Merge pull request 'feat(balance): schema migration v9 + service skeleton + AccountsPage (#138)' (#147) from issue-138-bilan-1a into main

CHANGELOG.fr.md

@@ -2,6 +2,9 @@
 
 ## [Non publié]
 
+### Ajouté
+- **Bilan — fondations du schéma et page Comptes** (route `/balance/accounts`) : première tranche de la nouvelle feature *Bilan*. La migration SQL v9 introduit 5 tables (`balance_categories`, `balance_accounts`, `balance_snapshots`, `balance_snapshot_lines`, `balance_account_transfers`) avec 7 index et seede 7 catégories standard — Encaisse, CELI, REER, Fonds commun, Autre (type simple) + Action et Cryptomonnaie (type coté). La colonne `currency` est verrouillée à `CAD` via une contrainte CHECK au MVP — le support multi-devises arrivera plus tard. La nouvelle page expose deux onglets : *Comptes* (CRUD complet sur les comptes de l'utilisateur, archivage soft plutôt que suppression dure pour préserver les snapshots historiques) et *Catégories* (renommer une catégorie, créer des catégories de type simple, supprimer celles créées par l'utilisateur — les catégories standard sont protégées). Couverture i18n FR/EN complète sous `balance.*`. Snapshots, transferts, rendements et price-fetching premium arriveront dans les prochaines issues ; pour l'instant la route est accessible directement par URL (pas encore d'entrée sidebar) (#138)
+
 ### Corrigé
 - **Rapport Zoom catégorie** (`/reports/category`) : la liste déroulante du combobox des catégories affiche désormais la liste complète dans un ordre hiérarchique DFS correct — chaque racine est émise avant ses descendants, et les frères et sœurs sont triés par `sort_order` puis nom affiché. Auparavant la liste était triée globalement par `sort_order` (via un `ORDER BY sort_order, name` SQL), ce qui entrelaçait des parents et enfants de sous-arbres différents partageant le même `sort_order`, d'où l'indentation incohérente et l'impression d'arbre cassé. La recherche filtrée (insensible aux accents) conserve le même comportement (#126)
 

CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## [Unreleased]
 
+### Added
+- **Balance sheet — schema foundation and accounts page** (route `/balance/accounts`): first slice of the upcoming *Bilan* feature. New SQL migration v9 introduces 5 tables (`balance_categories`, `balance_accounts`, `balance_snapshots`, `balance_snapshot_lines`, `balance_account_transfers`) with 7 indexes and seeds 7 standard categories — Cash, TFSA, RRSP, Mutual Fund, Other (simple kind) plus Stock and Crypto (priced kind). The `currency` column is hardcoded to `CAD` via a CHECK constraint at the MVP — multi-currency support will come in a later release. The new accounts page exposes two tabs: *Accounts* (full CRUD over the user's holdings, soft-archive instead of hard delete to preserve historic snapshots) and *Categories* (rename any category, create simple-kind ones, delete user-created ones — seeded categories are protected). The full FR/EN i18n coverage uses keys under `balance.*`. Snapshots, transfers, returns and the price-fetching premium remain to ship in upcoming issues; for now the route is reachable directly via URL (no sidebar entry yet) (#138)
+
 ### Fixed
 - **Category zoom report** (`/reports/category`): the category combobox dropdown now renders the full list in proper hierarchical DFS order — each root is emitted before its descendants, with siblings sorted by `sort_order` then display name. Previously the list was ordered by `sort_order` globally (from a SQL `ORDER BY sort_order, name`), which interleaved parents and children from different sub-trees that shared the same `sort_order`, producing scrambled indentation and a mis-leading tree. Filtering (accent-insensitive search) still behaves identically (#126)
 

src-tauri/src/database/balance_schema.sql

@@ -0,0 +1,153 @@
+-- Balance sheet schema (Bilan) — Migration v9
+-- Created: 2026-04-25
+-- Issue: #138 (Bilan #1a — Schema migration + balance.service skeleton + AccountsPage)
+--
+-- Adds 5 tables, 7 indexes, and seeds 7 standard categories (5 simple + 2 priced).
+-- Conventions aligned with consolidated_schema.sql:
+--   - INTEGER PRIMARY KEY AUTOINCREMENT
+--   - REAL for monetary amounts (matches transactions.amount)
+--   - snake_case
+--   - FK with explicit ON DELETE policies
+--   - is_* INTEGER NOT NULL DEFAULT for booleans
+--   - DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP for timestamps
+--
+-- MVP constraints (decisions-log + spec-decisions-bilan.md):
+--   - balance_accounts.currency hardcoded to 'CAD' via CHECK — v2 will lift this
+--   - balance_account_transfers.transaction_id ON DELETE RESTRICT (preserves
+--     reproducibility of Modified Dietz returns calculated on past periods)
+--   - balance_snapshot_lines kind invariants: (quantity, unit_price) both NULL
+--     (simple kind) OR both NOT NULL (priced kind)
+
+
+-- =========================================================================
+-- balance_categories — taxonomy of asset types
+-- =========================================================================
+-- Seeded with 7 standard categories (is_seed = 1). Users can add custom
+-- categories with their own kind ('simple' or 'priced'). Seeded categories
+-- can be renamed but never deleted.
+CREATE TABLE IF NOT EXISTS balance_categories (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    key TEXT NOT NULL UNIQUE,                    -- 'cash', 'tfsa', 'rrsp', 'fund', 'stock', 'crypto', 'other'
+    i18n_key TEXT NOT NULL,                      -- 'balance.category.cash', etc.
+    kind TEXT NOT NULL CHECK(kind IN ('simple','priced')),
+    sort_order INTEGER NOT NULL DEFAULT 0,
+    is_active INTEGER NOT NULL DEFAULT 1,
+    is_seed INTEGER NOT NULL DEFAULT 0
+);
+
+
+-- =========================================================================
+-- balance_accounts — user's specific holdings
+-- =========================================================================
+-- A "TFSA at Wealthsimple", a "BTC in Ledger", etc.
+-- For priced categories, `symbol` identifies the security/coin.
+-- For simple categories, `symbol` is NULL.
+-- MVP: currency hardcoded to 'CAD' — v2 lifts the CHECK and adds a rate table.
+CREATE TABLE IF NOT EXISTS balance_accounts (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    balance_category_id INTEGER NOT NULL,
+    name TEXT NOT NULL,
+    symbol TEXT,
+    currency TEXT NOT NULL DEFAULT 'CAD' CHECK(currency = 'CAD'),
+    notes TEXT,
+    is_active INTEGER NOT NULL DEFAULT 1,
+    archived_at DATETIME,
+    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (balance_category_id) REFERENCES balance_categories(id) ON DELETE RESTRICT
+);
+
+
+-- =========================================================================
+-- balance_snapshots — point-in-time captures
+-- =========================================================================
+-- One snapshot per `snapshot_date` (UNIQUE). Editing a snapshot = updating
+-- its lines, not creating a duplicate.
+CREATE TABLE IF NOT EXISTS balance_snapshots (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    snapshot_date DATE NOT NULL UNIQUE,
+    notes TEXT,
+    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP
+);
+
+
+-- =========================================================================
+-- balance_snapshot_lines — one row per (snapshot, account)
+-- =========================================================================
+-- Storage shape:
+--   - simple kind: value is set, quantity/unit_price are NULL
+--   - priced kind: quantity + unit_price are set, value = quantity * unit_price
+-- Stored denormalized (value always set, even for priced rows) so reports
+-- are reproducible without re-fetching prices and the user can override a
+-- fetched price.
+-- The CHECK enforces kind invariants at SQL level for direct-write safety.
+CREATE TABLE IF NOT EXISTS balance_snapshot_lines (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    snapshot_id INTEGER NOT NULL,
+    account_id INTEGER NOT NULL,
+    quantity REAL,
+    unit_price REAL,
+    value REAL NOT NULL,
+    price_source TEXT,                           -- 'manual' | 'maximus-api' | NULL for simple
+    price_fetched_at DATETIME,
+    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (snapshot_id) REFERENCES balance_snapshots(id) ON DELETE CASCADE,
+    FOREIGN KEY (account_id) REFERENCES balance_accounts(id) ON DELETE RESTRICT,
+    UNIQUE(snapshot_id, account_id),
+    CHECK (
+        (quantity IS NULL AND unit_price IS NULL)
+        OR (quantity IS NOT NULL AND unit_price IS NOT NULL)
+    )
+);
+
+
+-- =========================================================================
+-- balance_account_transfers — links transactions to accounts (capital flows)
+-- =========================================================================
+-- Used by the Modified Dietz return calculator (Issue #142 / Bilan #4) to
+-- separate contributions from gains. Direction follows the account's
+-- perspective: 'in' = capital added (deposit/buy), 'out' = capital removed
+-- (withdrawal/sell). The amount is taken from the linked transaction (no
+-- duplication).
+--
+-- transaction_id ON DELETE RESTRICT: preserves reproducibility of past
+-- Modified Dietz returns. The UI must force unlink before allowing the
+-- transaction to be deleted.
+CREATE TABLE IF NOT EXISTS balance_account_transfers (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    account_id INTEGER NOT NULL,
+    transaction_id INTEGER NOT NULL,
+    direction TEXT NOT NULL CHECK(direction IN ('in','out')),
+    notes TEXT,
+    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (account_id) REFERENCES balance_accounts(id) ON DELETE CASCADE,
+    FOREIGN KEY (transaction_id) REFERENCES transactions(id) ON DELETE RESTRICT,
+    UNIQUE(transaction_id, account_id)
+);
+
+
+-- =========================================================================
+-- Indexes (7 total)
+-- =========================================================================
+CREATE INDEX IF NOT EXISTS idx_balance_accounts_category ON balance_accounts(balance_category_id);
+CREATE INDEX IF NOT EXISTS idx_balance_accounts_active ON balance_accounts(is_active) WHERE is_active = 1;
+CREATE INDEX IF NOT EXISTS idx_balance_snapshot_lines_snapshot ON balance_snapshot_lines(snapshot_id);
+CREATE INDEX IF NOT EXISTS idx_balance_snapshot_lines_account ON balance_snapshot_lines(account_id);
+CREATE INDEX IF NOT EXISTS idx_balance_account_transfers_account ON balance_account_transfers(account_id);
+CREATE INDEX IF NOT EXISTS idx_balance_account_transfers_transaction ON balance_account_transfers(transaction_id);
+CREATE INDEX IF NOT EXISTS idx_balance_snapshots_date ON balance_snapshots(snapshot_date);
+
+
+-- =========================================================================
+-- Seed (7 standard categories — idempotent via INSERT OR IGNORE on `key`)
+-- =========================================================================
+INSERT OR IGNORE INTO balance_categories (key, i18n_key, kind, sort_order, is_seed) VALUES
+    ('cash',   'balance.category.cash',   'simple', 10, 1),
+    ('tfsa',   'balance.category.tfsa',   'simple', 20, 1),
+    ('rrsp',   'balance.category.rrsp',   'simple', 30, 1),
+    ('fund',   'balance.category.fund',   'simple', 40, 1),
+    ('other',  'balance.category.other',  'simple', 50, 1),
+    ('stock',  'balance.category.stock',  'priced', 60, 1),
+    ('crypto', 'balance.category.crypto', 'priced', 70, 1);

src-tauri/src/database/consolidated_schema.sql

@@ -181,6 +181,95 @@ CREATE INDEX IF NOT EXISTS idx_budget_entries_period ON budget_entries(year, mon
 CREATE INDEX IF NOT EXISTS idx_adjustment_entries_adjustment ON adjustment_entries(adjustment_id);
 CREATE INDEX IF NOT EXISTS idx_imported_files_source ON imported_files(source_id);
 
+-- ============================================================================
+-- Balance sheet (Bilan) — Migration v9 mirror for new profiles
+-- ============================================================================
+-- 5 tables + 7 indexes + seeded categories. Kept in sync with
+-- `balance_schema.sql` (the source of truth applied by Migration v9 in lib.rs).
+-- New profiles created from this consolidated schema get the balance feature
+-- preinstalled without needing to replay v9 separately.
+
+CREATE TABLE IF NOT EXISTS balance_categories (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    key TEXT NOT NULL UNIQUE,
+    i18n_key TEXT NOT NULL,
+    kind TEXT NOT NULL CHECK(kind IN ('simple','priced')),
+    sort_order INTEGER NOT NULL DEFAULT 0,
+    is_active INTEGER NOT NULL DEFAULT 1,
+    is_seed INTEGER NOT NULL DEFAULT 0
+);
+
+CREATE TABLE IF NOT EXISTS balance_accounts (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    balance_category_id INTEGER NOT NULL,
+    name TEXT NOT NULL,
+    symbol TEXT,
+    currency TEXT NOT NULL DEFAULT 'CAD' CHECK(currency = 'CAD'),
+    notes TEXT,
+    is_active INTEGER NOT NULL DEFAULT 1,
+    archived_at DATETIME,
+    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (balance_category_id) REFERENCES balance_categories(id) ON DELETE RESTRICT
+);
+
+CREATE TABLE IF NOT EXISTS balance_snapshots (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    snapshot_date DATE NOT NULL UNIQUE,
+    notes TEXT,
+    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE TABLE IF NOT EXISTS balance_snapshot_lines (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    snapshot_id INTEGER NOT NULL,
+    account_id INTEGER NOT NULL,
+    quantity REAL,
+    unit_price REAL,
+    value REAL NOT NULL,
+    price_source TEXT,
+    price_fetched_at DATETIME,
+    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (snapshot_id) REFERENCES balance_snapshots(id) ON DELETE CASCADE,
+    FOREIGN KEY (account_id) REFERENCES balance_accounts(id) ON DELETE RESTRICT,
+    UNIQUE(snapshot_id, account_id),
+    CHECK (
+        (quantity IS NULL AND unit_price IS NULL)
+        OR (quantity IS NOT NULL AND unit_price IS NOT NULL)
+    )
+);
+
+CREATE TABLE IF NOT EXISTS balance_account_transfers (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    account_id INTEGER NOT NULL,
+    transaction_id INTEGER NOT NULL,
+    direction TEXT NOT NULL CHECK(direction IN ('in','out')),
+    notes TEXT,
+    created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (account_id) REFERENCES balance_accounts(id) ON DELETE CASCADE,
+    FOREIGN KEY (transaction_id) REFERENCES transactions(id) ON DELETE RESTRICT,
+    UNIQUE(transaction_id, account_id)
+);
+
+CREATE INDEX IF NOT EXISTS idx_balance_accounts_category ON balance_accounts(balance_category_id);
+CREATE INDEX IF NOT EXISTS idx_balance_accounts_active ON balance_accounts(is_active) WHERE is_active = 1;
+CREATE INDEX IF NOT EXISTS idx_balance_snapshot_lines_snapshot ON balance_snapshot_lines(snapshot_id);
+CREATE INDEX IF NOT EXISTS idx_balance_snapshot_lines_account ON balance_snapshot_lines(account_id);
+CREATE INDEX IF NOT EXISTS idx_balance_account_transfers_account ON balance_account_transfers(account_id);
+CREATE INDEX IF NOT EXISTS idx_balance_account_transfers_transaction ON balance_account_transfers(transaction_id);
+CREATE INDEX IF NOT EXISTS idx_balance_snapshots_date ON balance_snapshots(snapshot_date);
+
+INSERT OR IGNORE INTO balance_categories (key, i18n_key, kind, sort_order, is_seed) VALUES
+    ('cash',   'balance.category.cash',   'simple', 10, 1),
+    ('tfsa',   'balance.category.tfsa',   'simple', 20, 1),
+    ('rrsp',   'balance.category.rrsp',   'simple', 30, 1),
+    ('fund',   'balance.category.fund',   'simple', 40, 1),
+    ('other',  'balance.category.other',  'simple', 50, 1),
+    ('stock',  'balance.category.stock',  'priced', 60, 1),
+    ('crypto', 'balance.category.crypto', 'priced', 70, 1);
+
 -- Default preferences (new profiles ship with the v1 IPC taxonomy)
 INSERT OR IGNORE INTO user_preferences (key, value) VALUES ('language', 'fr');
 INSERT OR IGNORE INTO user_preferences (key, value) VALUES ('theme', 'light');

src-tauri/src/database/mod.rs

@@ -1,3 +1,4 @@
 pub const SCHEMA: &str = include_str!("schema.sql");
 pub const SEED_CATEGORIES: &str = include_str!("seed_categories.sql");
 pub const CONSOLIDATED_SCHEMA: &str = include_str!("consolidated_schema.sql");
+pub const BALANCE_SCHEMA: &str = include_str!("balance_schema.sql");

src-tauri/src/lib.rs

@@ -95,6 +95,19 @@ pub fn run() {
             INSERT OR IGNORE INTO user_preferences (key, value) VALUES ('categories_schema_version', 'v2');",
             kind: MigrationKind::Up,
         },
+        // Migration v9 — Bilan (balance sheet) schema:
+        // 5 tables (balance_categories, balance_accounts, balance_snapshots,
+        // balance_snapshot_lines, balance_account_transfers) + 7 indexes +
+        // 7 seeded categories (5 simple + 2 priced).
+        // CHECK(currency = 'CAD') is hardcoded for the MVP (will be lifted in v2
+        // with a multi-currency rate table). FK transaction_id ON DELETE
+        // RESTRICT preserves reproducibility of Modified Dietz returns.
+        Migration {
+            version: 9,
+            description: "create balance schema",
+            sql: database::BALANCE_SCHEMA,
+            kind: MigrationKind::Up,
+        },
     ];
 
     tauri::Builder::default()
@@ -240,3 +253,443 @@ fn extract_query_param(url: &str, key: &str) -> Option<String> {
     }
     None
 }
+
+// =============================================================================
+// Tests for migration v9 — balance schema
+// -----------------------------------------------------------------------------
+// These tests apply `database::BALANCE_SCHEMA` (the SQL embedded in the v9
+// migration) on a fresh in-memory SQLite database and assert that:
+//   - the schema applies cleanly (all 5 tables + 7 indexes created)
+//   - the 7 seed categories are present (5 simple + 2 priced) with is_seed = 1
+//   - CHECK constraints reject invalid kind / direction / currency / kind invariants
+//   - UNIQUE constraints enforce snapshot_date / (snapshot_id,account_id) /
+//     (transaction_id,account_id) / category key
+//   - FK ON DELETE policies behave as expected (CASCADE on snapshot, RESTRICT
+//     on transaction_id and on category with linked accounts)
+//
+// rusqlite (0.32, bundled) is already a runtime dependency — no extra dev-dep
+// required. The migration v9 SQL is the source of truth; v1-v8 are not
+// required here because v9 is additive and only references the existing
+// `transactions` table for the FK on balance_account_transfers — we mirror
+// that with a minimal `transactions` table for the integration scenarios.
+#[cfg(test)]
+mod tests {
+    use rusqlite::Connection;
+
+    /// Apply the v9 schema on a fresh in-memory DB. Includes a minimal
+    /// `transactions` table because balance_account_transfers references it.
+    fn fresh_db() -> Connection {
+        let conn = Connection::open_in_memory().expect("open in-memory db");
+        // FKs must be enabled per-connection in SQLite.
+        conn.execute("PRAGMA foreign_keys = ON;", [])
+            .expect("enable FKs");
+        // Minimal transactions table mirroring the relevant columns the FK
+        // references (id is the only column we need at the SQL level).
+        conn.execute_batch(
+            "CREATE TABLE transactions (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                date DATE NOT NULL,
+                description TEXT NOT NULL,
+                amount REAL NOT NULL
+            );",
+        )
+        .expect("create stub transactions table");
+        conn.execute_batch(crate::database::BALANCE_SCHEMA)
+            .expect("apply BALANCE_SCHEMA");
+        conn
+    }
+
+    #[test]
+    fn migration_v9_applies_cleanly() {
+        let conn = fresh_db();
+        // 5 expected tables
+        let tables: Vec<String> = conn
+            .prepare(
+                "SELECT name FROM sqlite_master WHERE type='table' AND name LIKE 'balance_%' ORDER BY name",
+            )
+            .unwrap()
+            .query_map([], |row| row.get::<_, String>(0))
+            .unwrap()
+            .map(|r| r.unwrap())
+            .collect();
+        assert_eq!(
+            tables,
+            vec![
+                "balance_account_transfers",
+                "balance_accounts",
+                "balance_categories",
+                "balance_snapshot_lines",
+                "balance_snapshots",
+            ]
+        );
+        // 7 expected indexes
+        let index_count: i64 = conn
+            .query_row(
+                "SELECT COUNT(*) FROM sqlite_master WHERE type='index' AND name LIKE 'idx_balance_%'",
+                [],
+                |row| row.get(0),
+            )
+            .unwrap();
+        assert_eq!(index_count, 7);
+    }
+
+    #[test]
+    fn migration_v9_seeds_7_categories() {
+        let conn = fresh_db();
+        let count: i64 = conn
+            .query_row(
+                "SELECT COUNT(*) FROM balance_categories WHERE is_seed = 1",
+                [],
+                |row| row.get(0),
+            )
+            .unwrap();
+        assert_eq!(count, 7);
+
+        let simple_count: i64 = conn
+            .query_row(
+                "SELECT COUNT(*) FROM balance_categories WHERE kind = 'simple' AND is_seed = 1",
+                [],
+                |row| row.get(0),
+            )
+            .unwrap();
+        assert_eq!(simple_count, 5);
+
+        let priced_count: i64 = conn
+            .query_row(
+                "SELECT COUNT(*) FROM balance_categories WHERE kind = 'priced' AND is_seed = 1",
+                [],
+                |row| row.get(0),
+            )
+            .unwrap();
+        assert_eq!(priced_count, 2);
+
+        // Seeded keys are stable
+        let stock_kind: String = conn
+            .query_row(
+                "SELECT kind FROM balance_categories WHERE key = 'stock'",
+                [],
+                |row| row.get(0),
+            )
+            .unwrap();
+        assert_eq!(stock_kind, "priced");
+    }
+
+    #[test]
+    fn migration_v9_rejects_non_cad_currency() {
+        let conn = fresh_db();
+        // 'cash' category exists from seed; try to insert a non-CAD account.
+        let result = conn.execute(
+            "INSERT INTO balance_accounts (balance_category_id, name, currency)
+             VALUES ((SELECT id FROM balance_categories WHERE key='cash'), 'USD account', 'USD')",
+            [],
+        );
+        assert!(
+            result.is_err(),
+            "CHECK(currency='CAD') should reject 'USD'"
+        );
+        let err_msg = result.unwrap_err().to_string();
+        assert!(err_msg.to_lowercase().contains("check"));
+    }
+
+    #[test]
+    fn migration_v9_accepts_default_cad_currency() {
+        let conn = fresh_db();
+        let inserted = conn
+            .execute(
+                "INSERT INTO balance_accounts (balance_category_id, name)
+                 VALUES ((SELECT id FROM balance_categories WHERE key='cash'), 'Encaisse')",
+                [],
+            )
+            .expect("CAD default insert should succeed");
+        assert_eq!(inserted, 1);
+    }
+
+    #[test]
+    fn migration_v9_rejects_invalid_kind() {
+        let conn = fresh_db();
+        let result = conn.execute(
+            "INSERT INTO balance_categories (key, i18n_key, kind) VALUES ('bogus', 'x.bogus', 'unknown')",
+            [],
+        );
+        assert!(result.is_err(), "kind CHECK should reject 'unknown'");
+    }
+
+    #[test]
+    fn migration_v9_unique_snapshot_date() {
+        let conn = fresh_db();
+        conn.execute(
+            "INSERT INTO balance_snapshots (snapshot_date) VALUES ('2026-04-25')",
+            [],
+        )
+        .unwrap();
+        let result = conn.execute(
+            "INSERT INTO balance_snapshots (snapshot_date) VALUES ('2026-04-25')",
+            [],
+        );
+        assert!(result.is_err(), "UNIQUE(snapshot_date) should reject dup");
+    }
+
+    #[test]
+    fn migration_v9_kind_invariants_check() {
+        let conn = fresh_db();
+        // Setup: a snapshot + an account
+        conn.execute(
+            "INSERT INTO balance_snapshots (snapshot_date) VALUES ('2026-04-25')",
+            [],
+        )
+        .unwrap();
+        conn.execute(
+            "INSERT INTO balance_accounts (balance_category_id, name)
+             VALUES ((SELECT id FROM balance_categories WHERE key='cash'), 'Encaisse')",
+            [],
+        )
+        .unwrap();
+        let snap_id: i64 = conn
+            .query_row("SELECT id FROM balance_snapshots LIMIT 1", [], |r| r.get(0))
+            .unwrap();
+        let acct_id: i64 = conn
+            .query_row("SELECT id FROM balance_accounts LIMIT 1", [], |r| r.get(0))
+            .unwrap();
+
+        // OK: simple kind (quantity + unit_price both NULL)
+        conn.execute(
+            "INSERT INTO balance_snapshot_lines (snapshot_id, account_id, value)
+             VALUES (?1, ?2, 1234.56)",
+            rusqlite::params![snap_id, acct_id],
+        )
+        .expect("simple kind row (qty/price both NULL) should be accepted");
+
+        // OK: priced kind (both set) — needs second account on a priced category
+        conn.execute(
+            "INSERT INTO balance_accounts (balance_category_id, name, symbol)
+             VALUES ((SELECT id FROM balance_categories WHERE key='stock'), 'AAPL', 'AAPL')",
+            [],
+        )
+        .unwrap();
+        let acct2_id: i64 = conn
+            .query_row(
+                "SELECT id FROM balance_accounts WHERE name='AAPL'",
+                [],
+                |r| r.get(0),
+            )
+            .unwrap();
+        conn.execute(
+            "INSERT INTO balance_snapshot_lines (snapshot_id, account_id, quantity, unit_price, value)
+             VALUES (?1, ?2, 10.0, 200.0, 2000.0)",
+            rusqlite::params![snap_id, acct2_id],
+        )
+        .expect("priced kind row (both set) should be accepted");
+
+        // KO: only quantity set, unit_price NULL → CHECK violation
+        let bad = conn.execute(
+            "INSERT INTO balance_snapshot_lines (snapshot_id, account_id, quantity, value)
+             VALUES (?1, ?2, 10.0, 0.0)",
+            rusqlite::params![snap_id, acct_id],
+        );
+        assert!(
+            bad.is_err(),
+            "kind invariants CHECK should reject (qty set, price NULL)"
+        );
+
+        // KO: only unit_price set, quantity NULL → CHECK violation
+        let bad2 = conn.execute(
+            "INSERT INTO balance_snapshot_lines (snapshot_id, account_id, unit_price, value)
+             VALUES (?1, ?2, 200.0, 0.0)",
+            rusqlite::params![snap_id, acct_id],
+        );
+        assert!(
+            bad2.is_err(),
+            "kind invariants CHECK should reject (price set, qty NULL)"
+        );
+    }
+
+    #[test]
+    fn migration_v9_unique_snapshot_account_pair() {
+        let conn = fresh_db();
+        conn.execute(
+            "INSERT INTO balance_snapshots (snapshot_date) VALUES ('2026-04-25')",
+            [],
+        )
+        .unwrap();
+        conn.execute(
+            "INSERT INTO balance_accounts (balance_category_id, name)
+             VALUES ((SELECT id FROM balance_categories WHERE key='cash'), 'Encaisse')",
+            [],
+        )
+        .unwrap();
+        let snap_id: i64 = conn
+            .query_row("SELECT id FROM balance_snapshots LIMIT 1", [], |r| r.get(0))
+            .unwrap();
+        let acct_id: i64 = conn
+            .query_row("SELECT id FROM balance_accounts LIMIT 1", [], |r| r.get(0))
+            .unwrap();
+        conn.execute(
+            "INSERT INTO balance_snapshot_lines (snapshot_id, account_id, value)
+             VALUES (?1, ?2, 100.0)",
+            rusqlite::params![snap_id, acct_id],
+        )
+        .unwrap();
+        let dup = conn.execute(
+            "INSERT INTO balance_snapshot_lines (snapshot_id, account_id, value)
+             VALUES (?1, ?2, 200.0)",
+            rusqlite::params![snap_id, acct_id],
+        );
+        assert!(dup.is_err(), "UNIQUE(snapshot_id, account_id) should reject dup");
+    }
+
+    #[test]
+    fn migration_v9_fk_cascade_on_snapshot_delete() {
+        let conn = fresh_db();
+        conn.execute(
+            "INSERT INTO balance_snapshots (snapshot_date) VALUES ('2026-04-25')",
+            [],
+        )
+        .unwrap();
+        conn.execute(
+            "INSERT INTO balance_accounts (balance_category_id, name)
+             VALUES ((SELECT id FROM balance_categories WHERE key='cash'), 'Encaisse')",
+            [],
+        )
+        .unwrap();
+        let snap_id: i64 = conn
+            .query_row("SELECT id FROM balance_snapshots LIMIT 1", [], |r| r.get(0))
+            .unwrap();
+        let acct_id: i64 = conn
+            .query_row("SELECT id FROM balance_accounts LIMIT 1", [], |r| r.get(0))
+            .unwrap();
+        conn.execute(
+            "INSERT INTO balance_snapshot_lines (snapshot_id, account_id, value)
+             VALUES (?1, ?2, 100.0)",
+            rusqlite::params![snap_id, acct_id],
+        )
+        .unwrap();
+        conn.execute(
+            "DELETE FROM balance_snapshots WHERE id = ?1",
+            rusqlite::params![snap_id],
+        )
+        .expect("delete snapshot should cascade");
+        let remaining: i64 = conn
+            .query_row("SELECT COUNT(*) FROM balance_snapshot_lines", [], |r| r.get(0))
+            .unwrap();
+        assert_eq!(remaining, 0, "snapshot delete should cascade lines");
+    }
+
+    #[test]
+    fn migration_v9_fk_restrict_on_transaction_delete() {
+        let conn = fresh_db();
+        conn.execute(
+            "INSERT INTO balance_accounts (balance_category_id, name)
+             VALUES ((SELECT id FROM balance_categories WHERE key='cash'), 'Encaisse')",
+            [],
+        )
+        .unwrap();
+        conn.execute(
+            "INSERT INTO transactions (date, description, amount) VALUES ('2026-04-25', 'Deposit', 1000.0)",
+            [],
+        )
+        .unwrap();
+        let acct_id: i64 = conn
+            .query_row("SELECT id FROM balance_accounts LIMIT 1", [], |r| r.get(0))
+            .unwrap();
+        let tx_id: i64 = conn
+            .query_row("SELECT id FROM transactions LIMIT 1", [], |r| r.get(0))
+            .unwrap();
+        conn.execute(
+            "INSERT INTO balance_account_transfers (account_id, transaction_id, direction)
+             VALUES (?1, ?2, 'in')",
+            rusqlite::params![acct_id, tx_id],
+        )
+        .unwrap();
+
+        // Attempting to delete the linked transaction must be rejected (RESTRICT)
+        let result = conn.execute("DELETE FROM transactions WHERE id = ?1", rusqlite::params![tx_id]);
+        assert!(
+            result.is_err(),
+            "FK RESTRICT should block deleting linked transaction"
+        );
+
+        // Once the transfer is removed, deletion is allowed again
+        conn.execute(
+            "DELETE FROM balance_account_transfers WHERE transaction_id = ?1",
+            rusqlite::params![tx_id],
+        )
+        .unwrap();
+        conn.execute("DELETE FROM transactions WHERE id = ?1", rusqlite::params![tx_id])
+            .expect("after unlink, transaction can be deleted");
+    }
+
+    #[test]
+    fn migration_v9_fk_restrict_on_category_with_accounts() {
+        let conn = fresh_db();
+        conn.execute(
+            "INSERT INTO balance_accounts (balance_category_id, name)
+             VALUES ((SELECT id FROM balance_categories WHERE key='cash'), 'Encaisse')",
+            [],
+        )
+        .unwrap();
+        // Try to delete the seeded 'cash' category while an account references it
+        let result = conn.execute(
+            "DELETE FROM balance_categories WHERE key = 'cash'",
+            [],
+        );
+        assert!(
+            result.is_err(),
+            "FK RESTRICT should block deleting category with linked accounts"
+        );
+    }
+
+    #[test]
+    fn migration_v9_unique_transaction_account_transfer() {
+        let conn = fresh_db();
+        conn.execute(
+            "INSERT INTO balance_accounts (balance_category_id, name)
+             VALUES ((SELECT id FROM balance_categories WHERE key='cash'), 'Encaisse')",
+            [],
+        )
+        .unwrap();
+        conn.execute(
+            "INSERT INTO transactions (date, description, amount) VALUES ('2026-04-25', 'Deposit', 1000.0)",
+            [],
+        )
+        .unwrap();
+        let acct_id: i64 = conn
+            .query_row("SELECT id FROM balance_accounts LIMIT 1", [], |r| r.get(0))
+            .unwrap();
+        let tx_id: i64 = conn
+            .query_row("SELECT id FROM transactions LIMIT 1", [], |r| r.get(0))
+            .unwrap();
+        conn.execute(
+            "INSERT INTO balance_account_transfers (account_id, transaction_id, direction)
+             VALUES (?1, ?2, 'in')",
+            rusqlite::params![acct_id, tx_id],
+        )
+        .unwrap();
+        let dup = conn.execute(
+            "INSERT INTO balance_account_transfers (account_id, transaction_id, direction)
+             VALUES (?1, ?2, 'out')",
+            rusqlite::params![acct_id, tx_id],
+        );
+        assert!(
+            dup.is_err(),
+            "UNIQUE(transaction_id, account_id) should reject dup"
+        );
+    }
+
+    #[test]
+    fn migration_v9_seed_idempotent_on_replay() {
+        // The migration uses `INSERT OR IGNORE` keyed by `key`, so applying
+        // the schema twice on the same DB must not duplicate seeded rows.
+        let conn = fresh_db();
+        conn.execute_batch(crate::database::BALANCE_SCHEMA)
+            .expect("apply BALANCE_SCHEMA twice");
+        let count: i64 = conn
+            .query_row(
+                "SELECT COUNT(*) FROM balance_categories WHERE is_seed = 1",
+                [],
+                |row| row.get(0),
+            )
+            .unwrap();
+        assert_eq!(count, 7, "seed must remain idempotent on replay");
+    }
+}
+

src/App.tsx

@@ -16,6 +16,7 @@ import ReportsComparePage from "./pages/ReportsComparePage";
 import ReportsCategoryPage from "./pages/ReportsCategoryPage";
 import ReportsCartesPage from "./pages/ReportsCartesPage";
 import SettingsPage from "./pages/SettingsPage";
+import AccountsPage from "./pages/AccountsPage";
 import CategoriesStandardGuidePage from "./pages/CategoriesStandardGuidePage";
 import CategoriesMigrationPage from "./pages/CategoriesMigrationPage";
 import DocsPage from "./pages/DocsPage";
@@ -114,6 +115,7 @@ export default function App() {
           <Route path="/reports/category" element={<ReportsCategoryPage />} />
           <Route path="/reports/cartes" element={<ReportsCartesPage />} />
           <Route path="/settings" element={<SettingsPage />} />
+          <Route path="/balance/accounts" element={<AccountsPage />} />
           <Route
             path="/settings/categories/standard"
             element={<CategoriesStandardGuidePage />}

src/components/balance/AccountForm.tsx

@@ -0,0 +1,229 @@
+// AccountForm — variant=account (Issue #138 / Bilan #1a).
+//
+// The category variant lands in Issue #140 (Bilan #2) when the priced-kind
+// switch becomes available. For now this component focuses on creating /
+// editing a `balance_account` record bound to an existing category.
+
+import { FormEvent, useEffect, useState } from "react";
+import { useTranslation } from "react-i18next";
+import type {
+  BalanceAccount,
+  BalanceCategory,
+} from "../../shared/types";
+import type {
+  CreateBalanceAccountInput,
+  UpdateBalanceAccountInput,
+} from "../../services/balance.service";
+
+export interface AccountFormValues {
+  balance_category_id: number;
+  name: string;
+  symbol: string;
+  notes: string;
+}
+
+interface Props {
+  /** When provided, the form is in edit mode; otherwise creation. */
+  initialAccount?: BalanceAccount | null;
+  categories: BalanceCategory[];
+  isSaving: boolean;
+  onSubmit: (
+    values: CreateBalanceAccountInput | UpdateBalanceAccountInput
+  ) => Promise<void> | void;
+  onCancel: () => void;
+}
+
+function defaultValues(
+  initial: BalanceAccount | null | undefined,
+  categories: BalanceCategory[]
+): AccountFormValues {
+  if (initial) {
+    return {
+      balance_category_id: initial.balance_category_id,
+      name: initial.name,
+      symbol: initial.symbol ?? "",
+      notes: initial.notes ?? "",
+    };
+  }
+  // First active category as a sane default
+  const first = categories.find((c) => c.is_active) ?? categories[0];
+  return {
+    balance_category_id: first?.id ?? 0,
+    name: "",
+    symbol: "",
+    notes: "",
+  };
+}
+
+export default function AccountForm({
+  initialAccount,
+  categories,
+  isSaving,
+  onSubmit,
+  onCancel,
+}: Props) {
+  const { t } = useTranslation();
+  const [values, setValues] = useState<AccountFormValues>(() =>
+    defaultValues(initialAccount, categories)
+  );
+  const [touched, setTouched] = useState(false);
+
+  // Reset form when target account changes (edit different row).
+  useEffect(() => {
+    setValues(defaultValues(initialAccount, categories));
+    setTouched(false);
+  }, [initialAccount, categories]);
+
+  const isEditing = !!initialAccount;
+  const selectedCategory = categories.find(
+    (c) => c.id === values.balance_category_id
+  );
+  const isPriced = selectedCategory?.kind === "priced";
+  const trimmedName = values.name.trim();
+  const nameInvalid = touched && trimmedName.length === 0;
+
+  const handleSubmit = async (e: FormEvent) => {
+    e.preventDefault();
+    setTouched(true);
+    if (!trimmedName) return;
+
+    const payload: CreateBalanceAccountInput = {
+      balance_category_id: values.balance_category_id,
+      name: trimmedName,
+      symbol: values.symbol.trim() || null,
+      notes: values.notes.trim() || null,
+    };
+
+    if (isEditing) {
+      const updatePayload: UpdateBalanceAccountInput = {
+        balance_category_id: payload.balance_category_id,
+        name: payload.name,
+        symbol: payload.symbol,
+        notes: payload.notes,
+      };
+      await onSubmit(updatePayload);
+    } else {
+      await onSubmit(payload);
+    }
+  };
+
+  const renderCategoryLabel = (cat: BalanceCategory) =>
+    t(cat.i18n_key, { defaultValue: cat.key });
+
+  return (
+    <form onSubmit={handleSubmit} className="flex flex-col gap-4">
+      <div>
+        <label className="block text-sm font-medium mb-1" htmlFor="account-category">
+          {t("balance.account.form.category")}
+        </label>
+        <select
+          id="account-category"
+          value={values.balance_category_id}
+          onChange={(e) =>
+            setValues({
+              ...values,
+              balance_category_id: Number(e.target.value),
+            })
+          }
+          className="w-full px-3 py-2 rounded-lg border border-[var(--border)] bg-[var(--card)] text-sm focus:outline-none focus:ring-1 focus:ring-[var(--primary)]"
+        >
+          {categories.length === 0 ? (
+            <option value={0}>{t("balance.account.form.noCategory")}</option>
+          ) : (
+            categories.map((cat) => (
+              <option key={cat.id} value={cat.id}>
+                {renderCategoryLabel(cat)}
+              </option>
+            ))
+          )}
+        </select>
+      </div>
+
+      <div>
+        <label className="block text-sm font-medium mb-1" htmlFor="account-name">
+          {t("balance.account.form.name")}
+        </label>
+        <input
+          id="account-name"
+          type="text"
+          value={values.name}
+          onChange={(e) => setValues({ ...values, name: e.target.value })}
+          onBlur={() => setTouched(true)}
+          className={`w-full px-3 py-2 rounded-lg border bg-[var(--card)] text-sm focus:outline-none focus:ring-1 focus:ring-[var(--primary)] ${
+            nameInvalid
+              ? "border-[var(--negative)]"
+              : "border-[var(--border)]"
+          }`}
+          autoFocus
+          autoComplete="off"
+        />
+        {nameInvalid && (
+          <p className="mt-1 text-xs text-[var(--negative)]">
+            {t("balance.account.form.nameRequired")}
+          </p>
+        )}
+      </div>
+
+      <div>
+        <label className="block text-sm font-medium mb-1" htmlFor="account-symbol">
+          {t("balance.account.form.symbol")}
+          {isPriced && (
+            <span className="ml-1 text-xs text-[var(--muted-foreground)]">
+              ({t("balance.account.form.symbolPricedHint")})
+            </span>
+          )}
+        </label>
+        <input
+          id="account-symbol"
+          type="text"
+          value={values.symbol}
+          onChange={(e) => setValues({ ...values, symbol: e.target.value })}
+          placeholder={
+            isPriced
+              ? t("balance.account.form.symbolPlaceholderPriced")
+              : t("balance.account.form.symbolPlaceholderSimple")
+          }
+          className="w-full px-3 py-2 rounded-lg border border-[var(--border)] bg-[var(--card)] text-sm focus:outline-none focus:ring-1 focus:ring-[var(--primary)]"
+          autoComplete="off"
+        />
+      </div>
+
+      <div>
+        <label className="block text-sm font-medium mb-1" htmlFor="account-notes">
+          {t("balance.account.form.notes")}
+        </label>
+        <textarea
+          id="account-notes"
+          value={values.notes}
+          onChange={(e) => setValues({ ...values, notes: e.target.value })}
+          rows={2}
+          className="w-full px-3 py-2 rounded-lg border border-[var(--border)] bg-[var(--card)] text-sm focus:outline-none focus:ring-1 focus:ring-[var(--primary)] resize-none"
+        />
+      </div>
+
+      <p className="text-xs text-[var(--muted-foreground)]">
+        {t("balance.account.form.currencyMvpNotice")}
+      </p>
+
+      <div className="flex justify-end gap-2">
+        <button
+          type="button"
+          onClick={onCancel}
+          disabled={isSaving}
+          className="px-4 py-2 rounded-lg border border-[var(--border)] text-sm hover:bg-[var(--muted)] disabled:opacity-50"
+        >
+          {t("common.cancel")}
+        </button>
+        <button
+          type="submit"
+          disabled={isSaving || !trimmedName || categories.length === 0}
+          className="px-4 py-2 rounded-lg bg-[var(--primary)] text-white text-sm font-medium hover:opacity-90 disabled:opacity-50"
+        >
+          {isEditing
+            ? t("balance.account.form.save")
+            : t("balance.account.form.create")}
+        </button>
+      </div>
+    </form>
+  );
+}

src/hooks/useBalanceAccounts.ts

@@ -0,0 +1,276 @@
+// useBalanceAccounts — scoped useReducer hook backing AccountsPage.
+//
+// Domain coverage (per spec-plan-bilan.md v2): the AccountsPage CRUD over
+// `balance_accounts` AND `balance_categories`. Snapshots, lines, transfers,
+// and returns are out of scope here — they belong to `useSnapshotEditor`
+// (Issue #146 / Bilan #1b) and `useBalanceOverview` (Issue #141 / Bilan #3).
+
+import { useReducer, useCallback, useEffect, useRef } from "react";
+import type {
+  BalanceAccountWithCategory,
+  BalanceCategory,
+  BalanceCategoryKind,
+} from "../shared/types";
+import {
+  listBalanceAccounts,
+  listBalanceCategories,
+  createBalanceAccount,
+  updateBalanceAccount,
+  archiveBalanceAccount,
+  unarchiveBalanceAccount,
+  createBalanceCategory,
+  updateBalanceCategory,
+  deleteBalanceCategory,
+  BalanceServiceError,
+  type CreateBalanceAccountInput,
+  type CreateBalanceCategoryInput,
+  type UpdateBalanceAccountInput,
+  type UpdateBalanceCategoryInput,
+} from "../services/balance.service";
+
+interface State {
+  accounts: BalanceAccountWithCategory[];
+  categories: BalanceCategory[];
+  includeArchived: boolean;
+  isLoading: boolean;
+  isSaving: boolean;
+  error: string | null;
+  /** Stable error code for UIs that want to localize via i18n (e.g. seed protection). */
+  errorCode: string | null;
+}
+
+type Action =
+  | { type: "SET_LOADING"; payload: boolean }
+  | { type: "SET_SAVING"; payload: boolean }
+  | { type: "SET_ERROR"; payload: { message: string | null; code: string | null } }
+  | {
+      type: "SET_DATA";
+      payload: {
+        accounts: BalanceAccountWithCategory[];
+        categories: BalanceCategory[];
+      };
+    }
+  | { type: "SET_INCLUDE_ARCHIVED"; payload: boolean };
+
+function initialState(): State {
+  return {
+    accounts: [],
+    categories: [],
+    includeArchived: false,
+    isLoading: false,
+    isSaving: false,
+    error: null,
+    errorCode: null,
+  };
+}
+
+function reducer(state: State, action: Action): State {
+  switch (action.type) {
+    case "SET_LOADING":
+      return { ...state, isLoading: action.payload };
+    case "SET_SAVING":
+      return { ...state, isSaving: action.payload };
+    case "SET_ERROR":
+      return {
+        ...state,
+        error: action.payload.message,
+        errorCode: action.payload.code,
+        isLoading: false,
+        isSaving: false,
+      };
+    case "SET_DATA":
+      return {
+        ...state,
+        accounts: action.payload.accounts,
+        categories: action.payload.categories,
+        isLoading: false,
+        error: null,
+        errorCode: null,
+      };
+    case "SET_INCLUDE_ARCHIVED":
+      return { ...state, includeArchived: action.payload };
+    default:
+      return state;
+  }
+}
+
+function describeError(e: unknown): { message: string; code: string | null } {
+  if (e instanceof BalanceServiceError) {
+    return { message: e.message, code: e.code };
+  }
+  return {
+    message: e instanceof Error ? e.message : String(e),
+    code: null,
+  };
+}
+
+export function useBalanceAccounts() {
+  const [state, dispatch] = useReducer(reducer, undefined, initialState);
+  const fetchIdRef = useRef(0);
+
+  const refreshData = useCallback(async (includeArchived: boolean) => {
+    const fetchId = ++fetchIdRef.current;
+    dispatch({ type: "SET_LOADING", payload: true });
+    dispatch({ type: "SET_ERROR", payload: { message: null, code: null } });
+    try {
+      const [accounts, categories] = await Promise.all([
+        listBalanceAccounts({ includeArchived }),
+        listBalanceCategories(),
+      ]);
+      if (fetchId !== fetchIdRef.current) return;
+      dispatch({ type: "SET_DATA", payload: { accounts, categories } });
+    } catch (e) {
+      if (fetchId !== fetchIdRef.current) return;
+      dispatch({ type: "SET_ERROR", payload: describeError(e) });
+    }
+  }, []);
+
+  useEffect(() => {
+    refreshData(state.includeArchived);
+  }, [state.includeArchived, refreshData]);
+
+  const setIncludeArchived = useCallback((next: boolean) => {
+    dispatch({ type: "SET_INCLUDE_ARCHIVED", payload: next });
+  }, []);
+
+  // ---------------------------------------------------------------------------
+  // Account mutations
+  // ---------------------------------------------------------------------------
+
+  const addAccount = useCallback(
+    async (input: CreateBalanceAccountInput) => {
+      dispatch({ type: "SET_SAVING", payload: true });
+      try {
+        await createBalanceAccount(input);
+        await refreshData(state.includeArchived);
+      } catch (e) {
+        dispatch({ type: "SET_ERROR", payload: describeError(e) });
+        throw e;
+      } finally {
+        dispatch({ type: "SET_SAVING", payload: false });
+      }
+    },
+    [state.includeArchived, refreshData]
+  );
+
+  const editAccount = useCallback(
+    async (id: number, input: UpdateBalanceAccountInput) => {
+      dispatch({ type: "SET_SAVING", payload: true });
+      try {
+        await updateBalanceAccount(id, input);
+        await refreshData(state.includeArchived);
+      } catch (e) {
+        dispatch({ type: "SET_ERROR", payload: describeError(e) });
+        throw e;
+      } finally {
+        dispatch({ type: "SET_SAVING", payload: false });
+      }
+    },
+    [state.includeArchived, refreshData]
+  );
+
+  const archiveAccount = useCallback(
+    async (id: number) => {
+      dispatch({ type: "SET_SAVING", payload: true });
+      try {
+        await archiveBalanceAccount(id);
+        await refreshData(state.includeArchived);
+      } catch (e) {
+        dispatch({ type: "SET_ERROR", payload: describeError(e) });
+        throw e;
+      } finally {
+        dispatch({ type: "SET_SAVING", payload: false });
+      }
+    },
+    [state.includeArchived, refreshData]
+  );
+
+  const unarchiveAccount = useCallback(
+    async (id: number) => {
+      dispatch({ type: "SET_SAVING", payload: true });
+      try {
+        await unarchiveBalanceAccount(id);
+        await refreshData(state.includeArchived);
+      } catch (e) {
+        dispatch({ type: "SET_ERROR", payload: describeError(e) });
+        throw e;
+      } finally {
+        dispatch({ type: "SET_SAVING", payload: false });
+      }
+    },
+    [state.includeArchived, refreshData]
+  );
+
+  // ---------------------------------------------------------------------------
+  // Category mutations
+  // ---------------------------------------------------------------------------
+
+  /**
+   * Issue #138 keeps the AccountsPage Categories tab to user-created
+   * `simple` kind only. The priced creation UI lands in #140 — until then,
+   * callers should pass kind = 'simple'.
+   */
+  const addCategory = useCallback(
+    async (input: CreateBalanceCategoryInput) => {
+      const kind: BalanceCategoryKind = input.kind ?? "simple";
+      dispatch({ type: "SET_SAVING", payload: true });
+      try {
+        await createBalanceCategory({ ...input, kind });
+        await refreshData(state.includeArchived);
+      } catch (e) {
+        dispatch({ type: "SET_ERROR", payload: describeError(e) });
+        throw e;
+      } finally {
+        dispatch({ type: "SET_SAVING", payload: false });
+      }
+    },
+    [state.includeArchived, refreshData]
+  );
+
+  const editCategory = useCallback(
+    async (id: number, input: UpdateBalanceCategoryInput) => {
+      dispatch({ type: "SET_SAVING", payload: true });
+      try {
+        await updateBalanceCategory(id, input);
+        await refreshData(state.includeArchived);
+      } catch (e) {
+        dispatch({ type: "SET_ERROR", payload: describeError(e) });
+        throw e;
+      } finally {
+        dispatch({ type: "SET_SAVING", payload: false });
+      }
+    },
+    [state.includeArchived, refreshData]
+  );
+
+  const removeCategory = useCallback(
+    async (id: number) => {
+      dispatch({ type: "SET_SAVING", payload: true });
+      try {
+        await deleteBalanceCategory(id);
+        await refreshData(state.includeArchived);
+      } catch (e) {
+        dispatch({ type: "SET_ERROR", payload: describeError(e) });
+        throw e;
+      } finally {
+        dispatch({ type: "SET_SAVING", payload: false });
+      }
+    },
+    [state.includeArchived, refreshData]
+  );
+
+  return {
+    state,
+    setIncludeArchived,
+    refresh: () => refreshData(state.includeArchived),
+    // Account ops
+    addAccount,
+    editAccount,
+    archiveAccount,
+    unarchiveAccount,
+    // Category ops
+    addCategory,
+    editCategory,
+    removeCategory,
+  };
+}

src/i18n/locales/en.json

@@ -1449,5 +1449,100 @@
         }
       }
     }
+  },
+  "balance": {
+    "accountsPage": {
+      "title": "Balance accounts",
+      "tabs": {
+        "accounts": "Accounts",
+        "categories": "Categories"
+      },
+      "newAccount": "New account",
+      "includeArchived": "Show archived accounts",
+      "empty": "No accounts yet. Click “New account” to start."
+    },
+    "account": {
+      "fields": {
+        "name": "Name",
+        "category": "Category",
+        "symbol": "Symbol",
+        "currency": "Currency",
+        "status": "Status",
+        "actions": "Actions"
+      },
+      "status": {
+        "active": "Active",
+        "archived": "Archived"
+      },
+      "actions": {
+        "archive": "Archive",
+        "unarchive": "Restore"
+      },
+      "form": {
+        "createTitle": "New account",
+        "editTitle": "Edit account",
+        "category": "Category",
+        "noCategory": "(no category available)",
+        "name": "Account name",
+        "nameRequired": "Name is required.",
+        "symbol": "Symbol",
+        "symbolPricedHint": "required for priced categories",
+        "symbolPlaceholderSimple": "Optional",
+        "symbolPlaceholderPriced": "e.g. AAPL, BTC-USD",
+        "notes": "Notes",
+        "currencyMvpNotice": "At the MVP, all accounts are in CAD. Multi-currency support will land in a later version.",
+        "save": "Save",
+        "create": "Create account"
+      }
+    },
+    "category": {
+      "intro": "Seeded categories (TFSA, RRSP, Cash, etc.) ship with the app. You can create your own for special cases.",
+      "fields": {
+        "name": "Name",
+        "key": "Key",
+        "kind": "Kind",
+        "origin": "Origin",
+        "actions": "Actions"
+      },
+      "kind": {
+        "simple": "Direct amount",
+        "priced": "Quantity × price"
+      },
+      "origin": {
+        "seeded": "Standard",
+        "user": "Custom"
+      },
+      "actions": {
+        "create": "New category",
+        "renamePrompt": "New label for this category",
+        "deleteConfirm": "Delete this category? This cannot be undone.",
+        "deleteSeedHint": "Standard categories cannot be deleted."
+      },
+      "form": {
+        "createTitle": "New category",
+        "key": "Key",
+        "keyPlaceholder": "e.g. lira, prpp",
+        "label": "Label",
+        "labelPlaceholder": "e.g. LIRA, PRPP",
+        "simpleOnlyNotice": "Priced categories (stocks, crypto) will be available in a future release.",
+        "create": "Create category"
+      },
+      "cash": "Cash",
+      "tfsa": "TFSA",
+      "rrsp": "RRSP",
+      "fund": "Mutual fund",
+      "other": "Other",
+      "stock": "Stock",
+      "crypto": "Crypto"
+    },
+    "errors": {
+      "currency_unsupported": "Only CAD is supported at the MVP.",
+      "category_seed_protected": "Standard categories cannot be deleted.",
+      "category_has_accounts": "Cannot delete a category with linked accounts. Move or archive linked accounts first.",
+      "category_not_found": "Category not found.",
+      "account_not_found": "Account not found.",
+      "name_required": "Name is required.",
+      "kind_invalid": "Invalid category kind."
+    }
   }
 }

src/i18n/locales/fr.json

@@ -1449,5 +1449,100 @@
         }
       }
     }
+  },
+  "balance": {
+    "accountsPage": {
+      "title": "Comptes du bilan",
+      "tabs": {
+        "accounts": "Comptes",
+        "categories": "Catégories"
+      },
+      "newAccount": "Nouveau compte",
+      "includeArchived": "Afficher les comptes archivés",
+      "empty": "Aucun compte pour l'instant. Cliquez sur « Nouveau compte » pour commencer."
+    },
+    "account": {
+      "fields": {
+        "name": "Nom",
+        "category": "Catégorie",
+        "symbol": "Symbole",
+        "currency": "Devise",
+        "status": "Statut",
+        "actions": "Actions"
+      },
+      "status": {
+        "active": "Actif",
+        "archived": "Archivé"
+      },
+      "actions": {
+        "archive": "Archiver",
+        "unarchive": "Restaurer"
+      },
+      "form": {
+        "createTitle": "Nouveau compte",
+        "editTitle": "Modifier le compte",
+        "category": "Catégorie",
+        "noCategory": "(aucune catégorie disponible)",
+        "name": "Nom du compte",
+        "nameRequired": "Le nom est obligatoire.",
+        "symbol": "Symbole",
+        "symbolPricedHint": "obligatoire pour cette catégorie cotée",
+        "symbolPlaceholderSimple": "Optionnel",
+        "symbolPlaceholderPriced": "ex. AAPL, BTC-USD",
+        "notes": "Notes",
+        "currencyMvpNotice": "Au MVP, tous les comptes sont en CAD. Le support multi-devises arrivera dans une version ultérieure.",
+        "save": "Enregistrer",
+        "create": "Créer le compte"
+      }
+    },
+    "category": {
+      "intro": "Les catégories seedées (CELI, REER, Encaisse, etc.) sont fournies par l'application. Vous pouvez en créer de nouvelles pour vos cas particuliers.",
+      "fields": {
+        "name": "Nom",
+        "key": "Clé",
+        "kind": "Type",
+        "origin": "Origine",
+        "actions": "Actions"
+      },
+      "kind": {
+        "simple": "Montant direct",
+        "priced": "Quantité × prix"
+      },
+      "origin": {
+        "seeded": "Standard",
+        "user": "Personnalisée"
+      },
+      "actions": {
+        "create": "Nouvelle catégorie",
+        "renamePrompt": "Nouveau libellé pour cette catégorie",
+        "deleteConfirm": "Supprimer cette catégorie ? Cette action est irréversible.",
+        "deleteSeedHint": "Les catégories standard ne peuvent pas être supprimées."
+      },
+      "form": {
+        "createTitle": "Nouvelle catégorie",
+        "key": "Clé",
+        "keyPlaceholder": "ex. ferr, rpdb",
+        "label": "Libellé",
+        "labelPlaceholder": "ex. FERR, RPDB",
+        "simpleOnlyNotice": "Les catégories cotées (actions, crypto) seront disponibles dans une prochaine version.",
+        "create": "Créer la catégorie"
+      },
+      "cash": "Encaisse",
+      "tfsa": "CELI",
+      "rrsp": "REER",
+      "fund": "Fonds commun",
+      "other": "Autre",
+      "stock": "Action",
+      "crypto": "Cryptomonnaie"
+    },
+    "errors": {
+      "currency_unsupported": "Seul le CAD est supporté au MVP.",
+      "category_seed_protected": "Les catégories standard ne peuvent pas être supprimées.",
+      "category_has_accounts": "Impossible de supprimer une catégorie avec des comptes liés. Déplacez ou archivez d'abord les comptes liés.",
+      "category_not_found": "Catégorie introuvable.",
+      "account_not_found": "Compte introuvable.",
+      "name_required": "Le nom est obligatoire.",
+      "kind_invalid": "Type de catégorie invalide."
+    }
   }
 }

src/pages/AccountsPage.tsx

@@ -0,0 +1,473 @@
+// AccountsPage — CRUD UI for balance accounts and balance categories.
+//
+// Issue #138 (Bilan #1a) ships the route `/balance/accounts` with two tabs:
+//   - Comptes  : full CRUD over balance_accounts (create/edit/archive)
+//   - Catégories : list of seeded + user-created categories. Users can add
+//                  simple-kind categories (the priced toggle lands in #140),
+//                  rename them, and delete the ones they created (the seeded
+//                  ones are protected at the service layer).
+//
+// The sidebar entry "Bilan" is intentionally NOT added here — per spec-plan
+// v2 it lands in Issue #141 (Bilan #3) when the `/balance` overview page
+// becomes navigable. Until then the route is reachable directly via URL.
+
+import { useMemo, useState } from "react";
+import { useTranslation } from "react-i18next";
+import { ArchiveRestore, Edit2, Plus, Trash2, Wallet } from "lucide-react";
+import type {
+  BalanceAccountWithCategory,
+  BalanceCategory,
+} from "../shared/types";
+import { useBalanceAccounts } from "../hooks/useBalanceAccounts";
+import AccountForm from "../components/balance/AccountForm";
+
+type Tab = "accounts" | "categories";
+
+export default function AccountsPage() {
+  const { t } = useTranslation();
+  const {
+    state,
+    setIncludeArchived,
+    addAccount,
+    editAccount,
+    archiveAccount,
+    unarchiveAccount,
+    addCategory,
+    editCategory,
+    removeCategory,
+  } = useBalanceAccounts();
+
+  const [activeTab, setActiveTab] = useState<Tab>("accounts");
+  const [showAccountForm, setShowAccountForm] = useState(false);
+  const [editingAccount, setEditingAccount] =
+    useState<BalanceAccountWithCategory | null>(null);
+
+  const [showCategoryForm, setShowCategoryForm] = useState(false);
+  const [newCategoryKey, setNewCategoryKey] = useState("");
+  const [newCategoryLabel, setNewCategoryLabel] = useState("");
+
+  const activeCategories = useMemo(
+    () => state.categories.filter((c) => c.is_active),
+    [state.categories]
+  );
+
+  const renderCategoryLabel = (cat: BalanceCategory) =>
+    t(cat.i18n_key, { defaultValue: cat.key });
+
+  const closeAccountForm = () => {
+    setShowAccountForm(false);
+    setEditingAccount(null);
+  };
+
+  const handleAccountSubmit = async (
+    payload:
+      | Parameters<typeof addAccount>[0]
+      | Parameters<typeof editAccount>[1]
+  ) => {
+    try {
+      if (editingAccount) {
+        await editAccount(editingAccount.id, payload as Parameters<typeof editAccount>[1]);
+      } else {
+        await addAccount(payload as Parameters<typeof addAccount>[0]);
+      }
+      closeAccountForm();
+    } catch {
+      // Error already surfaced via state.error
+    }
+  };
+
+  const handleCreateCategory = async () => {
+    const key = newCategoryKey.trim();
+    const label = newCategoryLabel.trim();
+    if (!key) return;
+    // For user-created categories we use the literal label as the i18n_key
+    // fallback — they don't ship in the locale bundle, so renderers default
+    // to this string. (The CategoryCombobox does the same for legacy v2 rows.)
+    const i18nKey = label || key;
+    try {
+      await addCategory({
+        key,
+        i18n_key: i18nKey,
+        kind: "simple",
+        sort_order: 100, // user-created categories sort after seeded ones
+      });
+      setNewCategoryKey("");
+      setNewCategoryLabel("");
+      setShowCategoryForm(false);
+    } catch {
+      // Error already surfaced via state.error
+    }
+  };
+
+  return (
+    <div className={state.isLoading ? "opacity-50 pointer-events-none" : ""}>
+      <div className="flex items-center gap-3 mb-6">
+        <Wallet size={24} className="text-[var(--primary)]" />
+        <h1 className="text-2xl font-bold">{t("balance.accountsPage.title")}</h1>
+      </div>
+
+      {state.error && (
+        <div className="mb-4 p-3 rounded-lg bg-[var(--negative)]/10 text-[var(--negative)] text-sm border border-[var(--negative)]/20">
+          {state.errorCode
+            ? t(`balance.errors.${state.errorCode}`, {
+                defaultValue: state.error,
+              })
+            : state.error}
+        </div>
+      )}
+
+      <div className="flex border-b border-[var(--border)] mb-6">
+        <button
+          type="button"
+          onClick={() => setActiveTab("accounts")}
+          className={`px-4 py-2 text-sm font-medium border-b-2 -mb-px ${
+            activeTab === "accounts"
+              ? "border-[var(--primary)] text-[var(--primary)]"
+              : "border-transparent text-[var(--muted-foreground)] hover:text-[var(--foreground)]"
+          }`}
+        >
+          {t("balance.accountsPage.tabs.accounts")}
+        </button>
+        <button
+          type="button"
+          onClick={() => setActiveTab("categories")}
+          className={`px-4 py-2 text-sm font-medium border-b-2 -mb-px ${
+            activeTab === "categories"
+              ? "border-[var(--primary)] text-[var(--primary)]"
+              : "border-transparent text-[var(--muted-foreground)] hover:text-[var(--foreground)]"
+          }`}
+        >
+          {t("balance.accountsPage.tabs.categories")}
+        </button>
+      </div>
+
+      {activeTab === "accounts" && (
+        <div>
+          <div className="flex flex-col sm:flex-row sm:items-center sm:justify-between gap-3 mb-4">
+            <label className="flex items-center gap-2 text-sm">
+              <input
+                type="checkbox"
+                checked={state.includeArchived}
+                onChange={(e) => setIncludeArchived(e.target.checked)}
+              />
+              {t("balance.accountsPage.includeArchived")}
+            </label>
+            <button
+              type="button"
+              onClick={() => {
+                setEditingAccount(null);
+                setShowAccountForm(true);
+              }}
+              disabled={activeCategories.length === 0}
+              className="flex items-center gap-2 px-4 py-2 rounded-lg bg-[var(--primary)] text-white text-sm font-medium hover:opacity-90 disabled:opacity-50"
+            >
+              <Plus size={16} />
+              {t("balance.accountsPage.newAccount")}
+            </button>
+          </div>
+
+          {showAccountForm ? (
+            <div className="bg-[var(--card)] rounded-xl border border-[var(--border)] p-4 mb-6">
+              <h2 className="text-lg font-semibold mb-4">
+                {editingAccount
+                  ? t("balance.account.form.editTitle")
+                  : t("balance.account.form.createTitle")}
+              </h2>
+              <AccountForm
+                initialAccount={editingAccount ?? null}
+                categories={activeCategories}
+                isSaving={state.isSaving}
+                onSubmit={handleAccountSubmit}
+                onCancel={closeAccountForm}
+              />
+            </div>
+          ) : null}
+
+          {state.accounts.length === 0 ? (
+            <div className="bg-[var(--card)] rounded-xl border border-[var(--border)] p-8 text-center text-[var(--muted-foreground)]">
+              {t("balance.accountsPage.empty")}
+            </div>
+          ) : (
+            <div className="bg-[var(--card)] rounded-xl border border-[var(--border)] overflow-hidden">
+              <table className="w-full text-sm">
+                <thead className="bg-[var(--muted)]">
+                  <tr>
+                    <th className="text-left px-4 py-2 font-medium">
+                      {t("balance.account.fields.name")}
+                    </th>
+                    <th className="text-left px-4 py-2 font-medium">
+                      {t("balance.account.fields.category")}
+                    </th>
+                    <th className="text-left px-4 py-2 font-medium">
+                      {t("balance.account.fields.symbol")}
+                    </th>
+                    <th className="text-left px-4 py-2 font-medium">
+                      {t("balance.account.fields.currency")}
+                    </th>
+                    <th className="text-left px-4 py-2 font-medium">
+                      {t("balance.account.fields.status")}
+                    </th>
+                    <th className="text-right px-4 py-2 font-medium">
+                      {t("balance.account.fields.actions")}
+                    </th>
+                  </tr>
+                </thead>
+                <tbody>
+                  {state.accounts.map((acc) => {
+                    const isArchived = !!acc.archived_at;
+                    return (
+                      <tr
+                        key={acc.id}
+                        className="border-t border-[var(--border)]"
+                      >
+                        <td className="px-4 py-2">
+                          <span className={isArchived ? "opacity-60" : ""}>
+                            {acc.name}
+                          </span>
+                        </td>
+                        <td className="px-4 py-2">
+                          {t(acc.category_i18n_key, {
+                            defaultValue: acc.category_key,
+                          })}
+                        </td>
+                        <td className="px-4 py-2 text-[var(--muted-foreground)]">
+                          {acc.symbol ?? "—"}
+                        </td>
+                        <td className="px-4 py-2 text-[var(--muted-foreground)]">
+                          {acc.currency}
+                        </td>
+                        <td className="px-4 py-2">
+                          {isArchived ? (
+                            <span className="text-xs px-2 py-0.5 rounded-full bg-[var(--muted)] text-[var(--muted-foreground)]">
+                              {t("balance.account.status.archived")}
+                            </span>
+                          ) : (
+                            <span className="text-xs px-2 py-0.5 rounded-full bg-[var(--positive)]/10 text-[var(--positive)]">
+                              {t("balance.account.status.active")}
+                            </span>
+                          )}
+                        </td>
+                        <td className="px-4 py-2 text-right">
+                          <div className="inline-flex items-center gap-1">
+                            <button
+                              type="button"
+                              onClick={() => {
+                                setEditingAccount(acc);
+                                setShowAccountForm(true);
+                              }}
+                              className="p-1.5 rounded hover:bg-[var(--muted)] text-[var(--muted-foreground)] hover:text-[var(--foreground)]"
+                              title={t("common.edit")}
+                            >
+                              <Edit2 size={14} />
+                            </button>
+                            {isArchived ? (
+                              <button
+                                type="button"
+                                onClick={() => unarchiveAccount(acc.id)}
+                                className="p-1.5 rounded hover:bg-[var(--muted)] text-[var(--muted-foreground)] hover:text-[var(--foreground)]"
+                                title={t("balance.account.actions.unarchive")}
+                              >
+                                <ArchiveRestore size={14} />
+                              </button>
+                            ) : (
+                              <button
+                                type="button"
+                                onClick={() => archiveAccount(acc.id)}
+                                className="p-1.5 rounded hover:bg-[var(--muted)] text-[var(--muted-foreground)] hover:text-[var(--negative)]"
+                                title={t("balance.account.actions.archive")}
+                              >
+                                <Trash2 size={14} />
+                              </button>
+                            )}
+                          </div>
+                        </td>
+                      </tr>
+                    );
+                  })}
+                </tbody>
+              </table>
+            </div>
+          )}
+        </div>
+      )}
+
+      {activeTab === "categories" && (
+        <div>
+          <div className="flex flex-col sm:flex-row sm:items-center sm:justify-between gap-3 mb-4">
+            <p className="text-sm text-[var(--muted-foreground)]">
+              {t("balance.category.intro")}
+            </p>
+            <button
+              type="button"
+              onClick={() => setShowCategoryForm((prev) => !prev)}
+              className="flex items-center gap-2 px-4 py-2 rounded-lg bg-[var(--primary)] text-white text-sm font-medium hover:opacity-90"
+            >
+              <Plus size={16} />
+              {t("balance.category.actions.create")}
+            </button>
+          </div>
+
+          {showCategoryForm && (
+            <div className="bg-[var(--card)] rounded-xl border border-[var(--border)] p-4 mb-6">
+              <h2 className="text-lg font-semibold mb-4">
+                {t("balance.category.form.createTitle")}
+              </h2>
+              <div className="grid grid-cols-1 sm:grid-cols-2 gap-4">
+                <div>
+                  <label
+                    className="block text-sm font-medium mb-1"
+                    htmlFor="category-key"
+                  >
+                    {t("balance.category.form.key")}
+                  </label>
+                  <input
+                    id="category-key"
+                    type="text"
+                    value={newCategoryKey}
+                    onChange={(e) => setNewCategoryKey(e.target.value)}
+                    className="w-full px-3 py-2 rounded-lg border border-[var(--border)] bg-[var(--card)] text-sm focus:outline-none focus:ring-1 focus:ring-[var(--primary)]"
+                    placeholder={t("balance.category.form.keyPlaceholder")}
+                    autoComplete="off"
+                  />
+                </div>
+                <div>
+                  <label
+                    className="block text-sm font-medium mb-1"
+                    htmlFor="category-label"
+                  >
+                    {t("balance.category.form.label")}
+                  </label>
+                  <input
+                    id="category-label"
+                    type="text"
+                    value={newCategoryLabel}
+                    onChange={(e) => setNewCategoryLabel(e.target.value)}
+                    className="w-full px-3 py-2 rounded-lg border border-[var(--border)] bg-[var(--card)] text-sm focus:outline-none focus:ring-1 focus:ring-[var(--primary)]"
+                    placeholder={t("balance.category.form.labelPlaceholder")}
+                    autoComplete="off"
+                  />
+                </div>
+              </div>
+              <p className="text-xs text-[var(--muted-foreground)] mt-3">
+                {t("balance.category.form.simpleOnlyNotice")}
+              </p>
+              <div className="flex justify-end gap-2 mt-4">
+                <button
+                  type="button"
+                  onClick={() => {
+                    setShowCategoryForm(false);
+                    setNewCategoryKey("");
+                    setNewCategoryLabel("");
+                  }}
+                  className="px-4 py-2 rounded-lg border border-[var(--border)] text-sm hover:bg-[var(--muted)]"
+                >
+                  {t("common.cancel")}
+                </button>
+                <button
+                  type="button"
+                  onClick={handleCreateCategory}
+                  disabled={state.isSaving || !newCategoryKey.trim()}
+                  className="px-4 py-2 rounded-lg bg-[var(--primary)] text-white text-sm font-medium hover:opacity-90 disabled:opacity-50"
+                >
+                  {t("balance.category.form.create")}
+                </button>
+              </div>
+            </div>
+          )}
+
+          <div className="bg-[var(--card)] rounded-xl border border-[var(--border)] overflow-hidden">
+            <table className="w-full text-sm">
+              <thead className="bg-[var(--muted)]">
+                <tr>
+                  <th className="text-left px-4 py-2 font-medium">
+                    {t("balance.category.fields.name")}
+                  </th>
+                  <th className="text-left px-4 py-2 font-medium">
+                    {t("balance.category.fields.key")}
+                  </th>
+                  <th className="text-left px-4 py-2 font-medium">
+                    {t("balance.category.fields.kind")}
+                  </th>
+                  <th className="text-left px-4 py-2 font-medium">
+                    {t("balance.category.fields.origin")}
+                  </th>
+                  <th className="text-right px-4 py-2 font-medium">
+                    {t("balance.category.fields.actions")}
+                  </th>
+                </tr>
+              </thead>
+              <tbody>
+                {state.categories.map((cat) => (
+                  <tr key={cat.id} className="border-t border-[var(--border)]">
+                    <td className="px-4 py-2">{renderCategoryLabel(cat)}</td>
+                    <td className="px-4 py-2 text-[var(--muted-foreground)]">
+                      <code className="text-xs">{cat.key}</code>
+                    </td>
+                    <td className="px-4 py-2">
+                      <span className="text-xs px-2 py-0.5 rounded-full bg-[var(--muted)]">
+                        {t(`balance.category.kind.${cat.kind}`)}
+                      </span>
+                    </td>
+                    <td className="px-4 py-2">
+                      {cat.is_seed ? (
+                        <span className="text-xs text-[var(--muted-foreground)]">
+                          {t("balance.category.origin.seeded")}
+                        </span>
+                      ) : (
+                        <span className="text-xs text-[var(--muted-foreground)]">
+                          {t("balance.category.origin.user")}
+                        </span>
+                      )}
+                    </td>
+                    <td className="px-4 py-2 text-right">
+                      <div className="inline-flex items-center gap-1">
+                        <button
+                          type="button"
+                          onClick={() => {
+                            const next = window.prompt(
+                              t("balance.category.actions.renamePrompt"),
+                              renderCategoryLabel(cat)
+                            );
+                            if (next && next.trim()) {
+                              editCategory(cat.id, { i18n_key: next.trim() });
+                            }
+                          }}
+                          className="p-1.5 rounded hover:bg-[var(--muted)] text-[var(--muted-foreground)] hover:text-[var(--foreground)]"
+                          title={t("common.edit")}
+                        >
+                          <Edit2 size={14} />
+                        </button>
+                        <button
+                          type="button"
+                          onClick={() => {
+                            if (cat.is_seed) return;
+                            if (
+                              window.confirm(
+                                t("balance.category.actions.deleteConfirm")
+                              )
+                            ) {
+                              removeCategory(cat.id);
+                            }
+                          }}
+                          disabled={cat.is_seed}
+                          title={
+                            cat.is_seed
+                              ? t("balance.category.actions.deleteSeedHint")
+                              : t("common.delete")
+                          }
+                          className="p-1.5 rounded hover:bg-[var(--muted)] text-[var(--muted-foreground)] hover:text-[var(--negative)] disabled:opacity-30 disabled:cursor-not-allowed"
+                        >
+                          <Trash2 size={14} />
+                        </button>
+                      </div>
+                    </td>
+                  </tr>
+                ))}
+              </tbody>
+            </table>
+          </div>
+        </div>
+      )}
+    </div>
+  );
+}

src/services/balance.service.test.ts

@@ -0,0 +1,316 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+
+vi.mock("./db", () => ({
+  getDb: vi.fn(),
+}));
+
+import { getDb } from "./db";
+import {
+  listBalanceCategories,
+  createBalanceCategory,
+  updateBalanceCategory,
+  deleteBalanceCategory,
+  listBalanceAccounts,
+  createBalanceAccount,
+  updateBalanceAccount,
+  archiveBalanceAccount,
+  unarchiveBalanceAccount,
+  BalanceServiceError,
+} from "./balance.service";
+
+const mockSelect = vi.fn();
+const mockExecute = vi.fn();
+const mockDb = { select: mockSelect, execute: mockExecute };
+
+beforeEach(() => {
+  vi.mocked(getDb).mockResolvedValue(mockDb as never);
+  mockSelect.mockReset();
+  mockExecute.mockReset();
+});
+
+// -----------------------------------------------------------------------------
+// Categories
+// -----------------------------------------------------------------------------
+
+describe("listBalanceCategories", () => {
+  it("orders by sort_order then key", async () => {
+    mockSelect.mockResolvedValueOnce([]);
+    await listBalanceCategories();
+    const sql = mockSelect.mock.calls[0][0] as string;
+    expect(sql).toContain("FROM balance_categories");
+    expect(sql).toContain("ORDER BY sort_order, key");
+  });
+});
+
+describe("createBalanceCategory", () => {
+  it("rejects an empty key", async () => {
+    await expect(
+      createBalanceCategory({ key: "  ", i18n_key: "x", kind: "simple" })
+    ).rejects.toBeInstanceOf(BalanceServiceError);
+    expect(mockExecute).not.toHaveBeenCalled();
+  });
+
+  it("rejects an invalid kind", async () => {
+    await expect(
+      createBalanceCategory({
+        key: "custom",
+        i18n_key: "balance.category.custom",
+        // @ts-expect-error testing runtime guard
+        kind: "weird",
+      })
+    ).rejects.toBeInstanceOf(BalanceServiceError);
+    expect(mockExecute).not.toHaveBeenCalled();
+  });
+
+  it("inserts with is_seed = 0 and returns lastInsertId", async () => {
+    mockExecute.mockResolvedValueOnce({ lastInsertId: 42, rowsAffected: 1 });
+    const id = await createBalanceCategory({
+      key: "ferr",
+      i18n_key: "balance.category.ferr",
+      kind: "simple",
+      sort_order: 35,
+    });
+    expect(id).toBe(42);
+    const sql = mockExecute.mock.calls[0][0] as string;
+    const params = mockExecute.mock.calls[0][1] as unknown[];
+    expect(sql).toContain("INSERT INTO balance_categories");
+    expect(sql).toContain("is_seed");
+    expect(sql).toMatch(/0\)$/); // is_seed hardcoded to 0
+    expect(params).toEqual(["ferr", "balance.category.ferr", "simple", 35]);
+  });
+});
+
+describe("deleteBalanceCategory", () => {
+  it("refuses to delete a seeded category", async () => {
+    mockSelect.mockResolvedValueOnce([
+      {
+        id: 1,
+        key: "cash",
+        i18n_key: "balance.category.cash",
+        kind: "simple",
+        sort_order: 10,
+        is_active: 1,
+        is_seed: 1,
+      },
+    ]);
+    await expect(deleteBalanceCategory(1)).rejects.toMatchObject({
+      code: "category_seed_protected",
+    });
+    expect(mockExecute).not.toHaveBeenCalled();
+  });
+
+  it("refuses to delete a category with linked accounts", async () => {
+    // 1st select = getBalanceCategory; 2nd select = COUNT(*) accounts linked
+    mockSelect
+      .mockResolvedValueOnce([
+        {
+          id: 8,
+          key: "ferr",
+          i18n_key: "balance.category.ferr",
+          kind: "simple",
+          sort_order: 35,
+          is_active: 1,
+          is_seed: 0,
+        },
+      ])
+      .mockResolvedValueOnce([{ count: 2 }]);
+    await expect(deleteBalanceCategory(8)).rejects.toMatchObject({
+      code: "category_has_accounts",
+    });
+    expect(mockExecute).not.toHaveBeenCalled();
+  });
+
+  it("deletes a user-created category with no linked accounts", async () => {
+    mockSelect
+      .mockResolvedValueOnce([
+        {
+          id: 8,
+          key: "ferr",
+          i18n_key: "balance.category.ferr",
+          kind: "simple",
+          sort_order: 35,
+          is_active: 1,
+          is_seed: 0,
+        },
+      ])
+      .mockResolvedValueOnce([{ count: 0 }]);
+    mockExecute.mockResolvedValueOnce({ rowsAffected: 1 });
+    await deleteBalanceCategory(8);
+    expect(mockExecute).toHaveBeenCalledWith(
+      "DELETE FROM balance_categories WHERE id = $1",
+      [8]
+    );
+  });
+});
+
+describe("updateBalanceCategory", () => {
+  it("renames a seeded category (allowed)", async () => {
+    mockSelect.mockResolvedValueOnce([
+      {
+        id: 1,
+        key: "cash",
+        i18n_key: "balance.category.cash",
+        kind: "simple",
+        sort_order: 10,
+        is_active: 1,
+        is_seed: 1,
+      },
+    ]);
+    mockExecute.mockResolvedValueOnce({ rowsAffected: 1 });
+    await updateBalanceCategory(1, { i18n_key: "balance.category.cash_renamed" });
+    const params = mockExecute.mock.calls[0][1] as unknown[];
+    expect(params[0]).toBe("balance.category.cash_renamed");
+  });
+
+  it("rejects update on missing category", async () => {
+    mockSelect.mockResolvedValueOnce([]);
+    await expect(updateBalanceCategory(999, { sort_order: 5 })).rejects.toMatchObject({
+      code: "category_not_found",
+    });
+  });
+});
+
+// -----------------------------------------------------------------------------
+// Accounts
+// -----------------------------------------------------------------------------
+
+describe("listBalanceAccounts", () => {
+  it("excludes archived accounts by default", async () => {
+    mockSelect.mockResolvedValueOnce([]);
+    await listBalanceAccounts();
+    const sql = mockSelect.mock.calls[0][0] as string;
+    expect(sql).toContain("a.is_active = 1");
+    expect(sql).toContain("a.archived_at IS NULL");
+  });
+
+  it("includes archived accounts when requested", async () => {
+    mockSelect.mockResolvedValueOnce([]);
+    await listBalanceAccounts({ includeArchived: true });
+    const sql = mockSelect.mock.calls[0][0] as string;
+    expect(sql).not.toContain("archived_at IS NULL");
+  });
+});
+
+describe("createBalanceAccount", () => {
+  it("rejects empty name", async () => {
+    await expect(
+      createBalanceAccount({ balance_category_id: 1, name: "  " })
+    ).rejects.toMatchObject({ code: "name_required" });
+  });
+
+  it("rejects non-CAD currency at the MVP", async () => {
+    await expect(
+      createBalanceAccount({
+        balance_category_id: 1,
+        name: "USD account",
+        currency: "USD",
+      })
+    ).rejects.toMatchObject({ code: "currency_unsupported" });
+    expect(mockExecute).not.toHaveBeenCalled();
+  });
+
+  it("rejects when the category does not exist", async () => {
+    mockSelect.mockResolvedValueOnce([]); // getBalanceCategory returns null
+    await expect(
+      createBalanceAccount({ balance_category_id: 999, name: "Mystery" })
+    ).rejects.toMatchObject({ code: "category_not_found" });
+  });
+
+  it("inserts with default CAD currency", async () => {
+    mockSelect.mockResolvedValueOnce([
+      {
+        id: 1,
+        key: "cash",
+        i18n_key: "balance.category.cash",
+        kind: "simple",
+        sort_order: 10,
+        is_active: 1,
+        is_seed: 1,
+      },
+    ]);
+    mockExecute.mockResolvedValueOnce({ lastInsertId: 7, rowsAffected: 1 });
+    const id = await createBalanceAccount({
+      balance_category_id: 1,
+      name: "Encaisse Wealthsimple",
+    });
+    expect(id).toBe(7);
+    const params = mockExecute.mock.calls[0][1] as unknown[];
+    expect(params).toEqual([1, "Encaisse Wealthsimple", null, "CAD", null]);
+  });
+});
+
+describe("updateBalanceAccount", () => {
+  it("rejects when account does not exist", async () => {
+    mockSelect.mockResolvedValueOnce([]);
+    await expect(updateBalanceAccount(42, { name: "x" })).rejects.toMatchObject({
+      code: "account_not_found",
+    });
+  });
+
+  it("normalizes empty symbol to null", async () => {
+    mockSelect.mockResolvedValueOnce([
+      {
+        id: 7,
+        balance_category_id: 1,
+        name: "Encaisse",
+        symbol: "OLD",
+        currency: "CAD",
+        notes: null,
+        is_active: 1,
+        archived_at: null,
+        created_at: "",
+        updated_at: "",
+      },
+    ]);
+    mockExecute.mockResolvedValueOnce({ rowsAffected: 1 });
+    await updateBalanceAccount(7, { symbol: "  " });
+    const params = mockExecute.mock.calls[0][1] as unknown[];
+    expect(params[2]).toBeNull(); // symbol
+  });
+});
+
+describe("archiveBalanceAccount / unarchiveBalanceAccount", () => {
+  it("archives an existing account", async () => {
+    mockSelect.mockResolvedValueOnce([
+      {
+        id: 7,
+        balance_category_id: 1,
+        name: "Encaisse",
+        symbol: null,
+        currency: "CAD",
+        notes: null,
+        is_active: 1,
+        archived_at: null,
+        created_at: "",
+        updated_at: "",
+      },
+    ]);
+    mockExecute.mockResolvedValueOnce({ rowsAffected: 1 });
+    await archiveBalanceAccount(7);
+    const sql = mockExecute.mock.calls[0][0] as string;
+    expect(sql).toContain("archived_at = CURRENT_TIMESTAMP");
+    expect(sql).toContain("is_active = 0");
+  });
+
+  it("unarchives an existing account", async () => {
+    mockSelect.mockResolvedValueOnce([
+      {
+        id: 7,
+        balance_category_id: 1,
+        name: "Encaisse",
+        symbol: null,
+        currency: "CAD",
+        notes: null,
+        is_active: 0,
+        archived_at: "2026-04-25 10:00:00",
+        created_at: "",
+        updated_at: "",
+      },
+    ]);
+    mockExecute.mockResolvedValueOnce({ rowsAffected: 1 });
+    await unarchiveBalanceAccount(7);
+    const sql = mockExecute.mock.calls[0][0] as string;
+    expect(sql).toContain("archived_at = NULL");
+    expect(sql).toContain("is_active = 1");
+  });
+});

src/services/balance.service.ts

@@ -0,0 +1,360 @@
+// balance.service.ts — domain service for the Bilan (balance sheet) feature.
+//
+// Scope at Issue #138 (Bilan #1a): CRUD for `balance_categories` and
+// `balance_accounts` only. Snapshots, snapshot lines, transfers and price
+// fetching ship in subsequent issues (#1b / #2 / #4 / #5).
+//
+// CRUD goes through `getDb()` + tauri-plugin-sql directly — the project
+// convention for database operations. Tauri commands are reserved for
+// filesystem / OAuth / license / profile work and the future Modified Dietz
+// + price-fetch work in Issue #142.
+
+import { getDb } from "./db";
+import type {
+  BalanceAccount,
+  BalanceAccountWithCategory,
+  BalanceCategory,
+  BalanceCategoryKind,
+} from "../shared/types";
+import { BALANCE_CURRENCY_CAD } from "../shared/types";
+
+// -----------------------------------------------------------------------------
+// Errors — typed so the UI can show distinct i18n messages.
+// -----------------------------------------------------------------------------
+
+export type BalanceErrorCode =
+  | "currency_unsupported"
+  | "category_seed_protected"
+  | "category_has_accounts"
+  | "category_not_found"
+  | "account_not_found"
+  | "name_required"
+  | "kind_invalid";
+
+export class BalanceServiceError extends Error {
+  readonly code: BalanceErrorCode;
+  constructor(code: BalanceErrorCode, message: string) {
+    super(message);
+    this.name = "BalanceServiceError";
+    this.code = code;
+  }
+}
+
+// -----------------------------------------------------------------------------
+// Categories
+// -----------------------------------------------------------------------------
+
+export async function listBalanceCategories(): Promise<BalanceCategory[]> {
+  const db = await getDb();
+  return db.select<BalanceCategory[]>(
+    `SELECT id, key, i18n_key, kind, sort_order, is_active, is_seed
+     FROM balance_categories
+     ORDER BY sort_order, key`
+  );
+}
+
+export async function getBalanceCategory(
+  id: number
+): Promise<BalanceCategory | null> {
+  const db = await getDb();
+  const rows = await db.select<BalanceCategory[]>(
+    `SELECT id, key, i18n_key, kind, sort_order, is_active, is_seed
+     FROM balance_categories
+     WHERE id = $1`,
+    [id]
+  );
+  return rows[0] ?? null;
+}
+
+export interface CreateBalanceCategoryInput {
+  key: string;
+  i18n_key: string;
+  kind: BalanceCategoryKind;
+  sort_order?: number;
+}
+
+/**
+ * Create a user-defined balance category. The seed categories are created by
+ * Migration v9 — never call this for seeded keys (UNIQUE will reject the
+ * insert anyway).
+ *
+ * Note (Issue #138): the AccountsPage UI restricts user-created categories to
+ * `kind = 'simple'`. The service still accepts both because the priced UI
+ * lands in Issue #140.
+ */
+export async function createBalanceCategory(
+  input: CreateBalanceCategoryInput
+): Promise<number> {
+  if (!input.key || input.key.trim().length === 0) {
+    throw new BalanceServiceError("name_required", "Category key is required");
+  }
+  if (input.kind !== "simple" && input.kind !== "priced") {
+    throw new BalanceServiceError("kind_invalid", "Invalid category kind");
+  }
+  const db = await getDb();
+  const result = await db.execute(
+    `INSERT INTO balance_categories (key, i18n_key, kind, sort_order, is_active, is_seed)
+     VALUES ($1, $2, $3, $4, 1, 0)`,
+    [
+      input.key.trim(),
+      input.i18n_key.trim(),
+      input.kind,
+      input.sort_order ?? 0,
+    ]
+  );
+  return result.lastInsertId as number;
+}
+
+export interface UpdateBalanceCategoryInput {
+  i18n_key?: string;
+  sort_order?: number;
+  is_active?: boolean;
+}
+
+/**
+ * Rename / re-order / toggle active state of a category. Seeded categories
+ * are renamable. Changing `kind` is intentionally not supported (would
+ * invalidate existing snapshot lines).
+ */
+export async function updateBalanceCategory(
+  id: number,
+  input: UpdateBalanceCategoryInput
+): Promise<void> {
+  const existing = await getBalanceCategory(id);
+  if (!existing) {
+    throw new BalanceServiceError(
+      "category_not_found",
+      `Category ${id} not found`
+    );
+  }
+  const db = await getDb();
+  const i18n = input.i18n_key !== undefined ? input.i18n_key : existing.i18n_key;
+  const sortOrder =
+    input.sort_order !== undefined ? input.sort_order : existing.sort_order;
+  const isActive =
+    input.is_active !== undefined ? (input.is_active ? 1 : 0) : existing.is_active ? 1 : 0;
+  await db.execute(
+    `UPDATE balance_categories
+       SET i18n_key = $1, sort_order = $2, is_active = $3
+     WHERE id = $4`,
+    [i18n, sortOrder, isActive, id]
+  );
+}
+
+/**
+ * Delete a user-created category. Refuses to delete:
+ *   - seeded categories (`is_seed = 1`) — UI must disable the button;
+ *   - categories with linked accounts — FK RESTRICT would also reject, but
+ *     we pre-check to surface a clean i18n message.
+ */
+export async function deleteBalanceCategory(id: number): Promise<void> {
+  const existing = await getBalanceCategory(id);
+  if (!existing) {
+    throw new BalanceServiceError(
+      "category_not_found",
+      `Category ${id} not found`
+    );
+  }
+  if (existing.is_seed) {
+    throw new BalanceServiceError(
+      "category_seed_protected",
+      "Seeded categories cannot be deleted"
+    );
+  }
+  const db = await getDb();
+  const linked = await db.select<Array<{ count: number }>>(
+    `SELECT COUNT(*) AS count FROM balance_accounts WHERE balance_category_id = $1`,
+    [id]
+  );
+  if ((linked[0]?.count ?? 0) > 0) {
+    throw new BalanceServiceError(
+      "category_has_accounts",
+      "Cannot delete a category with linked accounts"
+    );
+  }
+  await db.execute("DELETE FROM balance_categories WHERE id = $1", [id]);
+}
+
+// -----------------------------------------------------------------------------
+// Accounts
+// -----------------------------------------------------------------------------
+
+export async function listBalanceAccounts(options?: {
+  includeArchived?: boolean;
+}): Promise<BalanceAccountWithCategory[]> {
+  const includeArchived = options?.includeArchived ?? false;
+  const db = await getDb();
+  const where = includeArchived
+    ? ""
+    : "WHERE a.is_active = 1 AND a.archived_at IS NULL";
+  return db.select<BalanceAccountWithCategory[]>(
+    `SELECT a.id, a.balance_category_id, a.name, a.symbol, a.currency,
+            a.notes, a.is_active, a.archived_at, a.created_at, a.updated_at,
+            c.key AS category_key, c.i18n_key AS category_i18n_key, c.kind AS category_kind
+     FROM balance_accounts a
+     INNER JOIN balance_categories c ON c.id = a.balance_category_id
+     ${where}
+     ORDER BY c.sort_order, a.name`
+  );
+}
+
+export async function getBalanceAccount(
+  id: number
+): Promise<BalanceAccount | null> {
+  const db = await getDb();
+  const rows = await db.select<BalanceAccount[]>(
+    `SELECT id, balance_category_id, name, symbol, currency, notes,
+            is_active, archived_at, created_at, updated_at
+     FROM balance_accounts
+     WHERE id = $1`,
+    [id]
+  );
+  return rows[0] ?? null;
+}
+
+export interface CreateBalanceAccountInput {
+  balance_category_id: number;
+  name: string;
+  symbol?: string | null;
+  /** Defaults to 'CAD'. MVP rejects any other value. */
+  currency?: string;
+  notes?: string | null;
+}
+
+/**
+ * Create an account. Currency must be 'CAD' at the MVP — the SQL CHECK
+ * would reject anything else, but we pre-check to surface a clean i18n
+ * message instead of a raw SQL error.
+ */
+export async function createBalanceAccount(
+  input: CreateBalanceAccountInput
+): Promise<number> {
+  if (!input.name || input.name.trim().length === 0) {
+    throw new BalanceServiceError("name_required", "Account name is required");
+  }
+  const currency = input.currency ?? BALANCE_CURRENCY_CAD;
+  if (currency !== BALANCE_CURRENCY_CAD) {
+    throw new BalanceServiceError(
+      "currency_unsupported",
+      "Only CAD is supported at the MVP"
+    );
+  }
+  const cat = await getBalanceCategory(input.balance_category_id);
+  if (!cat) {
+    throw new BalanceServiceError(
+      "category_not_found",
+      "Linked balance category not found"
+    );
+  }
+  const db = await getDb();
+  const result = await db.execute(
+    `INSERT INTO balance_accounts (balance_category_id, name, symbol, currency, notes, is_active)
+     VALUES ($1, $2, $3, $4, $5, 1)`,
+    [
+      input.balance_category_id,
+      input.name.trim(),
+      input.symbol ? input.symbol.trim() : null,
+      currency,
+      input.notes ? input.notes.trim() : null,
+    ]
+  );
+  return result.lastInsertId as number;
+}
+
+export interface UpdateBalanceAccountInput {
+  balance_category_id?: number;
+  name?: string;
+  symbol?: string | null;
+  notes?: string | null;
+  is_active?: boolean;
+}
+
+export async function updateBalanceAccount(
+  id: number,
+  input: UpdateBalanceAccountInput
+): Promise<void> {
+  const existing = await getBalanceAccount(id);
+  if (!existing) {
+    throw new BalanceServiceError(
+      "account_not_found",
+      `Account ${id} not found`
+    );
+  }
+  const name = input.name !== undefined ? input.name.trim() : existing.name;
+  if (!name) {
+    throw new BalanceServiceError("name_required", "Account name is required");
+  }
+  const categoryId =
+    input.balance_category_id !== undefined
+      ? input.balance_category_id
+      : existing.balance_category_id;
+  const symbol =
+    input.symbol !== undefined
+      ? input.symbol === null
+        ? null
+        : input.symbol.trim() || null
+      : existing.symbol;
+  const notes =
+    input.notes !== undefined
+      ? input.notes === null
+        ? null
+        : input.notes.trim() || null
+      : existing.notes;
+  const isActive =
+    input.is_active !== undefined
+      ? input.is_active
+        ? 1
+        : 0
+      : existing.is_active
+        ? 1
+        : 0;
+  const db = await getDb();
+  await db.execute(
+    `UPDATE balance_accounts
+       SET balance_category_id = $1, name = $2, symbol = $3, notes = $4,
+           is_active = $5, updated_at = CURRENT_TIMESTAMP
+     WHERE id = $6`,
+    [categoryId, name, symbol, notes, isActive, id]
+  );
+}
+
+/**
+ * Soft-delete an account: stamp `archived_at` and set `is_active = 0`.
+ * Archived accounts are hidden from new snapshots but kept in the historic
+ * snapshot lines (which is why we never hard-delete here).
+ */
+export async function archiveBalanceAccount(id: number): Promise<void> {
+  const existing = await getBalanceAccount(id);
+  if (!existing) {
+    throw new BalanceServiceError(
+      "account_not_found",
+      `Account ${id} not found`
+    );
+  }
+  const db = await getDb();
+  await db.execute(
+    `UPDATE balance_accounts
+       SET archived_at = CURRENT_TIMESTAMP, is_active = 0,
+           updated_at = CURRENT_TIMESTAMP
+     WHERE id = $1`,
+    [id]
+  );
+}
+
+export async function unarchiveBalanceAccount(id: number): Promise<void> {
+  const existing = await getBalanceAccount(id);
+  if (!existing) {
+    throw new BalanceServiceError(
+      "account_not_found",
+      `Account ${id} not found`
+    );
+  }
+  const db = await getDb();
+  await db.execute(
+    `UPDATE balance_accounts
+       SET archived_at = NULL, is_active = 1,
+           updated_at = CURRENT_TIMESTAMP
+     WHERE id = $1`,
+    [id]
+  );
+}

src/shared/types/index.ts

@@ -555,3 +555,49 @@ export interface TransactionPageResult {
   incomeTotal: number;
   expenseTotal: number;
 }
+
+// --- Balance (Bilan) types ---
+// Backed by migration v9 (see src-tauri/src/database/balance_schema.sql).
+// MVP scope (Issue #138 / #1a): categories + accounts CRUD only. Snapshots,
+// snapshot lines and transfers ship in subsequent issues (#1b / #2 / #4).
+
+export type BalanceCategoryKind = "simple" | "priced";
+
+export const BALANCE_CURRENCY_CAD = "CAD";
+
+export interface BalanceCategory {
+  id: number;
+  /** Stable lookup key (e.g. 'cash', 'tfsa', 'stock'). UNIQUE NOT NULL. */
+  key: string;
+  /** Translation key into i18n locales (e.g. 'balance.category.cash'). */
+  i18n_key: string;
+  /** simple = direct value entry; priced = quantity x unit_price. */
+  kind: BalanceCategoryKind;
+  sort_order: number;
+  is_active: boolean;
+  /** True when seeded by Migration v9 — cannot be deleted, can be renamed. */
+  is_seed: boolean;
+}
+
+export interface BalanceAccount {
+  id: number;
+  balance_category_id: number;
+  name: string;
+  /** Symbol (e.g. 'AAPL', 'BTC-USD'); NULL for simple-kind accounts. */
+  symbol: string | null;
+  /** ISO 4217. MVP: hardcoded 'CAD' (CHECK enforced server-side). */
+  currency: string;
+  notes: string | null;
+  is_active: boolean;
+  /** Soft-delete timestamp; archived accounts hide from new snapshots. */
+  archived_at: string | null;
+  created_at: string;
+  updated_at: string;
+}
+
+/** Joined view used by AccountsPage tables. */
+export interface BalanceAccountWithCategory extends BalanceAccount {
+  category_key: string;
+  category_i18n_key: string;
+  category_kind: BalanceCategoryKind;
+}