 @@
-
-pyCOREPOS
-=========
-
-A Python interface to the `CORE POS`_ system.
-
-.. _CORE POS:  https://github.com/CORE-POS
diff --git a/corepos/_version.py b/corepos/_version.py
index 862eaaa..555fee3 100644
--- a/corepos/_version.py
+++ b/corepos/_version.py
@@ -1,3 +1,6 @@
 # -*- coding: utf-8; -*-
 
-__version__ = '0.1.11'
+from importlib.metadata import version
+
+
+__version__ = version('pyCOREPOS')
diff --git a/corepos/api.py b/corepos/api.py
index c93ff9d..a24b906 100644
--- a/corepos/api.py
+++ b/corepos/api.py
@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  pyCOREPOS -- Python Interface to CORE POS
-#  Copyright © 2018-2023 Lance Edgar
+#  Copyright © 2018-2024 Lance Edgar
 #
 #  This file is part of pyCOREPOS.
 #
@@ -132,6 +132,22 @@ class CoreWebAPI(object):
         assert set(js['result'].keys()) == set(['result'])
         return js['result']['result']
 
+    def get_member_types(self):
+        """
+        Fetch all Member Type records from CORE.
+
+        :returns: A (potentially empty) list of member type dict records.
+        """
+        params = {
+            'entity': 'Memtype',
+            'submethod': 'get',
+            'columns': {},
+        }
+
+        response = self.post(params)
+        result = self.parse_response(response)
+        return [json.loads(rec) for rec in result]
+
     def get_members(self):
         """
         Fetch all Member records from CORE.
@@ -182,6 +198,40 @@ class CoreWebAPI(object):
         if result:
             return result
 
+    def get_employees(self, **columns):
+        """
+        Fetch some or all of Employee records from CORE.
+
+        :returns: A (potentially empty) list of employee dict records.
+        """
+        params = {
+            'entity': 'Employees',
+            'submethod': 'get',
+            'columns': columns,
+        }
+        response = self.post(params)
+        result = self.parse_response(response)
+        return [json.loads(rec) for rec in result]
+
+    def get_employee(self, emp_no, **columns):
+        """
+        Fetch an existing Employee record from CORE.
+
+        :returns: Either a employee dict record, or ``None``.
+        """
+        columns['emp_no'] = emp_no
+        params = {
+            'entity': 'Employees',
+            'submethod': 'get',
+            'columns': columns,
+        }
+        response = self.post(params)
+        result = self.parse_response(response)
+        if result:
+            if len(result) > 1:
+                log.warning("CORE API returned %s employee results", len(result))
+            return json.loads(result[0])
+
     def get_stores(self, **columns):
         """
         Fetch some or all of Store records from CORE.
diff --git a/corepos/db/common/__init__.py b/corepos/db/common/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/corepos/db/common/op.py b/corepos/db/common/op.py
new file mode 100644
index 0000000..30ecc1c
--- /dev/null
+++ b/corepos/db/common/op.py
@@ -0,0 +1,173 @@
+# -*- coding: utf-8; -*-
+################################################################################
+#
+#  pyCOREPOS -- Python Interface to CORE POS
+#  Copyright © 2018-2025 Lance Edgar
+#
+#  This file is part of pyCOREPOS.
+#
+#  pyCOREPOS is free software: you can redistribute it and/or modify it under
+#  the terms of the GNU General Public License as published by the Free
+#  Software Foundation, either version 3 of the License, or (at your option)
+#  any later version.
+#
+#  pyCOREPOS is distributed in the hope that it will be useful, but WITHOUT ANY
+#  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+#  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+#  details.
+#
+#  You should have received a copy of the GNU General Public License along with
+#  pyCOREPOS.  If not, see <http://www.gnu.org/licenses/>.
+#
+################################################################################
+"""
+Common schema for operational data models
+"""
+
+import sqlalchemy as sa
+
+
+class ParameterBase:
+    """
+    Base class for Parameter models, shared by Office + Lane.
+    """
+    store_id = sa.Column(sa.SmallInteger(), primary_key=True, nullable=False)
+
+    lane_id = sa.Column(sa.SmallInteger(), primary_key=True, nullable=False)
+
+    param_key = sa.Column(sa.String(length=100), primary_key=True, nullable=False)
+
+    param_value = sa.Column(sa.String(length=255), nullable=True)
+
+    is_array = sa.Column(sa.Boolean(), nullable=True)
+
+    def __str__(self):
+        return f"{self.store_id}-{self.lane_id} {self.param_key}"
+
+
+class EmployeeBase:
+    """
+    Base class for Employee models, shared by Office + Lane.
+    """
+    number = sa.Column('emp_no', sa.SmallInteger(), nullable=False,
+                       primary_key=True, autoincrement=False)
+
+    cashier_password = sa.Column('CashierPassword', sa.String(length=50), nullable=True)
+
+    admin_password = sa.Column('AdminPassword', sa.String(length=50), nullable=True)
+
+    first_name = sa.Column('FirstName', sa.String(length=255), nullable=True)
+
+    last_name = sa.Column('LastName', sa.String(length=255), nullable=True)
+
+    job_title = sa.Column('JobTitle', sa.String(length=255), nullable=True)
+
+    active = sa.Column('EmpActive', sa.Boolean(), nullable=True)
+
+    frontend_security = sa.Column('frontendsecurity', sa.SmallInteger(), nullable=True)
+
+    backend_security = sa.Column('backendsecurity', sa.SmallInteger(), nullable=True)
+
+    birth_date = sa.Column('birthdate', sa.DateTime(), nullable=True)
+
+    def __str__(self):
+        return ' '.join([self.first_name or '', self.last_name or '']).strip()
+
+
+class ProductBase:
+    """
+    Base class for Product models, shared by Office + Lane.
+    """
+    id = sa.Column(sa.Integer(), nullable=False, primary_key=True, autoincrement=True)
+
+    upc = sa.Column(sa.String(length=13), nullable=True)
+
+    description = sa.Column(sa.String(length=30), nullable=True)
+
+    brand = sa.Column(sa.String(length=30), nullable=True)
+
+    formatted_name = sa.Column(sa.String(length=30), nullable=True)
+
+    normal_price = sa.Column(sa.Float(), nullable=True)
+
+    price_method = sa.Column('pricemethod', sa.SmallInteger(), nullable=True)
+
+    group_price = sa.Column('groupprice', sa.Float(), nullable=True)
+
+    quantity = sa.Column(sa.SmallInteger(), nullable=True)
+
+    special_price = sa.Column(sa.Float(), nullable=True)
+
+    special_price_method = sa.Column('specialpricemethod', sa.SmallInteger(), nullable=True)
+
+    special_group_price = sa.Column('specialgroupprice', sa.Float(), nullable=True)
+
+    special_quantity = sa.Column('specialquantity', sa.SmallInteger(), nullable=True)
+
+    special_limit = sa.Column(sa.SmallInteger(), nullable=True)
+
+    start_date = sa.Column(sa.DateTime(), nullable=True)
+
+    end_date = sa.Column(sa.DateTime(), nullable=True)
+
+    department_number = sa.Column('department', sa.SmallInteger(), nullable=True)
+
+    size = sa.Column(sa.String(length=9), nullable=True)
+
+    tax_rate_id = sa.Column('tax', sa.SmallInteger(), nullable=True)
+
+    foodstamp = sa.Column(sa.Boolean(), nullable=True)
+
+    scale = sa.Column(sa.Boolean(), nullable=True)
+
+    scale_price = sa.Column('scaleprice', sa.Float(), nullable=True)
+
+    mix_match_code = sa.Column('mixmatchcode', sa.String(length=13), nullable=True)
+
+    created = sa.Column(sa.DateTime(), nullable=True)
+
+    modified = sa.Column(sa.DateTime(), nullable=True)
+
+    tare_weight = sa.Column('tareweight', sa.Float(), nullable=True)
+
+    discount = sa.Column(sa.SmallInteger(), nullable=True)
+
+    discount_type = sa.Column('discounttype', sa.SmallInteger(), nullable=True)
+
+    line_item_discountable = sa.Column(sa.Boolean(), nullable=True)
+
+    unit_of_measure = sa.Column('unitofmeasure', sa.String(length=15), nullable=True)
+
+    wicable = sa.Column(sa.SmallInteger(), nullable=True)
+
+    quantity_enforced = sa.Column('qttyEnforced', sa.Boolean(), nullable=True)
+
+    id_enforced = sa.Column('idEnforced', sa.SmallInteger(), nullable=True)
+
+    cost = sa.Column(sa.Float(), nullable=True)
+
+    special_cost = sa.Column(sa.Float(), nullable=True)
+
+    received_cost = sa.Column(sa.Float(), nullable=True)
+
+    in_use = sa.Column('inUse', sa.Boolean(), nullable=True)
+
+    numflag = sa.Column(sa.Integer(), nullable=True)
+
+    subdepartment_number = sa.Column('subdept', sa.SmallInteger(), nullable=True)
+
+    deposit = sa.Column(sa.Float(), nullable=True)
+
+    local = sa.Column(sa.Integer(), nullable=True, default=0)
+
+    store_id = sa.Column(sa.SmallInteger(), nullable=True)
+
+    default_vendor_id = sa.Column(sa.Integer(), nullable=True)
+
+    current_origin_id = sa.Column(sa.Integer(), nullable=True)
+
+    auto_par = sa.Column(sa.Float(), nullable=True, default=0)
+
+    price_rule_id = sa.Column(sa.Integer(), nullable=True, default=0)
+
+    last_sold = sa.Column(sa.DateTime(), nullable=True)
diff --git a/corepos/db/common/trans.py b/corepos/db/common/trans.py
new file mode 100644
index 0000000..9ec5601
--- /dev/null
+++ b/corepos/db/common/trans.py
@@ -0,0 +1,114 @@
+# -*- coding: utf-8; -*-
+################################################################################
+#
+#  pyCOREPOS -- Python Interface to CORE POS
+#  Copyright © 2018-2025 Lance Edgar
+#
+#  This file is part of pyCOREPOS.
+#
+#  pyCOREPOS is free software: you can redistribute it and/or modify it under
+#  the terms of the GNU General Public License as published by the Free
+#  Software Foundation, either version 3 of the License, or (at your option)
+#  any later version.
+#
+#  pyCOREPOS is distributed in the hope that it will be useful, but WITHOUT ANY
+#  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+#  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+#  details.
+#
+#  You should have received a copy of the GNU General Public License along with
+#  pyCOREPOS.  If not, see <http://www.gnu.org/licenses/>.
+#
+################################################################################
+"""
+Common schema for transaction data models
+"""
+
+import sqlalchemy as sa
+from sqlalchemy import orm
+from sqlalchemy.ext.declarative import declared_attr
+
+
+class TransactionDetailBase:
+    """
+    Base class for POS transaction detail models, shared by Office +
+    Lane.
+    """
+
+    # register
+    register_no = sa.Column(sa.Integer(), nullable=True)
+
+    # txn
+    trans_id = sa.Column(sa.Integer(), nullable=True)
+    trans_no = sa.Column(sa.Integer(), nullable=True)
+    trans_type = sa.Column(sa.String(length=1), nullable=True)
+    trans_subtype = sa.Column(sa.String(length=2), nullable=True)
+    trans_status = sa.Column(sa.String(length=1), nullable=True)
+
+    # cashier
+    emp_no = sa.Column(sa.Integer(), nullable=True)
+
+    # customer
+    card_no = sa.Column(sa.Integer(), nullable=True)
+    memType = sa.Column(sa.Integer(), nullable=True)
+    staff = sa.Column(sa.Boolean(), nullable=True)
+
+    ##############################
+    # remainder is "line item" ...
+    ##############################
+
+    upc = sa.Column(sa.String(length=13), nullable=True)
+
+    department = sa.Column(sa.Integer(), nullable=True)
+
+    description = sa.Column(sa.String(length=30), nullable=True)
+
+    quantity = sa.Column(sa.Float(), nullable=True)
+
+    scale = sa.Column(sa.Boolean(), nullable=True, default=False)
+
+    cost = sa.Column(sa.Numeric(precision=10, scale=2), nullable=True)
+
+    unitPrice = sa.Column(sa.Numeric(precision=10, scale=2), nullable=True)
+
+    total = sa.Column(sa.Numeric(precision=10, scale=2), nullable=True)
+
+    regPrice = sa.Column(sa.Numeric(precision=10, scale=2), nullable=True)
+
+    tax = sa.Column(sa.SmallInteger(), nullable=True)
+
+    foodstamp = sa.Column(sa.Boolean(), nullable=True)
+
+    discount = sa.Column(sa.Numeric(precision=10, scale=2), nullable=True)
+
+    memDiscount = sa.Column(sa.Numeric(precision=10, scale=2), nullable=True)
+
+    discountable = sa.Column(sa.Boolean(), nullable=True)
+
+    discounttype = sa.Column(sa.Integer(), nullable=True)
+
+    voided = sa.Column(sa.Integer(), nullable=True)
+
+    percentDiscount = sa.Column(sa.Integer(), nullable=True)
+
+    ItemQtty = sa.Column(sa.Float(), nullable=True)
+
+    volDiscType = sa.Column(sa.Integer(), nullable=True)
+
+    volume = sa.Column(sa.Integer(), nullable=True)
+
+    VolSpecial = sa.Column(sa.Numeric(precision=10, scale=2), nullable=True)
+
+    mixMatch = sa.Column(sa.String(length=13), nullable=True)
+
+    matched = sa.Column(sa.Boolean(), nullable=True)
+
+    numflag = sa.Column(sa.Integer(), nullable=True, default=0)
+
+    charflag = sa.Column(sa.String(length=2), nullable=True)
+
+    def __str__(self):
+        txnid = '-'.join([str(val) for val in [self.register_no,
+                                               self.trans_no,
+                                               self.trans_id]])
+        return f"{txnid} {self.description or ''}"
diff --git a/corepos/db/lane_op/model.py b/corepos/db/lane_op/model.py
index 1c687ab..456b1b8 100644
--- a/corepos/db/lane_op/model.py
+++ b/corepos/db/lane_op/model.py
@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  pyCOREPOS -- Python Interface to CORE POS
-#  Copyright © 2018-2023 Lance Edgar
+#  Copyright © 2018-2025 Lance Edgar
 #
 #  This file is part of pyCOREPOS.
 #
@@ -27,10 +27,26 @@ Data model for CORE POS "lane_op" DB
 import sqlalchemy as sa
 from sqlalchemy import orm
 
+from corepos.db.common import op as common
+
 
 Base = orm.declarative_base()
 
 
+class Parameter(common.ParameterBase, Base):
+    """
+    Data model for ``parameters`` table.
+    """
+    __tablename__ = 'parameters'
+
+
+class Employee(common.EmployeeBase, Base):
+    """
+    Data model for ``employees`` table.
+    """
+    __tablename__ = 'employees'
+
+
 class Department(Base):
     """
     Represents a department within the organization.
@@ -72,144 +88,14 @@ class Department(Base):
         return self.name or ""
 
 
-class Product(Base):
+class Product(common.ProductBase, Base):
     """
-    Represents a product, purchased and/or sold by the organization.
+    Data model for ``products`` table.
     """
     __tablename__ = 'products'
-    # __table_args__ = (
-    #     sa.ForeignKeyConstraint(['department'], ['departments.dept_no']),
-    #     sa.ForeignKeyConstraint(['subdept'], ['subdepts.subdept_no']),
-    #     sa.ForeignKeyConstraint(['tax'], ['taxrates.id']),
-    # )
-
-    id = sa.Column(sa.Integer(), nullable=False, 
-                   primary_key=True, autoincrement=True)
-
-    upc = sa.Column(sa.String(length=13), nullable=True)
-
-    description = sa.Column(sa.String(length=30), nullable=True)
-
-    brand = sa.Column(sa.String(length=30), nullable=True)
-
-    formatted_name = sa.Column(sa.String(length=30), nullable=True)
-
-    normal_price = sa.Column(sa.Float(), nullable=True)
-
-    price_method = sa.Column('pricemethod', sa.SmallInteger(), nullable=True)
-
-    group_price = sa.Column('groupprice', sa.Float(), nullable=True)
-
-    quantity = sa.Column(sa.SmallInteger(), nullable=True)
-
-    special_price = sa.Column(sa.Float(), nullable=True)
-
-    special_price_method = sa.Column('specialpricemethod', sa.SmallInteger(), nullable=True)
-
-    special_group_price = sa.Column('specialgroupprice', sa.Float(), nullable=True)
-
-    special_quantity = sa.Column('specialquantity', sa.SmallInteger(), nullable=True)
-
-    special_limit = sa.Column(sa.SmallInteger(), nullable=True)
-
-    start_date = sa.Column(sa.DateTime(), nullable=True)
-
-    end_date = sa.Column(sa.DateTime(), nullable=True)
-
-    department_number = sa.Column('department', sa.SmallInteger(), nullable=True)
-    # department = orm.relationship(
-    #     Department,
-    #     primaryjoin=Department.number == department_number,
-    #     foreign_keys=[department_number],
-    #     doc="""
-    #     Reference to the :class:`Department` to which the product belongs.
-    #     """)
-
-    size = sa.Column(sa.String(length=9), nullable=True)
-
-    tax_rate_id = sa.Column('tax', sa.SmallInteger(), nullable=True)
-    # tax_rate = orm.relationship(TaxRate)
-
-    foodstamp = sa.Column(sa.Boolean(), nullable=True)
-
-    scale = sa.Column(sa.Boolean(), nullable=True)
-
-    scale_price = sa.Column('scaleprice', sa.Float(), nullable=True)
-
-    mix_match_code = sa.Column('mixmatchcode', sa.String(length=13), nullable=True)
-
-    created = sa.Column(sa.DateTime(), nullable=True)
-
-    modified = sa.Column(sa.DateTime(), nullable=True)
-
-    # TODO: what to do about this 'replaces' thing?
-    # 'batchID'=>array('type'=>'TINYINT', 'replaces'=>'advertised'),
-    # batch_id = sa.Column('batchID', sa.SmallInteger(), nullable=True)
-    # advertised = sa.Column(sa.Boolean(), nullable=True)
-
-    tare_weight = sa.Column('tareweight', sa.Float(), nullable=True)
-
-    discount = sa.Column(sa.SmallInteger(), nullable=True)
-
-    discount_type = sa.Column('discounttype', sa.SmallInteger(), nullable=True)
-
-    line_item_discountable = sa.Column(sa.Boolean(), nullable=True)
-
-    unit_of_measure = sa.Column('unitofmeasure', sa.String(length=15), nullable=True)
-
-    wicable = sa.Column(sa.SmallInteger(), nullable=True)
-
-    quantity_enforced = sa.Column('qttyEnforced', sa.Boolean(), nullable=True)
-
-    id_enforced = sa.Column('idEnforced', sa.SmallInteger(), nullable=True)
-
-    cost = sa.Column(sa.Float(), nullable=True)
-
-    special_cost = sa.Column(sa.Float(), nullable=True)
-
-    received_cost = sa.Column(sa.Float(), nullable=True)
-
-    in_use = sa.Column('inUse', sa.Boolean(), nullable=True)
-
-    flags = sa.Column('numflag', sa.Integer(), nullable=True)
-
-    subdepartment_number = sa.Column('subdept', sa.SmallInteger(), nullable=True)
-    # subdepartment = orm.relationship(
-    #     Subdepartment,
-    #     primaryjoin=Subdepartment.number == subdepartment_number,
-    #     foreign_keys=[subdepartment_number],
-    #     doc="""
-    #     Reference to the :class:`Subdepartment` to which the product belongs.
-    #     """)
-
-    deposit = sa.Column(sa.Float(), nullable=True)
-
-    local = sa.Column(sa.Integer(), nullable=True,
-                      default=0) # TODO: do we want a default here?
-
-    store_id = sa.Column(sa.SmallInteger(), nullable=True)
-
-    default_vendor_id = sa.Column(sa.Integer(), nullable=True)
-    # default_vendor = orm.relationship(
-    #     Vendor,
-    #     primaryjoin=Vendor.id == default_vendor_id,
-    #     foreign_keys=[default_vendor_id],
-    #     doc="""
-    #     Reference to the default :class:`Vendor` from which the product is obtained.
-    #     """)
-
-    current_origin_id = sa.Column(sa.Integer(), nullable=True)
-
-    auto_par = sa.Column(sa.Float(), nullable=True,
-                         default=0) # TODO: do we want a default here?
-
-    price_rule_id = sa.Column(sa.Integer(), nullable=True)
-
-    # TODO: some older DB's might not have this?  guess we'll see
-    last_sold = sa.Column(sa.DateTime(), nullable=True)
 
 
-class CustData(Base):
+class CustomerClassic(Base):
     """
     Represents a customer of the organization.
 
@@ -275,3 +161,7 @@ class CustData(Base):
 
     def __str__(self):
         return "{} {}".format(self.first_name or '', self.last_name or '').strip()
+
+
+# TODO: deprecate / remove this
+CustData = CustomerClassic
diff --git a/corepos/db/lane_trans/__init__.py b/corepos/db/lane_trans/__init__.py
new file mode 100644
index 0000000..8e8c706
--- /dev/null
+++ b/corepos/db/lane_trans/__init__.py
@@ -0,0 +1,30 @@
+# -*- coding: utf-8; -*-
+################################################################################
+#
+#  pyCOREPOS -- Python Interface to CORE POS
+#  Copyright © 2018-2025 Lance Edgar
+#
+#  This file is part of pyCOREPOS.
+#
+#  pyCOREPOS is free software: you can redistribute it and/or modify it under
+#  the terms of the GNU General Public License as published by the Free
+#  Software Foundation, either version 3 of the License, or (at your option)
+#  any later version.
+#
+#  pyCOREPOS is distributed in the hope that it will be useful, but WITHOUT ANY
+#  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+#  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+#  details.
+#
+#  You should have received a copy of the GNU General Public License along with
+#  pyCOREPOS.  If not, see <http://www.gnu.org/licenses/>.
+#
+################################################################################
+"""
+Lane Transaction Database
+"""
+
+from sqlalchemy import orm
+
+
+Session = orm.sessionmaker()
diff --git a/corepos/db/lane_trans/model.py b/corepos/db/lane_trans/model.py
new file mode 100644
index 0000000..f2245f5
--- /dev/null
+++ b/corepos/db/lane_trans/model.py
@@ -0,0 +1,79 @@
+# -*- coding: utf-8; -*-
+################################################################################
+#
+#  pyCOREPOS -- Python Interface to CORE POS
+#  Copyright © 2018-2025 Lance Edgar
+#
+#  This file is part of pyCOREPOS.
+#
+#  pyCOREPOS is free software: you can redistribute it and/or modify it under
+#  the terms of the GNU General Public License as published by the Free
+#  Software Foundation, either version 3 of the License, or (at your option)
+#  any later version.
+#
+#  pyCOREPOS is distributed in the hope that it will be useful, but WITHOUT ANY
+#  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+#  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+#  details.
+#
+#  You should have received a copy of the GNU General Public License along with
+#  pyCOREPOS.  If not, see <http://www.gnu.org/licenses/>.
+#
+################################################################################
+"""
+Data model for CORE POS "lane_trans" DB
+"""
+
+import sqlalchemy as sa
+from sqlalchemy import orm
+from sqlalchemy.ext.declarative import declared_attr
+
+from corepos.db.common import trans as common
+
+
+Base = orm.declarative_base()
+
+
+class DTransactionBase(common.TransactionDetailBase):
+    """
+    Base class for ``dtransactions`` and similar models.
+    """
+    pos_row_id = sa.Column(sa.Integer(), primary_key=True, nullable=False)
+
+    store_id = sa.Column(sa.Integer(), nullable=True, default=0)
+    date_time = sa.Column('datetime', sa.DateTime(), nullable=True)
+
+
+class DTransaction(DTransactionBase, Base):
+    """
+    Data model for ``dtransactions`` table.
+    """
+    __tablename__ = 'dtransactions'
+
+
+class LocalTransBase(common.TransactionDetailBase):
+    """
+    Base class for ``localtrans`` and similar models.
+    """
+
+    @declared_attr
+    def __table_args__(self):
+        return (
+            sa.PrimaryKeyConstraint('trans_id'),
+        )
+
+    date_time = sa.Column('datetime', sa.DateTime(), nullable=True)
+
+
+class LocalTrans(LocalTransBase, Base):
+    """
+    Data model for ``localtrans`` table.
+    """
+    __tablename__ = 'localtrans'
+
+
+class LocalTempTrans(LocalTransBase, Base):
+    """
+    Data model for ``localtemptrans`` table.
+    """
+    __tablename__ = 'localtemptrans'
diff --git a/setup.py b/corepos/db/office_arch/__init__.py
similarity index 89%
rename from setup.py
rename to corepos/db/office_arch/__init__.py
index a02ef90..70292e9 100644
--- a/setup.py
+++ b/corepos/db/office_arch/__init__.py
@@ -20,7 +20,11 @@
 #  pyCOREPOS.  If not, see <http://www.gnu.org/licenses/>.
 #
 ################################################################################
+"""
+"Archive" Transaction Database Interface
+"""
 
-from setuptools import setup
+from sqlalchemy import orm
 
-setup()
+
+Session = orm.sessionmaker()
diff --git a/corepos/db/office_arch/model.py b/corepos/db/office_arch/model.py
new file mode 100644
index 0000000..bc5838f
--- /dev/null
+++ b/corepos/db/office_arch/model.py
@@ -0,0 +1,63 @@
+# -*- coding: utf-8; -*-
+################################################################################
+#
+#  pyCOREPOS -- Python Interface to CORE POS
+#  Copyright © 2018-2025 Lance Edgar
+#
+#  This file is part of pyCOREPOS.
+#
+#  pyCOREPOS is free software: you can redistribute it and/or modify it under
+#  the terms of the GNU General Public License as published by the Free
+#  Software Foundation, either version 3 of the License, or (at your option)
+#  any later version.
+#
+#  pyCOREPOS is distributed in the hope that it will be useful, but WITHOUT ANY
+#  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+#  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+#  details.
+#
+#  You should have received a copy of the GNU General Public License along with
+#  pyCOREPOS.  If not, see <http://www.gnu.org/licenses/>.
+#
+################################################################################
+"""
+CORE Office "arch" data model
+"""
+
+import sqlalchemy as sa
+from sqlalchemy import orm
+
+from corepos.db.common import trans as common
+from corepos.db.office_trans.model import DTransactionBase
+
+
+Base = orm.declarative_base()
+
+
+class BigArchive(DTransactionBase, Base):
+    """
+    Data model for ``bigArchive`` table.
+    """
+    __tablename__ = 'bigArchive'
+
+
+# TODO: deprecate / remove this
+TransactionDetail = BigArchive
+
+
+class DLogBase(common.TransactionDetailBase):
+    """
+    Base class for ``dlogBig`` and similar models.
+    """
+    store_row_id = sa.Column(sa.Integer(), primary_key=True, nullable=False)
+
+    store_id = sa.Column(sa.Integer(), nullable=True, default=0)
+    pos_row_id = sa.Column(sa.Integer(), nullable=True)
+    date_time = sa.Column('tdate', sa.DateTime(), nullable=True)
+
+
+class DLogBig(DLogBase, Base):
+    """
+    Data model for ``dlogBig`` view.
+    """
+    __tablename__ = 'dlogBig'
diff --git a/corepos/db/office_op/model.py b/corepos/db/office_op/model.py
index 132fd33..60ad478 100644
--- a/corepos/db/office_op/model.py
+++ b/corepos/db/office_op/model.py
@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  pyCOREPOS -- Python Interface to CORE POS
-#  Copyright © 2018-2023 Lance Edgar
+#  Copyright © 2018-2025 Lance Edgar
 #
 #  This file is part of pyCOREPOS.
 #
@@ -31,6 +31,8 @@ import sqlalchemy as sa
 from sqlalchemy import orm
 from sqlalchemy.ext.associationproxy import association_proxy
 
+from corepos.db.common import op as common
+
 
 log = logging.getLogger(__name__)
 
@@ -54,42 +56,12 @@ class StringableDateTime(sa.TypeDecorator):
         raise NotImplementedError
 
 
-class Change(Base):
+class Parameter(common.ParameterBase, Base):
     """
-    Represents a changed (or deleted) record, which is pending synchronization
-    to another system(s).
-
-    .. note::
-       This table may or may not be installed to a given CORE Office Op DB.  Its
-       presence is required if Rattail datasync needs to "watch" the DB.
-    """
-    __tablename__ = 'datasync_changes'
-
-    id = sa.Column(sa.Integer(), nullable=False, primary_key=True)
-    object_type = sa.Column(sa.String(length=255), nullable=False)
-    object_key = sa.Column(sa.String(length=255), nullable=False)
-    deleted = sa.Column(sa.Boolean(), nullable=False, default=False)
-
-
-class Parameter(Base):
-    """
-    Represents a "parameter" value.
+    Data model for ``parameters`` table.
     """
     __tablename__ = 'parameters'
 
-    store_id = sa.Column(sa.SmallInteger(), primary_key=True, nullable=False)
-
-    lane_id = sa.Column(sa.SmallInteger(), primary_key=True, nullable=False)
-
-    param_key = sa.Column(sa.String(length=100), primary_key=True, nullable=False)
-
-    param_value = sa.Column(sa.String(length=255), nullable=True)
-
-    is_array = sa.Column(sa.Boolean(), nullable=True)
-
-    def __str__(self):
-        return "{}-{} {}".format(self.store_id, self.lane_id, self.param_key)
-
 
 class TableSyncRule(Base):
     """
@@ -97,7 +69,9 @@ class TableSyncRule(Base):
     """
     __tablename__ = 'TableSyncRules'
 
-    id = sa.Column('tableSyncRuleID', sa.Integer(), nullable=False, primary_key=True, autoincrement=True)
+    # nb. this should be autoincrement, but we can't do that
+    # automatically via sqlalchemy when PK is composite
+    id = sa.Column('tableSyncRuleID', sa.Integer(), nullable=False, primary_key=True)
 
     table_name = sa.Column('tableName', sa.String(length=255), nullable=False, primary_key=True)
 
@@ -186,6 +160,25 @@ class Store(Base):
         return self.description or ""
 
 
+class MasterSuperDepartment(Base):
+    """
+    A department may belong to more than one superdepartment, but has
+    one "master" superdepartment.  This avoids duplicating rows in
+    some reports.  By convention, a department's "master"
+    superdepartment is the one with the lowest superID.
+    """
+    __tablename__ = 'MasterSuperDepts'
+
+    super_id = sa.Column('superID', sa.Integer(), primary_key=True, autoincrement=False, nullable=False)
+
+    department_id = sa.Column('dept_ID', sa.Integer(), primary_key=True, autoincrement=False, nullable=False)
+
+    super_name = sa.Column(sa.String(length=50), nullable=True)
+
+    def __str__(self):
+        return self.super_name or ""
+
+
 class SuperDepartment(Base):
     """
     Represents a "super" (parent/child) department mapping.
@@ -225,15 +218,25 @@ class Department(Base):
     Represents a department within the organization.
     """
     __tablename__ = 'departments'
+    __table_args__ = (
+        sa.ForeignKeyConstraint(['dept_tax'], ['taxrates.id']),
+    )
 
     number = sa.Column('dept_no', sa.SmallInteger(), primary_key=True, autoincrement=False, nullable=False)
 
     name = sa.Column('dept_name', sa.String(length=30), nullable=True)
 
-    tax = sa.Column('dept_tax', sa.Boolean(), nullable=True)
+    tax_rate_id = sa.Column('dept_tax', sa.SmallInteger(), nullable=True)
+    tax_rate = orm.relationship('TaxRate')
+    # TODO: deprecate / remove this
+    tax = orm.synonym('tax_rate_id')
 
     food_stampable = sa.Column('dept_fs', sa.Boolean(), nullable=True)
 
+    wicable = sa.Column('dept_wicable', sa.SmallInteger(), nullable=True)
+
+    active = sa.Column(sa.Boolean(), default=True)
+
     limit = sa.Column('dept_limit', sa.Float(), nullable=True)
 
     minimum = sa.Column('dept_minimum', sa.Float(), nullable=True)
@@ -533,7 +536,7 @@ class Origin(Base):
         return self.name or self.short_name or ""
 
 
-class Product(Base):
+class Product(common.ProductBase, Base):
     """
     Represents a product, purchased and/or sold by the organization.
     """
@@ -544,125 +547,68 @@ class Product(Base):
         sa.ForeignKeyConstraint(['tax'], ['taxrates.id']),
     )
 
-    id = sa.Column(sa.Integer(), primary_key=True, autoincrement=True, nullable=False)
-
-    upc = sa.Column(sa.String(length=13), nullable=True)
-
-    description = sa.Column(sa.String(length=30), nullable=True)
-
-    brand = sa.Column(sa.String(length=30), nullable=True)
-
-    formatted_name = sa.Column(sa.String(length=30), nullable=True)
-
-    normal_price = sa.Column(sa.Float(), nullable=True)
-
-    price_method = sa.Column('pricemethod', sa.SmallInteger(), nullable=True)
-
-    group_price = sa.Column('groupprice', sa.Float(), nullable=True)
-
-    quantity = sa.Column(sa.SmallInteger(), nullable=True)
-
-    special_price = sa.Column(sa.Float(), nullable=True)
-
-    special_price_method = sa.Column('specialpricemethod', sa.SmallInteger(), nullable=True)
-
-    special_group_price = sa.Column('specialgroupprice', sa.Float(), nullable=True)
-
-    special_quantity = sa.Column('specialquantity', sa.SmallInteger(), nullable=True)
-
-    start_date = sa.Column(sa.DateTime(), nullable=True)
-
-    end_date = sa.Column(sa.DateTime(), nullable=True)
-
-    department_number = sa.Column('department', sa.SmallInteger(), nullable=True)
     department = orm.relationship(
         Department,
-        primaryjoin=Department.number == department_number,
-        foreign_keys=[department_number],
+        primaryjoin='Department.number == Product.department_number',
+        foreign_keys='Product.department_number',
         doc="""
         Reference to the :class:`Department` to which the product belongs.
         """)
 
-    size = sa.Column(sa.String(length=9), nullable=True)
-
-    tax_rate_id = sa.Column('tax', sa.SmallInteger(), nullable=True)
     tax_rate = orm.relationship(TaxRate)
 
-    foodstamp = sa.Column(sa.Boolean(), nullable=True)
-
-    scale = sa.Column(sa.Boolean(), nullable=True)
-
-    # TODO: yikes, did i just code this all wrong the first time?  pretty sure
-    # this needs to change to a decimal column...
-    scale_price = sa.Column('scaleprice', sa.Boolean(), nullable=True)
-    # scale_price = sa.Column('scaleprice', sa.Numeric(precision=10, scale=2), nullable=True)
-
-    mix_match_code = sa.Column('mixmatchcode', sa.String(length=13), nullable=True)
-
-    created = sa.Column(StringableDateTime(), nullable=True)
-
-    modified = sa.Column(sa.DateTime(), nullable=True)
-
     # advertised = sa.Column(sa.Boolean(), nullable=True)
 
-    tare_weight = sa.Column('tareweight', sa.Float(), nullable=True)
-
-    discount = sa.Column(sa.SmallInteger(), nullable=True)
-
-    discount_type = sa.Column('discounttype', sa.SmallInteger(), nullable=True)
-
-    line_item_discountable = sa.Column(sa.Boolean(), nullable=True)
-
-    unit_of_measure = sa.Column('unitofmeasure', sa.String(length=15), nullable=True)
-
-    wicable = sa.Column(sa.SmallInteger(), nullable=True)
-
-    quantity_enforced = sa.Column('qttyEnforced', sa.Boolean(), nullable=True)
-
-    id_enforced = sa.Column('idEnforced', sa.SmallInteger(), nullable=True)
-
-    cost = sa.Column(sa.Float(), nullable=True)
-
-    in_use = sa.Column('inUse', sa.Boolean(), nullable=True)
-
-    flags = sa.Column('numflag', sa.Integer(), nullable=True)
-
-    subdepartment_number = sa.Column('subdept', sa.SmallInteger(), nullable=True)
     subdepartment = orm.relationship(
         Subdepartment,
-        primaryjoin=Subdepartment.number == subdepartment_number,
-        foreign_keys=[subdepartment_number],
+        primaryjoin='Subdepartment.number == Product.subdepartment_number',
+        foreign_keys='Product.subdepartment_number',
         doc="""
         Reference to the :class:`Subdepartment` to which the product belongs.
         """)
 
-    deposit = sa.Column(sa.Float(), nullable=True)
-
-    local = sa.Column(sa.Integer(), nullable=True)
-
-    store_id = sa.Column(sa.SmallInteger(), nullable=True)
-
-    default_vendor_id = sa.Column(sa.Integer(), nullable=True)
     default_vendor = orm.relationship(
         Vendor,
-        primaryjoin=Vendor.id == default_vendor_id,
-        foreign_keys=[default_vendor_id],
+        primaryjoin='Vendor.id == Product.default_vendor_id',
+        foreign_keys='Product.default_vendor_id',
         doc="""
         Reference to the default :class:`Vendor` from which the product is obtained.
         """)
+
     # TODO: deprecate / remove this?
     vendor = orm.synonym('default_vendor')
 
-    current_origin_id = sa.Column(sa.Integer(), nullable=True)
-
-    # TODO: some older DB's might not have this?  guess we'll see
-    last_sold = sa.Column(sa.DateTime(), nullable=True)
-
     like_code = association_proxy(
         '_like_code', 'like_code',
         creator=lambda lc: ProductLikeCode(like_code=lc),
     )
 
+    vendor_items = orm.relationship(
+        'VendorItem',
+        back_populates='product',
+        primaryjoin='VendorItem.upc == Product.upc',
+        foreign_keys='VendorItem.upc',
+        order_by='VendorItem.vendor_item_id',
+        doc="""
+        List of :class:`VendorItem` records for this product.
+        """)
+
+    @property
+    def default_vendor_item(self):
+        """
+        Returns the "default" vendor item record.  This will
+        correspond to the :attr:`default_vendor` if possible.
+
+        :rtype: :class:`VendorItem` or ``None``
+        """
+        if self.default_vendor:
+            for item in self.vendor_items:
+                if item.vendor_id == self.default_vendor.id:
+                    return item
+
+        if self.vendor_items:
+            return self.vendor_items[0]
+
     @property
     def full_description(self):
         fields = ['brand', 'description', 'size']
@@ -812,17 +758,12 @@ class VendorItem(Base):
     upc = sa.Column(sa.String(length=13), nullable=False)
     product = orm.relationship(
         Product,
+        back_populates='vendor_items',
         primaryjoin=Product.upc == upc,
         foreign_keys=[upc],
         doc="""
         Reference to the :class:`Product` to which this record applies.
-        """,
-        backref=orm.backref(
-            'vendor_items',
-            order_by=vendor_item_id,
-            doc="""
-            List of :class:`VendorItem` records for this product.
-            """))
+        """)
 
     brand = sa.Column(sa.String(length=50), nullable=True)
 
@@ -977,35 +918,12 @@ class ProductPhysicalLocation(Base):
     location = sa.Column(sa.SmallInteger(), nullable=True, default=0)
 
 
-class Employee(Base):
+class Employee(common.EmployeeBase, Base):
     """
-    Represents an employee within the organization.
+    Data model for ``employees`` table.
     """
     __tablename__ = 'employees'
 
-    number = sa.Column('emp_no', sa.SmallInteger(), primary_key=True, autoincrement=False, nullable=False)
-
-    cashier_password = sa.Column('CashierPassword', sa.String(length=50), nullable=True)
-
-    admin_password = sa.Column('AdminPassword', sa.String(length=50), nullable=True)
-
-    first_name = sa.Column('FirstName', sa.String(length=255), nullable=True)
-
-    last_name = sa.Column('LastName', sa.String(length=255), nullable=True)
-
-    job_title = sa.Column('JobTitle', sa.String(length=255), nullable=True)
-
-    active = sa.Column('EmpActive', sa.Boolean(), nullable=True)
-
-    frontend_security = sa.Column('frontendsecurity', sa.SmallInteger(), nullable=True)
-
-    backend_security = sa.Column('backendsecurity', sa.SmallInteger(), nullable=True)
-
-    birth_date = sa.Column('birthdate', sa.DateTime(), nullable=True)
-
-    def __str__(self):
-        return ' '.join([self.first_name or '', self.last_name or '']).strip()
-
 
 class MemberType(Base):
     """
@@ -1025,9 +943,11 @@ class MemberType(Base):
 
     ssi = sa.Column(sa.Boolean(), nullable=True)
 
-    # TODO: this was apparently added "recently" - isn't present in all DBs
-    # (need to figure out how to conditionally include it in model?)
-    # sales_code = sa.Column('salesCode', sa.Integer(), nullable=True)
+    # nb. this must be added explicitly if DB is new enough
+    #ignore_sales = sa.Column('ignoreSales', sa.Boolean(), nullable=True, default=False)
+
+    # nb. this must be added explicitly if DB is new enough
+    #sales_code = sa.Column('salesCode', sa.Integer(), nullable=True)
 
     def __str__(self):
         return self.description or ""
@@ -1153,7 +1073,7 @@ class Customer(Base):
         return "{} {}".format(self.first_name or '', self.last_name or '').strip()
 
 
-class CustData(Base):
+class CustomerClassic(Base):
     """
     Represents a customer of the organization.
 
@@ -1219,7 +1139,7 @@ class CustData(Base):
 
     member_info = orm.relationship(
         'MemberInfo',
-        primaryjoin='MemberInfo.card_number == CustData.card_number',
+        primaryjoin='MemberInfo.card_number == CustomerClassic.card_number',
         foreign_keys=[card_number],
         uselist=False,
         back_populates='customers',
@@ -1231,6 +1151,10 @@ class CustData(Base):
         return "{} {}".format(self.first_name or '', self.last_name or '').strip()
 
 
+# TODO: deprecate / remove this
+CustData = CustomerClassic
+
+
 class MemberInfo(Base):
     """
     Contact info regarding a member of the organization.
@@ -1239,14 +1163,14 @@ class MemberInfo(Base):
 
     card_number = sa.Column('card_no', sa.Integer(), primary_key=True, autoincrement=False, nullable=False)
 
-    last_name = sa.Column(sa.String(length=30), nullable=True)
-
     first_name = sa.Column(sa.String(length=30), nullable=True)
 
-    other_last_name = sa.Column('othlast_name', sa.String(length=30), nullable=True)
+    last_name = sa.Column(sa.String(length=30), nullable=True)
 
     other_first_name = sa.Column('othfirst_name', sa.String(length=30), nullable=True)
 
+    other_last_name = sa.Column('othlast_name', sa.String(length=30), nullable=True)
+
     street = sa.Column(sa.String(length=255), nullable=True)
 
     city = sa.Column(sa.String(length=20), nullable=True)
@@ -1259,19 +1183,22 @@ class MemberInfo(Base):
 
     email = sa.Column('email_1', sa.String(length=50), nullable=True)
 
-    email2 = sa.Column('email_2', sa.String(length=50), nullable=True)
+    email2 = sa.Column('email_2', sa.String(length=50), nullable=True, doc="""
+    NB. this is labeled "Alt. Phone" in CORE Office member view, and
+    is named `altPhone` when dealing with CORE Office webservices API.
+    """)
 
     ads_ok = sa.Column('ads_OK', sa.Boolean(), nullable=True, default=True)
 
     customers = orm.relationship(
-        CustData,
-        primaryjoin=CustData.card_number == card_number,
-        order_by=CustData.person_number,
-        foreign_keys=[CustData.card_number],
+        CustomerClassic,
+        primaryjoin=CustomerClassic.card_number == card_number,
+        order_by=CustomerClassic.person_number,
+        foreign_keys=[CustomerClassic.card_number],
         back_populates='member_info',
-        remote_side=CustData.card_number,
+        remote_side=CustomerClassic.card_number,
         doc="""
-        List of :class:`CustData` instances which are associated with this member info.
+        List of :class:`CustomerClassic` instances which are associated with this member info.
         """)
 
     dates = orm.relationship(
@@ -1279,6 +1206,7 @@ class MemberInfo(Base):
         primaryjoin='MemberDate.card_number == MemberInfo.card_number',
         foreign_keys='MemberDate.card_number',
         cascade='all, delete-orphan',
+        uselist=False,
         doc="""
         List of date records for the member.
         """,
@@ -1381,7 +1309,7 @@ class MemberDate(Base):
 
 class MemberContact(Base):
     """
-    Contact preferences for members
+    Member contacts
     """
     __tablename__ = 'memContact'
 
@@ -1408,6 +1336,19 @@ class MemberContact(Base):
         return str(self.preference)
 
 
+class MemberContactPreference(Base):
+    """
+    Member contact preferences
+    """
+    __tablename__ = 'memContactPrefs'
+
+    id = sa.Column('pref_id', sa.Integer(), primary_key=True, autoincrement=False, nullable=False)
+    description = sa.Column('pref_description', sa.String(length=50), nullable=True)
+
+    def __str__(self):
+        return self.description or ""
+
+
 class MemberBarcode(Base):
     """
     Additional barcode for a member.
@@ -1443,6 +1384,26 @@ class MemberNote(Base):
         return self.note or ""
 
 
+class CustomerNotification(Base):
+    """
+    Represents a customer notification for display at the lane.
+
+    https://github.com/CORE-POS/IS4C/blob/master/fannie/classlib2.0/data/models/op/CustomerNotificationsModel.php
+    """
+    __tablename__ = 'CustomerNotifications'
+
+    id = sa.Column('customerNotificationID', sa.Integer(), primary_key=True, autoincrement=True, nullable=False)
+    card_number = sa.Column('cardNo', sa.Integer(), nullable=True)
+    customer_id = sa.Column('customerID', sa.Integer(), nullable=True)
+    source = sa.Column(sa.String(length=50), nullable=True)
+    type = sa.Column(sa.String(length=50), nullable=True)
+    message = sa.Column(sa.String(length=255), nullable=True)
+    modifier_module = sa.Column('modifierModule', sa.String(length=50), nullable=True)
+
+    def __str__(self):
+        return self.message or ''
+
+
 class ReasonCode(Base):
     """
     Reason codes for legacy account suspensions.
@@ -1533,13 +1494,54 @@ class HouseCoupon(Base):
         return self.description or ''
 
 
+class Tender(Base):
+    """
+    Represents a tender for payment at POS
+    """
+    __tablename__ = 'tenders'
+
+    tender_id = sa.Column('TenderID', sa.Integer(), primary_key=True, nullable=False)
+
+    tender_code = sa.Column('TenderCode', sa.String(length=2), nullable=True)
+    tender_name = sa.Column('TenderName', sa.String(length=25), nullable=True)
+    tender_type = sa.Column('TenderType', sa.String(length=2), nullable=True)
+    change_message = sa.Column('ChangeMessage', sa.String(length=25), nullable=True)
+    min_amount = sa.Column('MinAmount', sa.Numeric(precision=10, scale=2), nullable=True)
+    max_amount = sa.Column('MaxAmount', sa.Numeric(precision=10, scale=2), nullable=True)
+    max_refund = sa.Column('MaxRefund', sa.Numeric(precision=10, scale=2), nullable=True)
+    tender_module = sa.Column('TenderModule', sa.String(length=50), nullable=True)
+    sales_code = sa.Column('SalesCode', sa.Integer(), nullable=True)
+
+    def __str__(self):
+        return self.tender_name or ''
+
+
+class CustomReceiptLine(Base):
+    """
+    Represents a "text string" line for a custom receipt.
+    """
+    __tablename__ = 'customReceipt'
+
+    # nb. this should be autoincrement, but we can't do that
+    # automatically via sqlalchemy when PK is composite
+    sequence = sa.Column('seq', sa.Integer(), primary_key=True, nullable=False)
+
+    type = sa.Column(sa.String(length=20), primary_key=True, nullable=False)
+    text = sa.Column(sa.String(length=80), nullable=True)
+
+    def __str__(self):
+        return self.text or ""
+
+
 class BatchType(Base):
     """
     Represents the definition of a batch type.
     """
     __tablename__ = 'batchType'
 
-    id = sa.Column('batchTypeID', sa.Integer(), primary_key=True, autoincrement=False, nullable=False)
+    # nb. this is *not* autoincrement for some reason; must
+    # calculate new ID manually based on max existing
+    id = sa.Column('batchTypeID', sa.Integer(), nullable=False, primary_key=True, autoincrement=False)
 
     description = sa.Column('typeDesc', sa.String(length=50), nullable=True)
 
@@ -1549,7 +1551,7 @@ class BatchType(Base):
 
     special_order_eligible = sa.Column('specialOrderEligible', sa.Boolean(), nullable=True, default=True)
 
-    editor_ui = sa.Column('editorUI', sa.Boolean(), nullable=True, default=True)
+    editor_ui = sa.Column('editorUI', sa.SmallInteger(), nullable=True, default=True)
 
     allow_single_store = sa.Column('allowSingleStore', sa.Boolean(), nullable=True, default=False)
 
@@ -1564,9 +1566,6 @@ class Batch(Base):
     Represents a batch.
     """
     __tablename__ = 'batches'
-    __table_args__ = (
-        sa.ForeignKeyConstraint(['batchType'], ['batchType.batchTypeID']),
-    )
 
     id = sa.Column('batchID', sa.Integer(), primary_key=True, autoincrement=True, nullable=False)
 
@@ -1576,7 +1575,8 @@ class Batch(Base):
 
     name = sa.Column('batchName', sa.String(length=80), nullable=True)
 
-    batch_type_id = sa.Column('batchType', sa.Integer(), nullable=True)
+    batch_type_id = sa.Column('batchType', sa.Integer(),
+                              sa.ForeignKey('batchType.batchTypeID'), nullable=True)
     batch_type = orm.relationship(BatchType)
 
     discount_type = sa.Column('discountType', sa.Integer(), nullable=True)
@@ -1598,16 +1598,18 @@ class BatchItem(Base):
     Represents a batch "list" item.
     """
     __tablename__ = 'batchList'
-    __table_args__ = (
-        sa.ForeignKeyConstraint(['batchID'], ['batches.batchID']),
-    )
 
     id = sa.Column('listID', sa.Integer(), primary_key=True, autoincrement=True, nullable=False)
 
-    batch_id = sa.Column('batchID', sa.Integer(), nullable=True)
+    batch_id = sa.Column('batchID', sa.Integer(),
+                         sa.ForeignKey('batches.batchID'), nullable=True)
     batch = orm.relationship(Batch, backref=orm.backref('items'))
 
     upc = sa.Column(sa.String(length=13), nullable=True)
+    product = orm.relationship(
+        Product,
+        primaryjoin=Product.upc == upc,
+        foreign_keys=[upc])
 
     sale_price = sa.Column('salePrice', sa.Numeric(precision=9, scale=3), nullable=True)
 
@@ -1743,3 +1745,22 @@ class PurchaseOrderNote(Base):
 
     def __str__(self):
         return self.notes or ""
+
+
+# the rest of this is a workaround to deal with the fact that some
+# CORE databases have columns which others do not.  i had assumed that
+# all would be more or less the same but not so in practice.  so if
+# your DB *does* have these columns, you must invoke the function
+# below in order to merge them into your schema.  you should do this
+# on app startup and they'll be available normally from then on.
+
+RUNTIME = {'added_latest_columns': False}
+
+def use_latest_columns():
+    if RUNTIME['added_latest_columns']:
+        return
+
+    MemberType.ignore_sales = sa.Column('ignoreSales', sa.Boolean(), nullable=True, default=False)
+    MemberType.sales_code = sa.Column('salesCode', sa.Integer(), nullable=True)
+
+    RUNTIME['added_latest_columns'] = True
diff --git a/corepos/db/office_trans/model.py b/corepos/db/office_trans/model.py
index 20c244c..c2b0959 100644
--- a/corepos/db/office_trans/model.py
+++ b/corepos/db/office_trans/model.py
@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  pyCOREPOS -- Python Interface to CORE POS
-#  Copyright © 2018-2023 Lance Edgar
+#  Copyright © 2018-2025 Lance Edgar
 #
 #  This file is part of pyCOREPOS.
 #
@@ -27,101 +27,65 @@ CORE POS Transaction Data Model
 import sqlalchemy as sa
 from sqlalchemy import orm
 
+from corepos.db.common import trans as common
+
 
 Base = orm.declarative_base()
 
 
-class TransactionDetailBase(object):
+# TODO: not sure what primary key should be for this?  am trying a
+# composite one so far, we'll see...cf. also andy's comments in
+# https://github.com/CORE-POS/IS4C/pull/1189#issuecomment-1597481138
+class StockPurchase(Base):
     """
-    Represents a POS transaction detail record.
+    Represents a member equity payment.
     """
+    __tablename__ = 'stockpurchases'
 
-    # store
-    store_row_id = sa.Column(sa.Integer(), primary_key=True, nullable=False)
-    store_id = sa.Column(sa.Integer(), nullable=True, default=0)
+    card_number = sa.Column('card_no', sa.Integer(), nullable=False, primary_key=True, autoincrement=False)
 
-    # register
-    register_number = sa.Column('register_no', sa.Integer(), nullable=True)
-    pos_row_id = sa.Column(sa.Integer(), nullable=True)
+    amount = sa.Column('stockPurchase', sa.Numeric(precision=10, scale=2), nullable=True)
+
+    datetime = sa.Column('tdate', sa.DateTime(), nullable=True, primary_key=True, autoincrement=False)
+
+    transaction_number = sa.Column('trans_num', sa.String(length=50), nullable=True, primary_key=True)
 
-    # txn
     transaction_id = sa.Column('trans_id', sa.Integer(), nullable=True)
-    transaction_number = sa.Column('trans_no', sa.Integer(), nullable=True)
-    transaction_type = sa.Column('trans_type', sa.String(length=1), nullable=True)
-    transaction_subtype = sa.Column('trans_subtype', sa.String(length=2), nullable=True)
-    transaction_status = sa.Column('trans_status', sa.String(length=1), nullable=True)
 
-    # timestamps
-    date_time = sa.Column('datetime', sa.DateTime(), nullable=True)
-
-    # cashier
-    employee_number = sa.Column('emp_no', sa.Integer(), nullable=True)
-
-    # customer
-    card_number = sa.Column('card_no', sa.Integer(), nullable=True)
-    member_type = sa.Column('memType', sa.Integer(), nullable=True)
-    staff = sa.Column(sa.Boolean(), nullable=True)
-
-    ##############################
-    # remainder is "line item" ...
-    ##############################
-
-    upc = sa.Column(sa.String(length=13), nullable=True)
-
-    department_number = sa.Column('department', sa.Integer(), nullable=True)
-
-    description = sa.Column(sa.String(length=30), nullable=True)
-
-    quantity = sa.Column(sa.Float(), nullable=True)
-
-    scale = sa.Column(sa.Boolean(), nullable=True, default=False)
-
-    cost = sa.Column(sa.Numeric(precision=10, scale=2), nullable=True)
-
-    unit_price = sa.Column('unitPrice', sa.Numeric(precision=10, scale=2), nullable=True)
-
-    total = sa.Column(sa.Numeric(precision=10, scale=2), nullable=True)
-
-    reg_price = sa.Column('regPrice', sa.Numeric(precision=10, scale=2), nullable=True)
-
-    tax = sa.Column(sa.Boolean(), nullable=True)
-
-    food_stamp = sa.Column('foodstamp', sa.Boolean(), nullable=True)
-
-    discount = sa.Column(sa.Numeric(precision=10, scale=2), nullable=True)
-
-    member_discount = sa.Column('memDiscount', sa.Numeric(precision=10, scale=2), nullable=True)
-
-    discountable = sa.Column(sa.Boolean(), nullable=True)
-
-    discount_type = sa.Column('discounttype', sa.Integer(), nullable=True)
-
-    voided = sa.Column(sa.Boolean(), nullable=True)
-
-    percent_discount = sa.Column('percentDiscount', sa.Integer(), nullable=True)
-
-    item_quantity = sa.Column('ItemQtty', sa.Float(), nullable=True)
-
-    volume_discount_type = sa.Column('volDiscType', sa.Integer(), nullable=True)
-
-    volume = sa.Column(sa.Integer(), nullable=True)
-
-    volume_special = sa.Column('VolSpecial', sa.Numeric(precision=10, scale=2), nullable=True)
-
-    mix_match = sa.Column('mixMatch', sa.String(length=13), nullable=True)
-
-    matched = sa.Column(sa.Boolean(), nullable=True)
-
-    num_flag = sa.Column('numflag', sa.Integer(), nullable=True, default=0)
-
-    char_flag = sa.Column('charflag', sa.String(length=2), nullable=True)
+    department_number = sa.Column('dept', sa.Integer(), nullable=True, primary_key=True, autoincrement=False)
 
     def __str__(self):
-        return self.description or ''
+        return f"#{self.card_number} for ${self.amount}"
 
 
-class TransactionDetail(TransactionDetailBase, Base):
+class EquityLiveBalance(Base):
+
+    __tablename__ = 'equity_live_balance'
+
+    member_number = sa.Column('memnum', sa.Integer(), nullable=False, primary_key=True, autoincrement=False)
+
+    payments = sa.Column(sa.Numeric(precision=10, scale=2), nullable=True)
+
+    start_date = sa.Column('startdate', sa.DateTime(), nullable=True)
+
+
+class DTransactionBase(common.TransactionDetailBase):
     """
-    Represents a POS transaction detail record.
+    Base class for ``dtransactions`` and similar models.
+    """
+    store_row_id = sa.Column(sa.Integer(), primary_key=True, nullable=False)
+
+    pos_row_id = sa.Column(sa.Integer(), nullable=True)
+    store_id = sa.Column(sa.Integer(), nullable=True, default=0)
+    date_time = sa.Column('datetime', sa.DateTime(), nullable=True)
+
+
+class DTransaction(DTransactionBase, Base):
+    """
+    Data model for ``dtransactions`` table.
     """
     __tablename__ = 'dtransactions'
+
+
+# TODO: deprecate / remove this
+TransactionDetail = DTransaction
diff --git a/corepos/db/office_trans_archive/__init__.py b/corepos/db/office_trans_archive/__init__.py
index e25b200..6ddb31d 100644
--- a/corepos/db/office_trans_archive/__init__.py
+++ b/corepos/db/office_trans_archive/__init__.py
@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  pyCOREPOS -- Python Interface to CORE POS
-#  Copyright © 2018-2022 Lance Edgar
+#  Copyright © 2018-2023 Lance Edgar
 #
 #  This file is part of pyCOREPOS.
 #
@@ -24,7 +24,9 @@
 "Archive" Transaction Database Interface
 """
 
-from sqlalchemy import orm
+import warnings
+warnings.warn("The `corepos.db.office_trans_archive` module is deprecated!  "
+              "Please use `corepos.db.office_arch` instead.",
+              DeprecationWarning, stacklevel=2)
 
-
-Session = orm.sessionmaker()
+from corepos.db.office_arch import *
diff --git a/corepos/db/office_trans_archive/model.py b/corepos/db/office_trans_archive/model.py
index 8f4a079..e57d071 100644
--- a/corepos/db/office_trans_archive/model.py
+++ b/corepos/db/office_trans_archive/model.py
@@ -24,16 +24,9 @@
 CORE POS Transaction Data Model
 """
 
-from sqlalchemy import orm
+import warnings
+warnings.warn("The `corepos.db.office_trans_archive.model` module is deprecated!  "
+              "Please use `corepos.db.office_arch.model` instead.",
+              DeprecationWarning, stacklevel=2)
 
-from corepos.db.office_trans.model import TransactionDetailBase
-
-
-Base = orm.declarative_base()
-
-
-class TransactionDetail(TransactionDetailBase, Base):
-    """
-    Represents a POS transaction detail record.
-    """
-    __tablename__ = 'bigArchive'
+from corepos.db.office_arch.model import *
diff --git a/corepos/enum.py b/corepos/enum.py
index 55619d8..93780c3 100644
--- a/corepos/enum.py
+++ b/corepos/enum.py
@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  pyCOREPOS -- Python Interface to CORE POS
-#  Copyright © 2018-2019 Lance Edgar
+#  Copyright © 2018-2024 Lance Edgar
 #
 #  This file is part of pyCOREPOS.
 #
@@ -24,22 +24,43 @@
 CORE POS enumeration constants
 """
 
-from __future__ import unicode_literals, absolute_import
-
-try:
-    from collections import OrderedDict
-except ImportError:
-    from ordereddict import OrderedDict
+from collections import OrderedDict
+from enum import Enum
 
 
+class CoreDbType(str, Enum):
+    office_op = 'office_op'
+    office_trans = 'office_trans'
+    office_arch = 'office_arch'
+
+
+BATCH_DISCOUNT_TYPE_TRACKING            = -1
 BATCH_DISCOUNT_TYPE_PRICE_CHANGE        = 0
 BATCH_DISCOUNT_TYPE_SALE_EVERYONE       = 1
 BATCH_DISCOUNT_TYPE_SALE_RESTRICTED     = 2
+BATCH_DISCOUNT_TYPE_SLIDING_PERCENT     = 3
+BATCH_DISCOUNT_TYPE_SLIDING_AMOUNT      = 5
 
 BATCH_DISCOUNT_TYPE = OrderedDict([
-    (BATCH_DISCOUNT_TYPE_PRICE_CHANGE,          "Price Change"),
+    (BATCH_DISCOUNT_TYPE_PRICE_CHANGE,          "None (Change regular price)"),
     (BATCH_DISCOUNT_TYPE_SALE_EVERYONE,         "Sale for everyone"),
-    (BATCH_DISCOUNT_TYPE_SALE_RESTRICTED,       "Member/Owner only sale"),
+    (BATCH_DISCOUNT_TYPE_SALE_RESTRICTED,       "Sale for Members"),
+    (BATCH_DISCOUNT_TYPE_SLIDING_PERCENT,       "Sliding % Off for Members"),
+    (BATCH_DISCOUNT_TYPE_SLIDING_AMOUNT,        "Sliding $ Off for Members"),
+    (BATCH_DISCOUNT_TYPE_TRACKING,              "Tracking (does not change any prices)"),
+])
+
+
+BATCH_EDITOR_UI_STANDARD                = 1
+BATCH_EDITOR_UI_PAIRED_SALE             = 2
+BATCH_EDITOR_UI_PARTIAL                 = 3
+BATCH_EDITOR_UI_TRACKING                = 4
+
+BATCH_EDITOR_UI = OrderedDict([
+    (BATCH_EDITOR_UI_STANDARD,                  "Standard"),
+    (BATCH_EDITOR_UI_PAIRED_SALE,               "Paired Sale"),
+    (BATCH_EDITOR_UI_PARTIAL,                   "Partial"),
+    (BATCH_EDITOR_UI_TRACKING,                  "Tracking"),
 ])
 
 
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..cf50f41
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,49 @@
+
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+
+[project]
+name = "pyCOREPOS"
+version = "0.5.1"
+description = "Python Interface to CORE POS"
+readme = "README.md"
+authors = [{name = "Lance Edgar", email = "lance@edbob.org"}]
+license = {text = "GNU GPL v3+"}
+classifiers = [
+        "Development Status :: 3 - Alpha",
+        "Environment :: Console",
+        "Environment :: Web Environment",
+        "Intended Audience :: Developers",
+        "License :: OSI Approved :: GNU General Public License v3 or later (GPLv3+)",
+        "Natural Language :: English",
+        "Operating System :: OS Independent",
+        "Programming Language :: Python",
+        "Programming Language :: Python :: 3",
+        "Topic :: Office/Business",
+        "Topic :: Software Development :: Libraries :: Python Modules",
+]
+
+dependencies = [
+        "mysql-connector-python",
+        "requests",
+        "SQLAlchemy>=1.4",
+]
+
+
+[project.urls]
+Homepage = "https://forgejo.wuttaproject.org/rattail/pycorepos"
+Repository = "https://forgejo.wuttaproject.org/rattail/pycorepos"
+Issues = "https://forgejo.wuttaproject.org/rattail/pycorepos/issues"
+Changelog = "https://forgejo.wuttaproject.org/rattail/pycorepos/src/branch/master/CHANGELOG.md"
+
+
+[tool.commitizen]
+version_provider = "pep621"
+tag_format = "v$version"
+update_changelog_on_bump = true
+
+
+[tool.hatch.build.targets.wheel]
+packages = ["corepos"]
diff --git a/setup.cfg b/setup.cfg
deleted file mode 100644
index 728f179..0000000
--- a/setup.cfg
+++ /dev/null
@@ -1,33 +0,0 @@
-# -*- coding: utf-8; -*-
-
-[metadata]
-name = pyCOREPOS
-version = attr: corepos.__version__
-author = Lance Edgar
-author_email = lance@edbob.org
-url = https://rattailproject.org/
-license = GNU GPL v3
-description = Python Interface to CORE POS
-long_description = file: README.rst
-classifiers =
-        Development Status :: 3 - Alpha
-        Environment :: Console
-        Environment :: Web Environment
-        Intended Audience :: Developers
-        License :: OSI Approved :: GNU General Public License v3 or later (GPLv3+)
-        Natural Language :: English
-        Operating System :: OS Independent
-        Programming Language :: Python
-        Programming Language :: Python :: 3
-        Topic :: Office/Business
-        Topic :: Software Development :: Libraries :: Python Modules
-
-
-[options]
-install_requires =
-        mysql-connector-python
-        requests
-        six
-        SQLAlchemy>=1.4
-
-packages = find:
diff --git a/tasks.py b/tasks.py
index a9b9fc3..6946a7f 100644
--- a/tasks.py
+++ b/tasks.py
@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  pyCOREPOS -- Python Interface to CORE POS
-#  Copyright © 2018-2020 Lance Edgar
+#  Copyright © 2018-2024 Lance Edgar
 #
 #  This file is part of pyCOREPOS.
 #
@@ -25,20 +25,32 @@ Tasks for 'pyCOREPOS' package
 """
 
 import os
+import re
 import shutil
 
 from invoke import task
 
 
 here = os.path.abspath(os.path.dirname(__file__))
-exec(open(os.path.join(here, 'corepos', '_version.py')).read())
+__version__ = None
+pattern = re.compile(r'^version = "(\d+\.\d+\.\d+)"$')
+with open(os.path.join(here, 'pyproject.toml'), 'rt') as f:
+    for line in f:
+        line = line.rstrip('\n')
+        match = pattern.match(line)
+        if match:
+            __version__ = match.group(1)
+            break
+if not __version__:
+    raise RuntimeError("could not parse version!")
 
 
 @task
-def release(ctx):
+def release(c):
     """
     Release a new version of 'pyCOREPOS'.
     """
-    shutil.rmtree('pyCOREPOS.egg-info')
-    ctx.run('python setup.py sdist --formats=gztar')
-    ctx.run('twine upload dist/pyCOREPOS-{}.tar.gz'.format(__version__))
+    if os.path.exists('pyCOREPOS.egg-info'):
+        shutil.rmtree('pyCOREPOS.egg-info')
+    c.run('python -m build --sdist')
+    c.run('twine upload dist/pycorepos-{}.tar.gz'.format(__version__))