feat(payments): add the payments schema, currency domain and money type

Stand up the payments data foundation: a self-contained `payments` Postgres
schema for the in-game currency, wallets, benefits, catalog, orders and the
append-only operations ledger, behind a domain package — nothing wired to real
money yet.

- Migration 00010: the `payments` schema and a NOLOGIN confinement role (ALL on
  payments.*, nothing on backend); the ledger with a BEFORE UPDATE/DELETE
  append-only trigger and a partial idempotency index; the materialised
  balances/benefits; the catalog (atoms seeded) + products + per-method prices;
  the typed single-row config; orders and payment_events. There is no
  cross-schema foreign key — account_id is a plain uuid kept consistent in code,
  which keeps the domain extractable. Expand-contract and reversible.
- Money is a bigint in the currency's minor units carried by a `Money` value
  type (exact, math/big): no float ever touches an amount, and a whole-unit
  currency cannot hold a fraction.
- Extend jetgen to generate the payments schema; construct the service in the
  composition root behind a narrow interface with a boot reachability check.
- Tests: integration (role confinement via SET ROLE, the append-only trigger,
  CHECK constraints, the idempotency index, and a forward+backward migration),
  Money unit tests, and an import-boundary test keeping the payments jet code
  private to the domain.
- Docs: PLAN.md, docs/PAYMENTS.md (+ _ru mirror) updated to the built model.

backend/internal/postgres/jet/payments/model/balances.go

@@ -0,0 +1,20 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package model
+
+import (
+	"github.com/google/uuid"
+	"time"
+)
+
+type Balances struct {
+	AccountID uuid.UUID `sql:"primary_key"`
+	Source    string    `sql:"primary_key"`
+	Chips     int32
+	UpdatedAt time.Time
+}

backend/internal/postgres/jet/payments/model/benefits.go

@@ -0,0 +1,22 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package model
+
+import (
+	"github.com/google/uuid"
+	"time"
+)
+
+type Benefits struct {
+	AccountID    uuid.UUID `sql:"primary_key"`
+	Origin       string    `sql:"primary_key"`
+	AdsPaidUntil *time.Time
+	AdsForever   bool
+	Hints        int32
+	UpdatedAt    time.Time
+}

backend/internal/postgres/jet/payments/model/catalog_atom.go

@@ -0,0 +1,12 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package model
+
+type CatalogAtom struct {
+	AtomType string `sql:"primary_key"`
+}

backend/internal/postgres/jet/payments/model/config.go

@@ -0,0 +1,17 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package model
+
+type Config struct {
+	OnlyRow               bool `sql:"primary_key"`
+	RewardedPayoutChips   int32
+	CooldownGlobalSeconds int32
+	CooldownVsAiSeconds   int32
+	CooldownHintSeconds   int32
+	OrderTTLSeconds       int32
+}

backend/internal/postgres/jet/payments/model/ledger.go

@@ -0,0 +1,28 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package model
+
+import (
+	"github.com/google/uuid"
+	"time"
+)
+
+type Ledger struct {
+	LedgerID          uuid.UUID `sql:"primary_key"`
+	AccountID         uuid.UUID
+	Kind              string
+	Source            *string
+	Origin            *string
+	ChipsDelta        int32
+	ProductID         *uuid.UUID
+	OrderID           *uuid.UUID
+	Provider          *string
+	ProviderPaymentID *string
+	Snapshot          *string
+	CreatedAt         time.Time
+}

backend/internal/postgres/jet/payments/model/orders.go

@@ -0,0 +1,28 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package model
+
+import (
+	"github.com/google/uuid"
+	"time"
+)
+
+type Orders struct {
+	OrderID           uuid.UUID `sql:"primary_key"`
+	AccountID         uuid.UUID
+	Platform          string
+	ProductID         uuid.UUID
+	ExpectedAmount    int64
+	Currency          string
+	Origin            string
+	Status            string
+	Provider          *string
+	ProviderPaymentID *string
+	CreatedAt         time.Time
+	UpdatedAt         time.Time
+}

backend/internal/postgres/jet/payments/model/payment_events.go

@@ -0,0 +1,23 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package model
+
+import (
+	"github.com/google/uuid"
+	"time"
+)
+
+type PaymentEvents struct {
+	EventID      uuid.UUID `sql:"primary_key"`
+	AccountID    uuid.UUID
+	OrderID      *uuid.UUID
+	Type         string
+	Payload      *string
+	CreatedAt    time.Time
+	DispatchedAt *time.Time
+}

backend/internal/postgres/jet/payments/model/product.go

@@ -0,0 +1,21 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package model
+
+import (
+	"github.com/google/uuid"
+	"time"
+)
+
+type Product struct {
+	ProductID uuid.UUID `sql:"primary_key"`
+	Title     string
+	Active    bool
+	CreatedAt time.Time
+	UpdatedAt time.Time
+}

backend/internal/postgres/jet/payments/model/product_item.go

@@ -0,0 +1,18 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package model
+
+import (
+	"github.com/google/uuid"
+)
+
+type ProductItem struct {
+	ProductID uuid.UUID `sql:"primary_key"`
+	AtomType  string    `sql:"primary_key"`
+	Quantity  int32
+}

backend/internal/postgres/jet/payments/model/product_price.go

@@ -0,0 +1,19 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package model
+
+import (
+	"github.com/google/uuid"
+)
+
+type ProductPrice struct {
+	ProductID uuid.UUID
+	Method    *string
+	Currency  string
+	Amount    int64
+}

backend/internal/postgres/jet/payments/table/balances.go

@@ -0,0 +1,87 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+import (
+	"github.com/go-jet/jet/v2/postgres"
+)
+
+var Balances = newBalancesTable("payments", "balances", "")
+
+type balancesTable struct {
+	postgres.Table
+
+	// Columns
+	AccountID postgres.ColumnString
+	Source    postgres.ColumnString
+	Chips     postgres.ColumnInteger
+	UpdatedAt postgres.ColumnTimestampz
+
+	AllColumns     postgres.ColumnList
+	MutableColumns postgres.ColumnList
+	DefaultColumns postgres.ColumnList
+}
+
+type BalancesTable struct {
+	balancesTable
+
+	EXCLUDED balancesTable
+}
+
+// AS creates new BalancesTable with assigned alias
+func (a BalancesTable) AS(alias string) *BalancesTable {
+	return newBalancesTable(a.SchemaName(), a.TableName(), alias)
+}
+
+// Schema creates new BalancesTable with assigned schema name
+func (a BalancesTable) FromSchema(schemaName string) *BalancesTable {
+	return newBalancesTable(schemaName, a.TableName(), a.Alias())
+}
+
+// WithPrefix creates new BalancesTable with assigned table prefix
+func (a BalancesTable) WithPrefix(prefix string) *BalancesTable {
+	return newBalancesTable(a.SchemaName(), prefix+a.TableName(), a.TableName())
+}
+
+// WithSuffix creates new BalancesTable with assigned table suffix
+func (a BalancesTable) WithSuffix(suffix string) *BalancesTable {
+	return newBalancesTable(a.SchemaName(), a.TableName()+suffix, a.TableName())
+}
+
+func newBalancesTable(schemaName, tableName, alias string) *BalancesTable {
+	return &BalancesTable{
+		balancesTable: newBalancesTableImpl(schemaName, tableName, alias),
+		EXCLUDED:      newBalancesTableImpl("", "excluded", ""),
+	}
+}
+
+func newBalancesTableImpl(schemaName, tableName, alias string) balancesTable {
+	var (
+		AccountIDColumn = postgres.StringColumn("account_id")
+		SourceColumn    = postgres.StringColumn("source")
+		ChipsColumn     = postgres.IntegerColumn("chips")
+		UpdatedAtColumn = postgres.TimestampzColumn("updated_at")
+		allColumns      = postgres.ColumnList{AccountIDColumn, SourceColumn, ChipsColumn, UpdatedAtColumn}
+		mutableColumns  = postgres.ColumnList{ChipsColumn, UpdatedAtColumn}
+		defaultColumns  = postgres.ColumnList{ChipsColumn, UpdatedAtColumn}
+	)
+
+	return balancesTable{
+		Table: postgres.NewTable(schemaName, tableName, alias, allColumns...),
+
+		//Columns
+		AccountID: AccountIDColumn,
+		Source:    SourceColumn,
+		Chips:     ChipsColumn,
+		UpdatedAt: UpdatedAtColumn,
+
+		AllColumns:     allColumns,
+		MutableColumns: mutableColumns,
+		DefaultColumns: defaultColumns,
+	}
+}

backend/internal/postgres/jet/payments/table/benefits.go

@@ -0,0 +1,93 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+import (
+	"github.com/go-jet/jet/v2/postgres"
+)
+
+var Benefits = newBenefitsTable("payments", "benefits", "")
+
+type benefitsTable struct {
+	postgres.Table
+
+	// Columns
+	AccountID    postgres.ColumnString
+	Origin       postgres.ColumnString
+	AdsPaidUntil postgres.ColumnTimestampz
+	AdsForever   postgres.ColumnBool
+	Hints        postgres.ColumnInteger
+	UpdatedAt    postgres.ColumnTimestampz
+
+	AllColumns     postgres.ColumnList
+	MutableColumns postgres.ColumnList
+	DefaultColumns postgres.ColumnList
+}
+
+type BenefitsTable struct {
+	benefitsTable
+
+	EXCLUDED benefitsTable
+}
+
+// AS creates new BenefitsTable with assigned alias
+func (a BenefitsTable) AS(alias string) *BenefitsTable {
+	return newBenefitsTable(a.SchemaName(), a.TableName(), alias)
+}
+
+// Schema creates new BenefitsTable with assigned schema name
+func (a BenefitsTable) FromSchema(schemaName string) *BenefitsTable {
+	return newBenefitsTable(schemaName, a.TableName(), a.Alias())
+}
+
+// WithPrefix creates new BenefitsTable with assigned table prefix
+func (a BenefitsTable) WithPrefix(prefix string) *BenefitsTable {
+	return newBenefitsTable(a.SchemaName(), prefix+a.TableName(), a.TableName())
+}
+
+// WithSuffix creates new BenefitsTable with assigned table suffix
+func (a BenefitsTable) WithSuffix(suffix string) *BenefitsTable {
+	return newBenefitsTable(a.SchemaName(), a.TableName()+suffix, a.TableName())
+}
+
+func newBenefitsTable(schemaName, tableName, alias string) *BenefitsTable {
+	return &BenefitsTable{
+		benefitsTable: newBenefitsTableImpl(schemaName, tableName, alias),
+		EXCLUDED:      newBenefitsTableImpl("", "excluded", ""),
+	}
+}
+
+func newBenefitsTableImpl(schemaName, tableName, alias string) benefitsTable {
+	var (
+		AccountIDColumn    = postgres.StringColumn("account_id")
+		OriginColumn       = postgres.StringColumn("origin")
+		AdsPaidUntilColumn = postgres.TimestampzColumn("ads_paid_until")
+		AdsForeverColumn   = postgres.BoolColumn("ads_forever")
+		HintsColumn        = postgres.IntegerColumn("hints")
+		UpdatedAtColumn    = postgres.TimestampzColumn("updated_at")
+		allColumns         = postgres.ColumnList{AccountIDColumn, OriginColumn, AdsPaidUntilColumn, AdsForeverColumn, HintsColumn, UpdatedAtColumn}
+		mutableColumns     = postgres.ColumnList{AdsPaidUntilColumn, AdsForeverColumn, HintsColumn, UpdatedAtColumn}
+		defaultColumns     = postgres.ColumnList{AdsForeverColumn, HintsColumn, UpdatedAtColumn}
+	)
+
+	return benefitsTable{
+		Table: postgres.NewTable(schemaName, tableName, alias, allColumns...),
+
+		//Columns
+		AccountID:    AccountIDColumn,
+		Origin:       OriginColumn,
+		AdsPaidUntil: AdsPaidUntilColumn,
+		AdsForever:   AdsForeverColumn,
+		Hints:        HintsColumn,
+		UpdatedAt:    UpdatedAtColumn,
+
+		AllColumns:     allColumns,
+		MutableColumns: mutableColumns,
+		DefaultColumns: defaultColumns,
+	}
+}

backend/internal/postgres/jet/payments/table/catalog_atom.go

@@ -0,0 +1,78 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+import (
+	"github.com/go-jet/jet/v2/postgres"
+)
+
+var CatalogAtom = newCatalogAtomTable("payments", "catalog_atom", "")
+
+type catalogAtomTable struct {
+	postgres.Table
+
+	// Columns
+	AtomType postgres.ColumnString
+
+	AllColumns     postgres.ColumnList
+	MutableColumns postgres.ColumnList
+	DefaultColumns postgres.ColumnList
+}
+
+type CatalogAtomTable struct {
+	catalogAtomTable
+
+	EXCLUDED catalogAtomTable
+}
+
+// AS creates new CatalogAtomTable with assigned alias
+func (a CatalogAtomTable) AS(alias string) *CatalogAtomTable {
+	return newCatalogAtomTable(a.SchemaName(), a.TableName(), alias)
+}
+
+// Schema creates new CatalogAtomTable with assigned schema name
+func (a CatalogAtomTable) FromSchema(schemaName string) *CatalogAtomTable {
+	return newCatalogAtomTable(schemaName, a.TableName(), a.Alias())
+}
+
+// WithPrefix creates new CatalogAtomTable with assigned table prefix
+func (a CatalogAtomTable) WithPrefix(prefix string) *CatalogAtomTable {
+	return newCatalogAtomTable(a.SchemaName(), prefix+a.TableName(), a.TableName())
+}
+
+// WithSuffix creates new CatalogAtomTable with assigned table suffix
+func (a CatalogAtomTable) WithSuffix(suffix string) *CatalogAtomTable {
+	return newCatalogAtomTable(a.SchemaName(), a.TableName()+suffix, a.TableName())
+}
+
+func newCatalogAtomTable(schemaName, tableName, alias string) *CatalogAtomTable {
+	return &CatalogAtomTable{
+		catalogAtomTable: newCatalogAtomTableImpl(schemaName, tableName, alias),
+		EXCLUDED:         newCatalogAtomTableImpl("", "excluded", ""),
+	}
+}
+
+func newCatalogAtomTableImpl(schemaName, tableName, alias string) catalogAtomTable {
+	var (
+		AtomTypeColumn = postgres.StringColumn("atom_type")
+		allColumns     = postgres.ColumnList{AtomTypeColumn}
+		mutableColumns = postgres.ColumnList{}
+		defaultColumns = postgres.ColumnList{}
+	)
+
+	return catalogAtomTable{
+		Table: postgres.NewTable(schemaName, tableName, alias, allColumns...),
+
+		//Columns
+		AtomType: AtomTypeColumn,
+
+		AllColumns:     allColumns,
+		MutableColumns: mutableColumns,
+		DefaultColumns: defaultColumns,
+	}
+}

backend/internal/postgres/jet/payments/table/config.go

@@ -0,0 +1,93 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+import (
+	"github.com/go-jet/jet/v2/postgres"
+)
+
+var Config = newConfigTable("payments", "config", "")
+
+type configTable struct {
+	postgres.Table
+
+	// Columns
+	OnlyRow               postgres.ColumnBool
+	RewardedPayoutChips   postgres.ColumnInteger
+	CooldownGlobalSeconds postgres.ColumnInteger
+	CooldownVsAiSeconds   postgres.ColumnInteger
+	CooldownHintSeconds   postgres.ColumnInteger
+	OrderTTLSeconds       postgres.ColumnInteger
+
+	AllColumns     postgres.ColumnList
+	MutableColumns postgres.ColumnList
+	DefaultColumns postgres.ColumnList
+}
+
+type ConfigTable struct {
+	configTable
+
+	EXCLUDED configTable
+}
+
+// AS creates new ConfigTable with assigned alias
+func (a ConfigTable) AS(alias string) *ConfigTable {
+	return newConfigTable(a.SchemaName(), a.TableName(), alias)
+}
+
+// Schema creates new ConfigTable with assigned schema name
+func (a ConfigTable) FromSchema(schemaName string) *ConfigTable {
+	return newConfigTable(schemaName, a.TableName(), a.Alias())
+}
+
+// WithPrefix creates new ConfigTable with assigned table prefix
+func (a ConfigTable) WithPrefix(prefix string) *ConfigTable {
+	return newConfigTable(a.SchemaName(), prefix+a.TableName(), a.TableName())
+}
+
+// WithSuffix creates new ConfigTable with assigned table suffix
+func (a ConfigTable) WithSuffix(suffix string) *ConfigTable {
+	return newConfigTable(a.SchemaName(), a.TableName()+suffix, a.TableName())
+}
+
+func newConfigTable(schemaName, tableName, alias string) *ConfigTable {
+	return &ConfigTable{
+		configTable: newConfigTableImpl(schemaName, tableName, alias),
+		EXCLUDED:    newConfigTableImpl("", "excluded", ""),
+	}
+}
+
+func newConfigTableImpl(schemaName, tableName, alias string) configTable {
+	var (
+		OnlyRowColumn               = postgres.BoolColumn("only_row")
+		RewardedPayoutChipsColumn   = postgres.IntegerColumn("rewarded_payout_chips")
+		CooldownGlobalSecondsColumn = postgres.IntegerColumn("cooldown_global_seconds")
+		CooldownVsAiSecondsColumn   = postgres.IntegerColumn("cooldown_vs_ai_seconds")
+		CooldownHintSecondsColumn   = postgres.IntegerColumn("cooldown_hint_seconds")
+		OrderTTLSecondsColumn       = postgres.IntegerColumn("order_ttl_seconds")
+		allColumns                  = postgres.ColumnList{OnlyRowColumn, RewardedPayoutChipsColumn, CooldownGlobalSecondsColumn, CooldownVsAiSecondsColumn, CooldownHintSecondsColumn, OrderTTLSecondsColumn}
+		mutableColumns              = postgres.ColumnList{RewardedPayoutChipsColumn, CooldownGlobalSecondsColumn, CooldownVsAiSecondsColumn, CooldownHintSecondsColumn, OrderTTLSecondsColumn}
+		defaultColumns              = postgres.ColumnList{OnlyRowColumn, RewardedPayoutChipsColumn, CooldownGlobalSecondsColumn, CooldownVsAiSecondsColumn, CooldownHintSecondsColumn, OrderTTLSecondsColumn}
+	)
+
+	return configTable{
+		Table: postgres.NewTable(schemaName, tableName, alias, allColumns...),
+
+		//Columns
+		OnlyRow:               OnlyRowColumn,
+		RewardedPayoutChips:   RewardedPayoutChipsColumn,
+		CooldownGlobalSeconds: CooldownGlobalSecondsColumn,
+		CooldownVsAiSeconds:   CooldownVsAiSecondsColumn,
+		CooldownHintSeconds:   CooldownHintSecondsColumn,
+		OrderTTLSeconds:       OrderTTLSecondsColumn,
+
+		AllColumns:     allColumns,
+		MutableColumns: mutableColumns,
+		DefaultColumns: defaultColumns,
+	}
+}

backend/internal/postgres/jet/payments/table/ledger.go

@@ -0,0 +1,111 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+import (
+	"github.com/go-jet/jet/v2/postgres"
+)
+
+var Ledger = newLedgerTable("payments", "ledger", "")
+
+type ledgerTable struct {
+	postgres.Table
+
+	// Columns
+	LedgerID          postgres.ColumnString
+	AccountID         postgres.ColumnString
+	Kind              postgres.ColumnString
+	Source            postgres.ColumnString
+	Origin            postgres.ColumnString
+	ChipsDelta        postgres.ColumnInteger
+	ProductID         postgres.ColumnString
+	OrderID           postgres.ColumnString
+	Provider          postgres.ColumnString
+	ProviderPaymentID postgres.ColumnString
+	Snapshot          postgres.ColumnString
+	CreatedAt         postgres.ColumnTimestampz
+
+	AllColumns     postgres.ColumnList
+	MutableColumns postgres.ColumnList
+	DefaultColumns postgres.ColumnList
+}
+
+type LedgerTable struct {
+	ledgerTable
+
+	EXCLUDED ledgerTable
+}
+
+// AS creates new LedgerTable with assigned alias
+func (a LedgerTable) AS(alias string) *LedgerTable {
+	return newLedgerTable(a.SchemaName(), a.TableName(), alias)
+}
+
+// Schema creates new LedgerTable with assigned schema name
+func (a LedgerTable) FromSchema(schemaName string) *LedgerTable {
+	return newLedgerTable(schemaName, a.TableName(), a.Alias())
+}
+
+// WithPrefix creates new LedgerTable with assigned table prefix
+func (a LedgerTable) WithPrefix(prefix string) *LedgerTable {
+	return newLedgerTable(a.SchemaName(), prefix+a.TableName(), a.TableName())
+}
+
+// WithSuffix creates new LedgerTable with assigned table suffix
+func (a LedgerTable) WithSuffix(suffix string) *LedgerTable {
+	return newLedgerTable(a.SchemaName(), a.TableName()+suffix, a.TableName())
+}
+
+func newLedgerTable(schemaName, tableName, alias string) *LedgerTable {
+	return &LedgerTable{
+		ledgerTable: newLedgerTableImpl(schemaName, tableName, alias),
+		EXCLUDED:    newLedgerTableImpl("", "excluded", ""),
+	}
+}
+
+func newLedgerTableImpl(schemaName, tableName, alias string) ledgerTable {
+	var (
+		LedgerIDColumn          = postgres.StringColumn("ledger_id")
+		AccountIDColumn         = postgres.StringColumn("account_id")
+		KindColumn              = postgres.StringColumn("kind")
+		SourceColumn            = postgres.StringColumn("source")
+		OriginColumn            = postgres.StringColumn("origin")
+		ChipsDeltaColumn        = postgres.IntegerColumn("chips_delta")
+		ProductIDColumn         = postgres.StringColumn("product_id")
+		OrderIDColumn           = postgres.StringColumn("order_id")
+		ProviderColumn          = postgres.StringColumn("provider")
+		ProviderPaymentIDColumn = postgres.StringColumn("provider_payment_id")
+		SnapshotColumn          = postgres.StringColumn("snapshot")
+		CreatedAtColumn         = postgres.TimestampzColumn("created_at")
+		allColumns              = postgres.ColumnList{LedgerIDColumn, AccountIDColumn, KindColumn, SourceColumn, OriginColumn, ChipsDeltaColumn, ProductIDColumn, OrderIDColumn, ProviderColumn, ProviderPaymentIDColumn, SnapshotColumn, CreatedAtColumn}
+		mutableColumns          = postgres.ColumnList{AccountIDColumn, KindColumn, SourceColumn, OriginColumn, ChipsDeltaColumn, ProductIDColumn, OrderIDColumn, ProviderColumn, ProviderPaymentIDColumn, SnapshotColumn, CreatedAtColumn}
+		defaultColumns          = postgres.ColumnList{ChipsDeltaColumn, CreatedAtColumn}
+	)
+
+	return ledgerTable{
+		Table: postgres.NewTable(schemaName, tableName, alias, allColumns...),
+
+		//Columns
+		LedgerID:          LedgerIDColumn,
+		AccountID:         AccountIDColumn,
+		Kind:              KindColumn,
+		Source:            SourceColumn,
+		Origin:            OriginColumn,
+		ChipsDelta:        ChipsDeltaColumn,
+		ProductID:         ProductIDColumn,
+		OrderID:           OrderIDColumn,
+		Provider:          ProviderColumn,
+		ProviderPaymentID: ProviderPaymentIDColumn,
+		Snapshot:          SnapshotColumn,
+		CreatedAt:         CreatedAtColumn,
+
+		AllColumns:     allColumns,
+		MutableColumns: mutableColumns,
+		DefaultColumns: defaultColumns,
+	}
+}

backend/internal/postgres/jet/payments/table/orders.go

@@ -0,0 +1,111 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+import (
+	"github.com/go-jet/jet/v2/postgres"
+)
+
+var Orders = newOrdersTable("payments", "orders", "")
+
+type ordersTable struct {
+	postgres.Table
+
+	// Columns
+	OrderID           postgres.ColumnString
+	AccountID         postgres.ColumnString
+	Platform          postgres.ColumnString
+	ProductID         postgres.ColumnString
+	ExpectedAmount    postgres.ColumnInteger
+	Currency          postgres.ColumnString
+	Origin            postgres.ColumnString
+	Status            postgres.ColumnString
+	Provider          postgres.ColumnString
+	ProviderPaymentID postgres.ColumnString
+	CreatedAt         postgres.ColumnTimestampz
+	UpdatedAt         postgres.ColumnTimestampz
+
+	AllColumns     postgres.ColumnList
+	MutableColumns postgres.ColumnList
+	DefaultColumns postgres.ColumnList
+}
+
+type OrdersTable struct {
+	ordersTable
+
+	EXCLUDED ordersTable
+}
+
+// AS creates new OrdersTable with assigned alias
+func (a OrdersTable) AS(alias string) *OrdersTable {
+	return newOrdersTable(a.SchemaName(), a.TableName(), alias)
+}
+
+// Schema creates new OrdersTable with assigned schema name
+func (a OrdersTable) FromSchema(schemaName string) *OrdersTable {
+	return newOrdersTable(schemaName, a.TableName(), a.Alias())
+}
+
+// WithPrefix creates new OrdersTable with assigned table prefix
+func (a OrdersTable) WithPrefix(prefix string) *OrdersTable {
+	return newOrdersTable(a.SchemaName(), prefix+a.TableName(), a.TableName())
+}
+
+// WithSuffix creates new OrdersTable with assigned table suffix
+func (a OrdersTable) WithSuffix(suffix string) *OrdersTable {
+	return newOrdersTable(a.SchemaName(), a.TableName()+suffix, a.TableName())
+}
+
+func newOrdersTable(schemaName, tableName, alias string) *OrdersTable {
+	return &OrdersTable{
+		ordersTable: newOrdersTableImpl(schemaName, tableName, alias),
+		EXCLUDED:    newOrdersTableImpl("", "excluded", ""),
+	}
+}
+
+func newOrdersTableImpl(schemaName, tableName, alias string) ordersTable {
+	var (
+		OrderIDColumn           = postgres.StringColumn("order_id")
+		AccountIDColumn         = postgres.StringColumn("account_id")
+		PlatformColumn          = postgres.StringColumn("platform")
+		ProductIDColumn         = postgres.StringColumn("product_id")
+		ExpectedAmountColumn    = postgres.IntegerColumn("expected_amount")
+		CurrencyColumn          = postgres.StringColumn("currency")
+		OriginColumn            = postgres.StringColumn("origin")
+		StatusColumn            = postgres.StringColumn("status")
+		ProviderColumn          = postgres.StringColumn("provider")
+		ProviderPaymentIDColumn = postgres.StringColumn("provider_payment_id")
+		CreatedAtColumn         = postgres.TimestampzColumn("created_at")
+		UpdatedAtColumn         = postgres.TimestampzColumn("updated_at")
+		allColumns              = postgres.ColumnList{OrderIDColumn, AccountIDColumn, PlatformColumn, ProductIDColumn, ExpectedAmountColumn, CurrencyColumn, OriginColumn, StatusColumn, ProviderColumn, ProviderPaymentIDColumn, CreatedAtColumn, UpdatedAtColumn}
+		mutableColumns          = postgres.ColumnList{AccountIDColumn, PlatformColumn, ProductIDColumn, ExpectedAmountColumn, CurrencyColumn, OriginColumn, StatusColumn, ProviderColumn, ProviderPaymentIDColumn, CreatedAtColumn, UpdatedAtColumn}
+		defaultColumns          = postgres.ColumnList{StatusColumn, CreatedAtColumn, UpdatedAtColumn}
+	)
+
+	return ordersTable{
+		Table: postgres.NewTable(schemaName, tableName, alias, allColumns...),
+
+		//Columns
+		OrderID:           OrderIDColumn,
+		AccountID:         AccountIDColumn,
+		Platform:          PlatformColumn,
+		ProductID:         ProductIDColumn,
+		ExpectedAmount:    ExpectedAmountColumn,
+		Currency:          CurrencyColumn,
+		Origin:            OriginColumn,
+		Status:            StatusColumn,
+		Provider:          ProviderColumn,
+		ProviderPaymentID: ProviderPaymentIDColumn,
+		CreatedAt:         CreatedAtColumn,
+		UpdatedAt:         UpdatedAtColumn,
+
+		AllColumns:     allColumns,
+		MutableColumns: mutableColumns,
+		DefaultColumns: defaultColumns,
+	}
+}

backend/internal/postgres/jet/payments/table/payment_events.go

@@ -0,0 +1,96 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+import (
+	"github.com/go-jet/jet/v2/postgres"
+)
+
+var PaymentEvents = newPaymentEventsTable("payments", "payment_events", "")
+
+type paymentEventsTable struct {
+	postgres.Table
+
+	// Columns
+	EventID      postgres.ColumnString
+	AccountID    postgres.ColumnString
+	OrderID      postgres.ColumnString
+	Type         postgres.ColumnString
+	Payload      postgres.ColumnString
+	CreatedAt    postgres.ColumnTimestampz
+	DispatchedAt postgres.ColumnTimestampz
+
+	AllColumns     postgres.ColumnList
+	MutableColumns postgres.ColumnList
+	DefaultColumns postgres.ColumnList
+}
+
+type PaymentEventsTable struct {
+	paymentEventsTable
+
+	EXCLUDED paymentEventsTable
+}
+
+// AS creates new PaymentEventsTable with assigned alias
+func (a PaymentEventsTable) AS(alias string) *PaymentEventsTable {
+	return newPaymentEventsTable(a.SchemaName(), a.TableName(), alias)
+}
+
+// Schema creates new PaymentEventsTable with assigned schema name
+func (a PaymentEventsTable) FromSchema(schemaName string) *PaymentEventsTable {
+	return newPaymentEventsTable(schemaName, a.TableName(), a.Alias())
+}
+
+// WithPrefix creates new PaymentEventsTable with assigned table prefix
+func (a PaymentEventsTable) WithPrefix(prefix string) *PaymentEventsTable {
+	return newPaymentEventsTable(a.SchemaName(), prefix+a.TableName(), a.TableName())
+}
+
+// WithSuffix creates new PaymentEventsTable with assigned table suffix
+func (a PaymentEventsTable) WithSuffix(suffix string) *PaymentEventsTable {
+	return newPaymentEventsTable(a.SchemaName(), a.TableName()+suffix, a.TableName())
+}
+
+func newPaymentEventsTable(schemaName, tableName, alias string) *PaymentEventsTable {
+	return &PaymentEventsTable{
+		paymentEventsTable: newPaymentEventsTableImpl(schemaName, tableName, alias),
+		EXCLUDED:           newPaymentEventsTableImpl("", "excluded", ""),
+	}
+}
+
+func newPaymentEventsTableImpl(schemaName, tableName, alias string) paymentEventsTable {
+	var (
+		EventIDColumn      = postgres.StringColumn("event_id")
+		AccountIDColumn    = postgres.StringColumn("account_id")
+		OrderIDColumn      = postgres.StringColumn("order_id")
+		TypeColumn         = postgres.StringColumn("type")
+		PayloadColumn      = postgres.StringColumn("payload")
+		CreatedAtColumn    = postgres.TimestampzColumn("created_at")
+		DispatchedAtColumn = postgres.TimestampzColumn("dispatched_at")
+		allColumns         = postgres.ColumnList{EventIDColumn, AccountIDColumn, OrderIDColumn, TypeColumn, PayloadColumn, CreatedAtColumn, DispatchedAtColumn}
+		mutableColumns     = postgres.ColumnList{AccountIDColumn, OrderIDColumn, TypeColumn, PayloadColumn, CreatedAtColumn, DispatchedAtColumn}
+		defaultColumns     = postgres.ColumnList{CreatedAtColumn}
+	)
+
+	return paymentEventsTable{
+		Table: postgres.NewTable(schemaName, tableName, alias, allColumns...),
+
+		//Columns
+		EventID:      EventIDColumn,
+		AccountID:    AccountIDColumn,
+		OrderID:      OrderIDColumn,
+		Type:         TypeColumn,
+		Payload:      PayloadColumn,
+		CreatedAt:    CreatedAtColumn,
+		DispatchedAt: DispatchedAtColumn,
+
+		AllColumns:     allColumns,
+		MutableColumns: mutableColumns,
+		DefaultColumns: defaultColumns,
+	}
+}

backend/internal/postgres/jet/payments/table/product.go

@@ -0,0 +1,90 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+import (
+	"github.com/go-jet/jet/v2/postgres"
+)
+
+var Product = newProductTable("payments", "product", "")
+
+type productTable struct {
+	postgres.Table
+
+	// Columns
+	ProductID postgres.ColumnString
+	Title     postgres.ColumnString
+	Active    postgres.ColumnBool
+	CreatedAt postgres.ColumnTimestampz
+	UpdatedAt postgres.ColumnTimestampz
+
+	AllColumns     postgres.ColumnList
+	MutableColumns postgres.ColumnList
+	DefaultColumns postgres.ColumnList
+}
+
+type ProductTable struct {
+	productTable
+
+	EXCLUDED productTable
+}
+
+// AS creates new ProductTable with assigned alias
+func (a ProductTable) AS(alias string) *ProductTable {
+	return newProductTable(a.SchemaName(), a.TableName(), alias)
+}
+
+// Schema creates new ProductTable with assigned schema name
+func (a ProductTable) FromSchema(schemaName string) *ProductTable {
+	return newProductTable(schemaName, a.TableName(), a.Alias())
+}
+
+// WithPrefix creates new ProductTable with assigned table prefix
+func (a ProductTable) WithPrefix(prefix string) *ProductTable {
+	return newProductTable(a.SchemaName(), prefix+a.TableName(), a.TableName())
+}
+
+// WithSuffix creates new ProductTable with assigned table suffix
+func (a ProductTable) WithSuffix(suffix string) *ProductTable {
+	return newProductTable(a.SchemaName(), a.TableName()+suffix, a.TableName())
+}
+
+func newProductTable(schemaName, tableName, alias string) *ProductTable {
+	return &ProductTable{
+		productTable: newProductTableImpl(schemaName, tableName, alias),
+		EXCLUDED:     newProductTableImpl("", "excluded", ""),
+	}
+}
+
+func newProductTableImpl(schemaName, tableName, alias string) productTable {
+	var (
+		ProductIDColumn = postgres.StringColumn("product_id")
+		TitleColumn     = postgres.StringColumn("title")
+		ActiveColumn    = postgres.BoolColumn("active")
+		CreatedAtColumn = postgres.TimestampzColumn("created_at")
+		UpdatedAtColumn = postgres.TimestampzColumn("updated_at")
+		allColumns      = postgres.ColumnList{ProductIDColumn, TitleColumn, ActiveColumn, CreatedAtColumn, UpdatedAtColumn}
+		mutableColumns  = postgres.ColumnList{TitleColumn, ActiveColumn, CreatedAtColumn, UpdatedAtColumn}
+		defaultColumns  = postgres.ColumnList{TitleColumn, ActiveColumn, CreatedAtColumn, UpdatedAtColumn}
+	)
+
+	return productTable{
+		Table: postgres.NewTable(schemaName, tableName, alias, allColumns...),
+
+		//Columns
+		ProductID: ProductIDColumn,
+		Title:     TitleColumn,
+		Active:    ActiveColumn,
+		CreatedAt: CreatedAtColumn,
+		UpdatedAt: UpdatedAtColumn,
+
+		AllColumns:     allColumns,
+		MutableColumns: mutableColumns,
+		DefaultColumns: defaultColumns,
+	}
+}

backend/internal/postgres/jet/payments/table/product_item.go

@@ -0,0 +1,84 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+import (
+	"github.com/go-jet/jet/v2/postgres"
+)
+
+var ProductItem = newProductItemTable("payments", "product_item", "")
+
+type productItemTable struct {
+	postgres.Table
+
+	// Columns
+	ProductID postgres.ColumnString
+	AtomType  postgres.ColumnString
+	Quantity  postgres.ColumnInteger
+
+	AllColumns     postgres.ColumnList
+	MutableColumns postgres.ColumnList
+	DefaultColumns postgres.ColumnList
+}
+
+type ProductItemTable struct {
+	productItemTable
+
+	EXCLUDED productItemTable
+}
+
+// AS creates new ProductItemTable with assigned alias
+func (a ProductItemTable) AS(alias string) *ProductItemTable {
+	return newProductItemTable(a.SchemaName(), a.TableName(), alias)
+}
+
+// Schema creates new ProductItemTable with assigned schema name
+func (a ProductItemTable) FromSchema(schemaName string) *ProductItemTable {
+	return newProductItemTable(schemaName, a.TableName(), a.Alias())
+}
+
+// WithPrefix creates new ProductItemTable with assigned table prefix
+func (a ProductItemTable) WithPrefix(prefix string) *ProductItemTable {
+	return newProductItemTable(a.SchemaName(), prefix+a.TableName(), a.TableName())
+}
+
+// WithSuffix creates new ProductItemTable with assigned table suffix
+func (a ProductItemTable) WithSuffix(suffix string) *ProductItemTable {
+	return newProductItemTable(a.SchemaName(), a.TableName()+suffix, a.TableName())
+}
+
+func newProductItemTable(schemaName, tableName, alias string) *ProductItemTable {
+	return &ProductItemTable{
+		productItemTable: newProductItemTableImpl(schemaName, tableName, alias),
+		EXCLUDED:         newProductItemTableImpl("", "excluded", ""),
+	}
+}
+
+func newProductItemTableImpl(schemaName, tableName, alias string) productItemTable {
+	var (
+		ProductIDColumn = postgres.StringColumn("product_id")
+		AtomTypeColumn  = postgres.StringColumn("atom_type")
+		QuantityColumn  = postgres.IntegerColumn("quantity")
+		allColumns      = postgres.ColumnList{ProductIDColumn, AtomTypeColumn, QuantityColumn}
+		mutableColumns  = postgres.ColumnList{QuantityColumn}
+		defaultColumns  = postgres.ColumnList{}
+	)
+
+	return productItemTable{
+		Table: postgres.NewTable(schemaName, tableName, alias, allColumns...),
+
+		//Columns
+		ProductID: ProductIDColumn,
+		AtomType:  AtomTypeColumn,
+		Quantity:  QuantityColumn,
+
+		AllColumns:     allColumns,
+		MutableColumns: mutableColumns,
+		DefaultColumns: defaultColumns,
+	}
+}

backend/internal/postgres/jet/payments/table/product_price.go

@@ -0,0 +1,87 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+import (
+	"github.com/go-jet/jet/v2/postgres"
+)
+
+var ProductPrice = newProductPriceTable("payments", "product_price", "")
+
+type productPriceTable struct {
+	postgres.Table
+
+	// Columns
+	ProductID postgres.ColumnString
+	Method    postgres.ColumnString
+	Currency  postgres.ColumnString
+	Amount    postgres.ColumnInteger
+
+	AllColumns     postgres.ColumnList
+	MutableColumns postgres.ColumnList
+	DefaultColumns postgres.ColumnList
+}
+
+type ProductPriceTable struct {
+	productPriceTable
+
+	EXCLUDED productPriceTable
+}
+
+// AS creates new ProductPriceTable with assigned alias
+func (a ProductPriceTable) AS(alias string) *ProductPriceTable {
+	return newProductPriceTable(a.SchemaName(), a.TableName(), alias)
+}
+
+// Schema creates new ProductPriceTable with assigned schema name
+func (a ProductPriceTable) FromSchema(schemaName string) *ProductPriceTable {
+	return newProductPriceTable(schemaName, a.TableName(), a.Alias())
+}
+
+// WithPrefix creates new ProductPriceTable with assigned table prefix
+func (a ProductPriceTable) WithPrefix(prefix string) *ProductPriceTable {
+	return newProductPriceTable(a.SchemaName(), prefix+a.TableName(), a.TableName())
+}
+
+// WithSuffix creates new ProductPriceTable with assigned table suffix
+func (a ProductPriceTable) WithSuffix(suffix string) *ProductPriceTable {
+	return newProductPriceTable(a.SchemaName(), a.TableName()+suffix, a.TableName())
+}
+
+func newProductPriceTable(schemaName, tableName, alias string) *ProductPriceTable {
+	return &ProductPriceTable{
+		productPriceTable: newProductPriceTableImpl(schemaName, tableName, alias),
+		EXCLUDED:          newProductPriceTableImpl("", "excluded", ""),
+	}
+}
+
+func newProductPriceTableImpl(schemaName, tableName, alias string) productPriceTable {
+	var (
+		ProductIDColumn = postgres.StringColumn("product_id")
+		MethodColumn    = postgres.StringColumn("method")
+		CurrencyColumn  = postgres.StringColumn("currency")
+		AmountColumn    = postgres.IntegerColumn("amount")
+		allColumns      = postgres.ColumnList{ProductIDColumn, MethodColumn, CurrencyColumn, AmountColumn}
+		mutableColumns  = postgres.ColumnList{ProductIDColumn, MethodColumn, CurrencyColumn, AmountColumn}
+		defaultColumns  = postgres.ColumnList{}
+	)
+
+	return productPriceTable{
+		Table: postgres.NewTable(schemaName, tableName, alias, allColumns...),
+
+		//Columns
+		ProductID: ProductIDColumn,
+		Method:    MethodColumn,
+		Currency:  CurrencyColumn,
+		Amount:    AmountColumn,
+
+		AllColumns:     allColumns,
+		MutableColumns: mutableColumns,
+		DefaultColumns: defaultColumns,
+	}
+}

backend/internal/postgres/jet/payments/table/table_use_schema.go

@@ -0,0 +1,23 @@
+//
+// Code generated by go-jet DO NOT EDIT.
+//
+// WARNING: Changes to this file may cause incorrect behavior
+// and will be lost if the code is regenerated
+//
+
+package table
+
+// UseSchema sets a new schema name for all generated table SQL builder types. It is recommended to invoke
+// this method only once at the beginning of the program.
+func UseSchema(schema string) {
+	Balances = Balances.FromSchema(schema)
+	Benefits = Benefits.FromSchema(schema)
+	CatalogAtom = CatalogAtom.FromSchema(schema)
+	Config = Config.FromSchema(schema)
+	Ledger = Ledger.FromSchema(schema)
+	Orders = Orders.FromSchema(schema)
+	PaymentEvents = PaymentEvents.FromSchema(schema)
+	Product = Product.FromSchema(schema)
+	ProductItem = ProductItem.FromSchema(schema)
+	ProductPrice = ProductPrice.FromSchema(schema)
+}

backend/internal/postgres/migrations/00010_payments_foundation.sql

@@ -0,0 +1,266 @@
+-- Payments data foundation: a self-contained `payments` schema for the in-game
+-- currency, wallets, benefits, catalog, orders and the append-only operations
+-- ledger. Nothing is wired to real money yet — this is the substrate the rest of
+-- the payments domain builds on. Mechanics live in docs/PAYMENTS.md.
+--
+-- Isolation. The schema is confined to a dedicated NOLOGIN role that holds ALL
+-- privileges on `payments.*` and none on `backend.*`; the backend application
+-- keeps its single (superuser) pool, so the DB grants are a stepping-stone to a
+-- future separate login/process rather than a runtime wall. The runtime wall is
+-- code-level: only the payments package reaches these tables (an import-boundary
+-- test guards it). There is deliberately NO cross-schema foreign key to
+-- `backend.accounts`: `account_id` is a plain uuid, kept referentially honest in
+-- code and joined to the tombstoned account / retained-identities dossier by the
+-- stable account id — which keeps the domain extractable into its own database.
+--
+-- The ledger is append-only, enforced by a trigger (a superuser bypasses table
+-- privileges, so a REVOKE would not bind the application). Money is stored as an
+-- integer amount in the currency's minor units (RUB kopecks; Votes/Stars/chips
+-- are whole units, scale 1), never a float — integer-currency integrality is
+-- therefore structural.
+--
+-- Legacy note: backend.accounts.hint_balance and backend.accounts.paid_account
+-- are superseded by the segmented model here and are DEPRECATED. They are NOT
+-- dropped in this expand phase — reads still use them until the currency core
+-- flips them, and the DROP is a later contract-phase migration (image rollback
+-- must stay DB-safe). Neither was ever set in production.
+--
+-- Expand-contract: everything here is additive in its own schema, so a backend
+-- image rollback stays DB-safe (older code simply ignores the new schema).
+
+-- +goose Up
+
+CREATE SCHEMA IF NOT EXISTS payments;
+
+-- +goose StatementBegin
+DO $$
+BEGIN
+    IF NOT EXISTS (SELECT FROM pg_roles WHERE rolname = 'payments') THEN
+        CREATE ROLE payments NOLOGIN;
+    END IF;
+END
+$$;
+-- +goose StatementEnd
+
+GRANT USAGE ON SCHEMA payments TO payments;
+
+-- Base value types (atoms) a product is composed of. A fixed, code-known set.
+CREATE TABLE payments.catalog_atom (
+    atom_type text NOT NULL,
+    CONSTRAINT catalog_atom_pkey PRIMARY KEY (atom_type),
+    CONSTRAINT catalog_atom_type_chk
+        CHECK ((atom_type = ANY (ARRAY['chips'::text, 'hints'::text, 'noads_days'::text, 'tournament'::text])))
+);
+
+INSERT INTO payments.catalog_atom (atom_type) VALUES
+    ('chips'), ('hints'), ('noads_days'), ('tournament');
+
+-- A sellable product: a set of atoms at a price. Soft-deleted (deactivated),
+-- never removed, so historical orders/ledger keep resolving it.
+CREATE TABLE payments.product (
+    product_id uuid NOT NULL,
+    title text DEFAULT ''::text NOT NULL,
+    active boolean DEFAULT true NOT NULL,
+    created_at timestamp with time zone DEFAULT now() NOT NULL,
+    updated_at timestamp with time zone DEFAULT now() NOT NULL,
+    CONSTRAINT product_pkey PRIMARY KEY (product_id)
+);
+
+-- The atom composition of a product (e.g. 250 hints + 30 no-ads days).
+CREATE TABLE payments.product_item (
+    product_id uuid NOT NULL,
+    atom_type text NOT NULL,
+    quantity integer NOT NULL,
+    CONSTRAINT product_item_pkey PRIMARY KEY (product_id, atom_type),
+    CONSTRAINT product_item_product_fkey FOREIGN KEY (product_id)
+        REFERENCES payments.product (product_id) ON DELETE CASCADE,
+    CONSTRAINT product_item_atom_fkey FOREIGN KEY (atom_type)
+        REFERENCES payments.catalog_atom (atom_type),
+    CONSTRAINT product_item_quantity_chk CHECK ((quantity > 0))
+);
+
+-- Price of a product. A chip pack carries a money price per method
+-- (multi-currency Votes/Stars/RUB); a value carries a single chips price
+-- (currency='CHIP', method NULL). `amount` is an integer in the currency's
+-- minor units (RUB kopecks; Votes/Stars/chips whole, scale 1).
+CREATE TABLE payments.product_price (
+    product_id uuid NOT NULL,
+    method text,
+    currency text NOT NULL,
+    amount bigint NOT NULL,
+    CONSTRAINT product_price_product_fkey FOREIGN KEY (product_id)
+        REFERENCES payments.product (product_id) ON DELETE CASCADE,
+    CONSTRAINT product_price_method_chk
+        CHECK ((method IS NULL) OR (method = ANY (ARRAY['vk'::text, 'telegram'::text, 'direct'::text]))),
+    CONSTRAINT product_price_currency_chk
+        CHECK ((currency = ANY (ARRAY['RUB'::text, 'VOTE'::text, 'XTR'::text, 'CHIP'::text]))),
+    CONSTRAINT product_price_amount_chk CHECK ((amount >= 0))
+);
+
+-- One price row per (product, method, currency); NULL method (a value's chip
+-- price) collapses to one row via the COALESCE key.
+CREATE UNIQUE INDEX product_price_unique_idx
+    ON payments.product_price (product_id, COALESCE(method, ''::text), currency);
+
+-- A pre-created purchase intent. `expected_amount` is in `currency` minor units.
+CREATE TABLE payments.orders (
+    order_id uuid NOT NULL,
+    account_id uuid NOT NULL,
+    platform text NOT NULL,
+    product_id uuid NOT NULL,
+    expected_amount bigint NOT NULL,
+    currency text NOT NULL,
+    origin text NOT NULL,
+    status text DEFAULT 'pending'::text NOT NULL,
+    provider text,
+    provider_payment_id text,
+    created_at timestamp with time zone DEFAULT now() NOT NULL,
+    updated_at timestamp with time zone DEFAULT now() NOT NULL,
+    CONSTRAINT orders_pkey PRIMARY KEY (order_id),
+    CONSTRAINT orders_product_fkey FOREIGN KEY (product_id)
+        REFERENCES payments.product (product_id),
+    CONSTRAINT orders_status_chk
+        CHECK ((status = ANY (ARRAY['pending'::text, 'paid'::text, 'expired'::text]))),
+    CONSTRAINT orders_origin_chk
+        CHECK ((origin = ANY (ARRAY['vk'::text, 'telegram'::text, 'direct'::text]))),
+    CONSTRAINT orders_currency_chk
+        CHECK ((currency = ANY (ARRAY['RUB'::text, 'VOTE'::text, 'XTR'::text, 'CHIP'::text]))),
+    CONSTRAINT orders_expected_amount_chk CHECK ((expected_amount >= 0))
+);
+
+-- The pending-expiry sweep scans (status, created_at).
+CREATE INDEX orders_status_created_at_idx ON payments.orders (status, created_at);
+
+-- The append-only operations ledger: every fund / spend / admin_grant / refund.
+-- `chips_delta` is signed (0 for a grant, which credits values not chips);
+-- `snapshot` records the sold atoms + price for a spend/grant. Never updated or
+-- deleted (a trigger enforces it); a reversal is a new `refund` row.
+CREATE TABLE payments.ledger (
+    ledger_id uuid NOT NULL,
+    account_id uuid NOT NULL,
+    kind text NOT NULL,
+    source text,
+    origin text,
+    chips_delta integer DEFAULT 0 NOT NULL,
+    product_id uuid,
+    order_id uuid,
+    provider text,
+    provider_payment_id text,
+    snapshot jsonb,
+    created_at timestamp with time zone DEFAULT now() NOT NULL,
+    CONSTRAINT ledger_pkey PRIMARY KEY (ledger_id),
+    CONSTRAINT ledger_product_fkey FOREIGN KEY (product_id)
+        REFERENCES payments.product (product_id),
+    CONSTRAINT ledger_order_fkey FOREIGN KEY (order_id)
+        REFERENCES payments.orders (order_id),
+    CONSTRAINT ledger_kind_chk
+        CHECK ((kind = ANY (ARRAY['fund'::text, 'spend'::text, 'admin_grant'::text, 'refund'::text]))),
+    CONSTRAINT ledger_source_chk
+        CHECK ((source IS NULL) OR (source = ANY (ARRAY['vk'::text, 'telegram'::text, 'direct'::text]))),
+    CONSTRAINT ledger_origin_chk
+        CHECK ((origin IS NULL) OR (origin = ANY (ARRAY['vk'::text, 'telegram'::text, 'direct'::text])))
+);
+
+-- Idempotency key: a provider callback credits at most once. Partial so rows
+-- without a provider payment id (spend/admin_grant) are unconstrained.
+CREATE UNIQUE INDEX ledger_provider_payment_idx
+    ON payments.ledger (provider, provider_payment_id)
+    WHERE provider_payment_id IS NOT NULL;
+
+-- +goose StatementBegin
+CREATE FUNCTION payments.ledger_append_only() RETURNS trigger LANGUAGE plpgsql AS $$
+BEGIN
+    RAISE EXCEPTION 'payments.ledger is append-only: % denied', TG_OP;
+END;
+$$;
+-- +goose StatementEnd
+
+CREATE TRIGGER ledger_no_mutation
+    BEFORE UPDATE OR DELETE ON payments.ledger
+    FOR EACH ROW EXECUTE FUNCTION payments.ledger_append_only();
+
+-- Materialised chip balance, segmented by funding source. A fast cache of the
+-- ledger, recomputable from it; created lazily on first fund (up to three rows
+-- per account, absent = zero).
+CREATE TABLE payments.balances (
+    account_id uuid NOT NULL,
+    source text NOT NULL,
+    chips integer DEFAULT 0 NOT NULL,
+    updated_at timestamp with time zone DEFAULT now() NOT NULL,
+    CONSTRAINT balances_pkey PRIMARY KEY (account_id, source),
+    CONSTRAINT balances_source_chk
+        CHECK ((source = ANY (ARRAY['vk'::text, 'telegram'::text, 'direct'::text]))),
+    CONSTRAINT balances_chips_chk CHECK ((chips >= 0))
+);
+
+-- Materialised benefits, segmented by the purchase origin. no-ads is a duration
+-- (ads_paid_until) plus a perpetual override (ads_forever); hints is a count.
+-- Created lazily on first grant/spend.
+CREATE TABLE payments.benefits (
+    account_id uuid NOT NULL,
+    origin text NOT NULL,
+    ads_paid_until timestamp with time zone,
+    ads_forever boolean DEFAULT false NOT NULL,
+    hints integer DEFAULT 0 NOT NULL,
+    updated_at timestamp with time zone DEFAULT now() NOT NULL,
+    CONSTRAINT benefits_pkey PRIMARY KEY (account_id, origin),
+    CONSTRAINT benefits_origin_chk
+        CHECK ((origin = ANY (ARRAY['vk'::text, 'telegram'::text, 'direct'::text]))),
+    CONSTRAINT benefits_hints_chk CHECK ((hints >= 0))
+);
+
+-- The single-row tunable config (durations in whole seconds — go-jet stringifies
+-- interval; payouts as counts). Edited in the admin console, no release needed.
+CREATE TABLE payments.config (
+    only_row boolean DEFAULT true NOT NULL,
+    rewarded_payout_chips integer DEFAULT 0 NOT NULL,
+    cooldown_global_seconds integer DEFAULT 300 NOT NULL,
+    cooldown_vs_ai_seconds integer DEFAULT 1800 NOT NULL,
+    cooldown_hint_seconds integer DEFAULT 60 NOT NULL,
+    order_ttl_seconds integer DEFAULT 1800 NOT NULL,
+    CONSTRAINT config_pkey PRIMARY KEY (only_row),
+    CONSTRAINT config_single_row_chk CHECK (only_row)
+);
+
+INSERT INTO payments.config (only_row) VALUES (true);
+
+-- Payment lifecycle events for the dispatcher (live stream / botlink / email).
+CREATE TABLE payments.payment_events (
+    event_id uuid NOT NULL,
+    account_id uuid NOT NULL,
+    order_id uuid,
+    type text NOT NULL,
+    payload jsonb,
+    created_at timestamp with time zone DEFAULT now() NOT NULL,
+    dispatched_at timestamp with time zone,
+    CONSTRAINT payment_events_pkey PRIMARY KEY (event_id),
+    CONSTRAINT payment_events_order_fkey FOREIGN KEY (order_id)
+        REFERENCES payments.orders (order_id),
+    CONSTRAINT payment_events_type_chk
+        CHECK ((type = ANY (ARRAY['succeeded'::text, 'failed'::text, 'refunded'::text])))
+);
+
+CREATE INDEX payment_events_dispatch_idx
+    ON payments.payment_events (dispatched_at)
+    WHERE dispatched_at IS NULL;
+
+-- Confine the payments role to this schema: ALL on its tables, nothing on
+-- backend. New tables added later inherit the grant via default privileges.
+GRANT ALL PRIVILEGES ON ALL TABLES IN SCHEMA payments TO payments;
+ALTER DEFAULT PRIVILEGES IN SCHEMA payments GRANT ALL ON TABLES TO payments;
+
+-- +goose Down
+
+ALTER DEFAULT PRIVILEGES IN SCHEMA payments REVOKE ALL ON TABLES FROM payments;
+DROP SCHEMA IF EXISTS payments CASCADE;
+
+-- +goose StatementBegin
+DO $$
+BEGIN
+    IF EXISTS (SELECT FROM pg_roles WHERE rolname = 'payments') THEN
+        EXECUTE 'DROP OWNED BY payments';
+        DROP ROLE payments;
+    END IF;
+END
+$$;
+-- +goose StatementEnd