diff --git a/hr_payroll_attendance/__init__.py b/hr_payroll_attendance/__init__.py
new file mode 100755
index 00000000..0650744f
--- /dev/null
+++ b/hr_payroll_attendance/__init__.py
@@ -0,0 +1 @@
+from . import models
diff --git a/hr_payroll_attendance/__manifest__.py b/hr_payroll_attendance/__manifest__.py
new file mode 100755
index 00000000..e8cf0a9b
--- /dev/null
+++ b/hr_payroll_attendance/__manifest__.py
@@ -0,0 +1,19 @@
+{
+    'name': 'Attendance on Payslips',
+    'description': 'Get Attendence numbers onto Employee Payslips.',
+    'version': '13.0.1.0.0',
+    'website': 'https://hibou.io/',
+    'author': 'Hibou Corp. <hello@hibou.io>',
+    'license': 'AGPL-3',
+    'category': 'Human Resources',
+    'data': [
+        'data/hr_payroll_attendance_data.xml',
+        'views/hr_contract_views.xml',
+        'views/hr_payslip_views.xml',
+    ],
+    'depends': [
+        'hr_payroll',
+        'hr_attendance',
+        'hr_payroll_overtime',
+    ],
+}
diff --git a/hr_payroll_attendance/data/hr_payroll_attendance_data.xml b/hr_payroll_attendance/data/hr_payroll_attendance_data.xml
new file mode 100644
index 00000000..6023dd08
--- /dev/null
+++ b/hr_payroll_attendance/data/hr_payroll_attendance_data.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<odoo>
+
+    <!-- Work Entry Type -->
+    <record id="work_input_attendance_overtime" model="hr.work.entry.type">
+        <field name="name">Attendance Overtime</field>
+        <field name="code">ATTN_OT</field>
+    </record>
+    <record id="work_input_attendance" model="hr.work.entry.type">
+        <field name="name">Attendance</field>
+        <field name="code">ATTN</field>
+        <field name="overtime_type_id" ref="hr_payroll_overtime.work_entry_overtime_type"/>
+        <field name="overtime_work_type_id" ref="work_input_attendance_overtime"/>
+    </record>
+
+    <!-- Rename Stock "Attendance" type -->
+    <record id="hr_work_entry.work_entry_type_attendance" model="hr.work.entry.type">
+        <field name="name">Work Calendar</field>
+    </record>
+
+</odoo>
diff --git a/hr_payroll_attendance/models/__init__.py b/hr_payroll_attendance/models/__init__.py
new file mode 100644
index 00000000..66b97981
--- /dev/null
+++ b/hr_payroll_attendance/models/__init__.py
@@ -0,0 +1,3 @@
+from . import hr_attendance
+from . import hr_contract
+from . import hr_payslip
diff --git a/hr_payroll_attendance/models/hr_attendance.py b/hr_payroll_attendance/models/hr_attendance.py
new file mode 100644
index 00000000..de4a0d3b
--- /dev/null
+++ b/hr_payroll_attendance/models/hr_attendance.py
@@ -0,0 +1,7 @@
+from odoo import fields, models
+
+
+class HrAttendance(models.Model):
+    _inherit = 'hr.attendance'
+
+    payslip_id = fields.Many2one('hr.payslip', string="Payslip", readonly=True)
diff --git a/hr_payroll_attendance/models/hr_contract.py b/hr_payroll_attendance/models/hr_contract.py
new file mode 100755
index 00000000..c6a70483
--- /dev/null
+++ b/hr_payroll_attendance/models/hr_contract.py
@@ -0,0 +1,7 @@
+from odoo import models, fields
+
+
+class HrContract(models.Model):
+    _inherit = 'hr.contract'
+
+    paid_hourly_attendance = fields.Boolean(string="Paid Hourly Attendance")
diff --git a/hr_payroll_attendance/models/hr_payslip.py b/hr_payroll_attendance/models/hr_payslip.py
new file mode 100755
index 00000000..b41f9648
--- /dev/null
+++ b/hr_payroll_attendance/models/hr_payslip.py
@@ -0,0 +1,89 @@
+from collections import defaultdict
+from odoo import api, fields, models, _
+
+
+class HrPayslip(models.Model):
+    _inherit = 'hr.payslip'
+
+    attendance_ids = fields.One2many('hr.attendance', 'payslip_id', string='Attendances',
+                                     help='Attendances represented by payslip.',
+                                     states={'draft': [('readonly', False)], 'verify': [('readonly', False)]})
+    attendance_count = fields.Integer(compute='_compute_attendance_count')
+
+    @api.depends('attendance_ids', 'attendance_ids.payslip_id')
+    def _compute_attendance_count(self):
+        for payslip in self:
+            payslip.attendance_count = len(payslip.attendance_ids)
+
+    @api.onchange('worked_days_line_ids')
+    def _onchange_worked_days_line_ids(self):
+        # super()._onchange_worked_days_line_ids()
+        attendance_type = self.env.ref('hr_payroll_attendance.work_input_attendance', raise_if_not_found=False)
+        if not self.worked_days_line_ids.filtered(lambda line: line.work_entry_type_id == attendance_type):
+            self.attendance_ids.write({'payslip_id': False})
+
+    @api.onchange('employee_id', 'struct_id', 'contract_id', 'date_from', 'date_to')
+    def _onchange_employee(self):
+        res = super()._onchange_employee()
+        if self.state == 'draft' and self.contract_id.paid_hourly_attendance:
+            self.attendance_ids = self.env['hr.attendance'].search([
+                ('employee_id', '=', self.employee_id.id),
+                ('check_out', '<=', self.date_to),
+                '|', ('payslip_id', '=', False),
+                     ('payslip_id', '=', self.id),
+            ])
+            self._onchange_attendance_ids()
+        return res
+
+    @api.onchange('attendance_ids')
+    def _onchange_attendance_ids(self):
+        original_work_type = self.env.ref('hr_work_entry.work_entry_type_attendance', raise_if_not_found=False)
+        attendance_type = self.env.ref('hr_payroll_attendance.work_input_attendance', raise_if_not_found=False)
+        if not attendance_type:
+            return
+
+        if original_work_type:
+            types_to_remove = original_work_type + attendance_type
+        else:
+            types_to_remove = attendance_type
+
+        work_data = self._pre_aggregate_attendance_data()
+        processed_data = self.aggregate_overtime(work_data)
+
+        # TODO is it appropriate to remove all lines? Ideally we would only remove the old type.
+        lines_to_keep = self.worked_days_line_ids.filtered(lambda x: x.work_entry_type_id not in types_to_remove)
+        work_lines_vals = [(5, 0, 0)] + [(4, line.id, False) for line in lines_to_keep]
+        # work_lines_vals = [(5, 0, 0)]
+        work_lines_vals += [(0, 0, {
+            'number_of_days': data[0],
+            'number_of_hours': data[1],
+            'amount': data[1] * data[2] * self._wage_for_work_type(work_type),
+            'contract_id': self.contract_id.id,
+            'work_entry_type_id': work_type.id,
+        }) for work_type, data in processed_data.items()]
+        self.update({'worked_days_line_ids': work_lines_vals})
+
+    def _wage_for_work_type(self, work_type):
+        # Override if you pay differently for different work types
+        return self.contract_id.wage
+
+    def _pre_aggregate_attendance_data(self):
+        attendance_type = self.env.ref('hr_payroll_attendance.work_input_attendance', raise_if_not_found=False)
+        worked_attn = defaultdict(list)
+        for attn in self.attendance_ids:
+            if attn.worked_hours:
+                # Avoid in/outs
+                attn_iso = attn.check_in.isocalendar()
+                worked_attn[attn_iso].append((attendance_type, attn.worked_hours, attn))
+        res = [(k, worked_attn[k]) for k in sorted(worked_attn.keys())]
+        return res
+
+    def action_open_attendances(self):
+        self.ensure_one()
+        return {
+            'type': 'ir.actions.act_window',
+            'name': _('Paid Attendances'),
+            'res_model': 'hr.attendance',
+            'view_mode': 'tree,form',
+            'domain': [('id', 'in', self.attendance_ids.ids)],
+        }
diff --git a/hr_payroll_attendance/tests/__init__.py b/hr_payroll_attendance/tests/__init__.py
new file mode 100644
index 00000000..8904658a
--- /dev/null
+++ b/hr_payroll_attendance/tests/__init__.py
@@ -0,0 +1 @@
+from . import test_payroll_attendance
diff --git a/hr_payroll_attendance/tests/test_payroll_attendance.py b/hr_payroll_attendance/tests/test_payroll_attendance.py
new file mode 100644
index 00000000..80472a52
--- /dev/null
+++ b/hr_payroll_attendance/tests/test_payroll_attendance.py
@@ -0,0 +1,122 @@
+from collections import defaultdict
+from odoo.tests import common
+
+
+class TestUsPayslip(common.TransactionCase):
+
+    def setUp(self):
+        super().setUp()
+        self.test_hourly_wage = 21.5
+        self.employee = self.env.ref('hr.employee_hne')
+        self.contract = self.env['hr.contract'].create({
+            'name': 'Test',
+            'employee_id': self.employee.id,
+            'structure_type_id': self.env.ref('hr_payroll.structure_type_employee').id,
+            'date_start': '2020-01-01',
+            'resource_calendar_id': self.employee.resource_calendar_id.id,
+            'wage': self.test_hourly_wage,
+            'paid_hourly_attendance': True,
+            'state': 'open',
+        })
+        self._setup_attendance(self.employee)
+        self.payslip = self.env['hr.payslip'].create({
+            'name': 'test slip',
+            'employee_id': self.employee.id,
+            'date_from': '2020-01-06',
+            'date_to': '2020-01-19',
+        })
+
+    def _setup_attendance(self, employee):
+        # Total 127.37 hours in 2 weeks.
+        # Six 9-hour days in one week (plus a little). 58.97 hours in that week.
+        attendances = self.env['hr.attendance']
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-06 10:00:00',  # Monday
+            'check_out': '2020-01-06 19:00:00',
+        })
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-07 10:00:00',
+            'check_out': '2020-01-07 19:00:00',
+        })
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-08 10:00:00',
+            'check_out': '2020-01-08 19:00:00',
+        })
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-09 10:00:00',
+            'check_out': '2020-01-09 19:00:00',
+        })
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-10 10:00:00',
+            'check_out': '2020-01-10 19:00:00',
+        })
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-11 06:00:00',
+            'check_out': '2020-01-11 19:58:12',
+        })
+
+        # Five 10-hour days, Two 9-hour days (plus a little) in one week. 68.4 hours in that week
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-13 08:00:00',  # Monday
+            'check_out': '2020-01-13 18:00:00',
+        })
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-14 08:00:00',
+            'check_out': '2020-01-14 18:00:00',
+        })
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-15 08:00:00',
+            'check_out': '2020-01-15 18:00:00',
+        })
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-16 08:00:00',
+            'check_out': '2020-01-16 18:00:00',
+        })
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-17 08:00:00',
+            'check_out': '2020-01-17 18:00:00',
+        })
+        attendances += self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-18 09:00:00',
+            'check_out': '2020-01-18 18:00:00',
+        })
+        last = self.env['hr.attendance'].create({
+            'employee_id': employee.id,
+            'check_in': '2020-01-19 09:00:00',
+            'check_out': '2020-01-19 18:24:00',
+        })
+        attendances += last
+        return last
+
+    def _getCategories(self):
+        categories = defaultdict(float)
+        for line in self.payslip.line_ids:
+            category_id = line.category_id
+            category_code = line.category_id.code
+            while category_code:
+                categories[category_code] += line.total
+                category_id = category_id.parent_id
+                category_code = category_id.code
+        return categories
+
+    def test_attendance_hourly(self):
+        self.payslip._onchange_employee()
+        self.assertTrue(self.payslip.contract_id, 'No auto-discovered contract!')
+        self.payslip.compute_sheet()
+        # 58.97 => 40hr regular, 18.97hr OT
+        # 68.4  => 40hr regular, 28.4hr  OT
+        # (80 * 21.50) + (47.37 * 21.50 * 1.5) = 3247.6825
+        cats = self._getCategories()
+        self.assertAlmostEqual(cats['BASIC'], 3247.68, 2)
diff --git a/hr_payroll_attendance/views/hr_contract_views.xml b/hr_payroll_attendance/views/hr_contract_views.xml
new file mode 100755
index 00000000..6ef64386
--- /dev/null
+++ b/hr_payroll_attendance/views/hr_contract_views.xml
@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<odoo>
+
+    <record id="hr_contract_form_inherit" model="ir.ui.view">
+        <field name="name">hr.contract.form.inherit</field>
+        <field name="model">hr.contract</field>
+        <field name="priority">20</field>
+        <field name="inherit_id" ref="hr_contract.hr_contract_view_form"/>
+        <field name="arch" type="xml">
+        <data>
+            <xpath expr="//field[@name='advantages']" position="after">
+                <field name="paid_hourly_attendance"/>
+            </xpath>
+            <xpath expr="//div[@name='wage']/span" position="replace">
+                <span attrs="{'invisible': [('paid_hourly_attendance', '=', True)]}">/ pay period</span>
+                <span attrs="{'invisible': [('paid_hourly_attendance', '=', False)]}">/ hour</span>
+            </xpath>
+        </data>
+        </field>
+    </record>
+
+</odoo>
diff --git a/hr_payroll_attendance/views/hr_payslip_views.xml b/hr_payroll_attendance/views/hr_payslip_views.xml
new file mode 100644
index 00000000..292f413f
--- /dev/null
+++ b/hr_payroll_attendance/views/hr_payslip_views.xml
@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<odoo>
+
+    <record id="hr_payslip_view_form_inherit" model="ir.ui.view">
+        <field name="name">hr.payslip.view.form.inherit</field>
+        <field name="model">hr.payslip</field>
+        <field name="inherit_id" ref="hr_payroll.view_hr_payslip_form"/>
+        <field name="arch" type="xml">
+            <xpath expr="//div[@name='button_box']" position="inside">
+                <button class="oe_stat_button" name="action_open_attendances" type="object" icon="fa-calendar" attrs="{'invisible': [('attendance_count', '=', 0)]}">
+                    <field string="Attendances" name="attendance_count" widget="statinfo"/>
+                </button>
+            </xpath>
+            <xpath expr="//field[@name='number']" position="after">
+                <field name="attendance_ids" invisible="1"/>
+            </xpath>
+        </field>
+    </record>
+    
+</odoo>