diff --git a/sql/registry.sql b/sql/registry.sql
index 6e39a39..1767682 100644
--- a/sql/registry.sql
+++ b/sql/registry.sql
@@ -8,7 +8,7 @@ CREATE TABLE shards (
     db_name VARCHAR(50) NOT NULL,
     host_address VARCHAR(255) NOT NULL,
     port INT NOT NULL DEFAULT 53096
-);
+) ENGINE=InnoDB;
 
 CREATE TABLE user_shard_map (
     user_id BINARY(16) PRIMARY KEY,
@@ -19,45 +19,38 @@ CREATE TABLE user_shard_map (
     is_active TINYINT(1) NOT NULL DEFAULT 1,
     created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     FOREIGN KEY (shard_id) REFERENCES shards(shard_id)
-);
+) ENGINE=InnoDB;
 
 CREATE TABLE cost_group_statuses (
     status_id TINYINT PRIMARY KEY,
     name VARCHAR(20) UNIQUE NOT NULL
-);
+) ENGINE=InnoDB;
 
 CREATE TABLE cost_groups (
     group_id BINARY(16) PRIMARY KEY,
     name VARCHAR(100) NOT NULL,
     created_by BINARY(16),
-    status_id TINYINT NOT NULL DEFAULT '1',
+    status_id TINYINT NOT NULL DEFAULT 1,
     created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     FOREIGN KEY (created_by) REFERENCES user_shard_map(user_id),
     FOREIGN KEY (status_id) REFERENCES cost_group_statuses(status_id)
-);
+) ENGINE=InnoDB;
 
 CREATE TABLE group_roles (
     role_id TINYINT PRIMARY KEY,
     name VARCHAR(20) UNIQUE NOT NULL
-);
+) ENGINE=InnoDB;
 
 CREATE TABLE group_members (
     group_id BINARY(16),
     user_id BINARY(16),
-    role_id TINYINT DEFAULT '3',
+    role_id TINYINT DEFAULT 3,
     joined_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
     PRIMARY KEY (group_id, user_id),
     FOREIGN KEY (group_id) REFERENCES cost_groups(group_id),
-    FOREIGN KEY (role_id) REFERENCES group_roles(role_id),
-    FOREIGN KEY (user_id) REFERENCES user_shard_map(user_id)
-);
+    FOREIGN KEY (user_id) REFERENCES user_shard_map(user_id),
+    FOREIGN KEY (role_id) REFERENCES group_roles(role_id)
+) ENGINE=InnoDB;
 
-INSERT INTO cost_group_statuses (status_id, name) VALUES
-(1, 'active'),
-(2, 'settled'),
-(3, 'archived');
-
-INSERT INTO group_roles (role_id, name) VALUES
-(1, 'owner'),
-(2, 'editor'),
-(3, 'participant');
+INSERT INTO cost_group_statuses (status_id, name) VALUES (1, 'active'), (2, 'settled'), (3, 'archived');
+INSERT INTO group_roles (role_id, name) VALUES (1, 'owner'), (2, 'editor'), (3, 'participant');
diff --git a/sql/shard.sql b/sql/shard.sql
index b3f17bf..a14e2e8 100644
--- a/sql/shard.sql
+++ b/sql/shard.sql
@@ -5,88 +5,95 @@ USE argent_shard_01;
 CREATE TABLE ledger_statuses (
     status_id TINYINT PRIMARY KEY,
     name VARCHAR(20) UNIQUE NOT NULL
-);
+) ENGINE=InnoDB;
+
+CREATE TABLE ledger_entry_types (
+    type_id TINYINT PRIMARY KEY,
+    name VARCHAR(20) UNIQUE NOT NULL
+) ENGINE=InnoDB;
 
 CREATE TABLE ledger (
     entry_id BINARY(16) NOT NULL,
     batch_id BINARY(16) NOT NULL,
     user_id BINARY(16) NOT NULL,
     group_id BINARY(16) DEFAULT NULL,
-    category_id INT,
     amount DECIMAL(15, 2) NOT NULL,
     currency_code CHAR(3) NOT NULL,
     description VARCHAR(255),
-    status_id TINYINT DEFAULT '1',
+    status_id TINYINT DEFAULT 1,
+    type_id TINYINT NOT NULL,
     created_at DATETIME NOT NULL,
-    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
-
     PRIMARY KEY (user_id, entry_id),
     FOREIGN KEY (status_id) REFERENCES ledger_statuses(status_id),
+    FOREIGN KEY (type_id) REFERENCES ledger_entry_types(type_id),
     INDEX (batch_id),
     INDEX (group_id),
     INDEX (status_id)
-);
+) ENGINE=InnoDB;
 
 CREATE TABLE user_balances (
     user_id BINARY(16) NOT NULL,
     currency_code CHAR(3) NOT NULL,
-    total_confirmed DECIMAL(15, 2) DEFAULT 0.00,
-    total_pending DECIMAL(15, 2) DEFAULT 0.00,
+    total_proposed DECIMAL(15, 2) DEFAULT 0.00,
+    total_ratified DECIMAL(15, 2) DEFAULT 0.00,
+    total_disputed DECIMAL(15, 2) DEFAULT 0.00,
+    total_settled  DECIMAL(15, 2) DEFAULT 0.00,
+    total_spent    DECIMAL(15, 2) DEFAULT 0.00,
     PRIMARY KEY (user_id, currency_code)
-);
+) ENGINE=InnoDB;
 
-INSERT INTO ledger_statuses (status_id, name) VALUES
-(1, 'proposed'),
-(2, 'ratified'),
-(3, 'disputed'),
-(4, 'settled');
+CREATE TABLE group_user_balances (
+    group_id BINARY(16) NOT NULL,
+    user_id BINARY(16) NOT NULL,
+    currency_code CHAR(3) NOT NULL,
+    net_balance DECIMAL(15, 2) DEFAULT 0.00,
+    total_contributed DECIMAL(15, 2) DEFAULT 0.00,
+    PRIMARY KEY (group_id, user_id, currency_code),
+    INDEX (user_id)
+) ENGINE=InnoDB;
+
+INSERT INTO ledger_statuses (status_id, name) VALUES (1, 'proposed'), (2, 'ratified'), (3, 'disputed'), (4, 'settled');
+INSERT INTO ledger_entry_types (type_id, name) VALUES (1, 'expense'), (2, 'settlement');
 
 DELIMITER //
-CREATE TRIGGER after_ledger_insert
-AFTER INSERT ON ledger
-FOR EACH ROW
+CREATE PROCEDURE sync_all_balances(
+    IN p_uid BINARY(16),
+    IN p_gid BINARY(16),
+    IN p_curr CHAR(3),
+    IN p_amt DECIMAL(15,2),
+    IN p_status TINYINT,
+    IN p_type TINYINT,
+    IN p_mod INT
+)
 BEGIN
-    IF NEW.status_id = 1 THEN
-        UPDATE user_balances
-        SET total_pending = total_pending + NEW.amount
-        WHERE user_id = NEW.user_id AND currency_code = NEW.currency_code;
-    ELSEIF NEW.status_id IN (2, 4) THEN
-        UPDATE user_balances
-        SET total_confirmed = total_confirmed + NEW.amount
-        WHERE user_id = NEW.user_id AND currency_code = NEW.currency_code;
+    INSERT INTO user_balances (user_id, currency_code) VALUES (p_uid, p_curr)
+    ON DUPLICATE KEY UPDATE user_id = user_id;
+    UPDATE user_balances SET
+        total_proposed = total_proposed + IF(p_status = 1, p_amt * p_mod, 0),
+        total_ratified = total_ratified + IF(p_status = 2, p_amt * p_mod, 0),
+        total_disputed = total_disputed + IF(p_status = 3, p_amt * p_mod, 0),
+        total_settled  = total_settled  + IF(p_status = 4, p_amt * p_mod, 0),
+        total_spent    = total_spent    + IF(p_type = 1 AND p_amt > 0, p_amt * p_mod, 0)
+    WHERE user_id = p_uid AND currency_code = p_curr;
+    IF p_gid IS NOT NULL THEN
+        INSERT INTO group_user_balances (group_id, user_id, currency_code, net_balance, total_contributed)
+        VALUES (p_gid, p_uid, p_curr, p_amt * p_mod, IF(p_type = 1 AND p_amt > 0, p_amt * p_mod, 0))
+        ON DUPLICATE KEY UPDATE
+            net_balance = net_balance + (p_amt * p_mod),
+            total_contributed = total_contributed + IF(p_type = 1 AND p_amt > 0, p_amt * p_mod, 0);
     END IF;
 END //
-CREATE TRIGGER after_ledger_update
-AFTER UPDATE ON ledger
-FOR EACH ROW
+CREATE TRIGGER after_ledger_insert AFTER INSERT ON ledger FOR EACH ROW
 BEGIN
-    IF OLD.status_id = 1 THEN
-        UPDATE user_balances SET total_pending = total_pending - OLD.amount
-        WHERE user_id = OLD.user_id AND currency_code = OLD.currency_code;
-    ELSEIF OLD.status_id IN (2, 4) THEN
-        UPDATE user_balances SET total_confirmed = total_confirmed - OLD.amount
-        WHERE user_id = OLD.user_id AND currency_code = OLD.currency_code;
-    END IF;
-    IF NEW.status_id = 1 THEN
-        UPDATE user_balances SET total_pending = total_pending + NEW.amount
-        WHERE user_id = NEW.user_id AND currency_code = NEW.currency_code;
-    ELSEIF NEW.status_id IN (2, 4) THEN
-        UPDATE user_balances SET total_confirmed = total_confirmed + NEW.amount
-        WHERE user_id = NEW.user_id AND currency_code = NEW.currency_code;
-    END IF;
+    CALL sync_all_balances(NEW.user_id, NEW.group_id, NEW.currency_code, NEW.amount, NEW.status_id, NEW.type_id, 1);
 END //
-CREATE TRIGGER after_ledger_delete
-AFTER DELETE ON ledger
-FOR EACH ROW
+CREATE TRIGGER after_ledger_update AFTER UPDATE ON ledger FOR EACH ROW
 BEGIN
-    IF OLD.status_id = 1 THEN
-        UPDATE user_balances SET total_pending = total_pending - OLD.amount
-        WHERE user_id = OLD.user_id AND currency_code = OLD.currency_code;
-    ELSEIF OLD.status_id IN (2, 4) THEN
-        UPDATE user_balances SET total_confirmed = total_confirmed - OLD.amount
-        WHERE user_id = OLD.user_id AND currency_code = OLD.currency_code;
-    END IF;
+    CALL sync_all_balances(OLD.user_id, OLD.group_id, OLD.currency_code, OLD.amount, OLD.status_id, OLD.type_id, -1);
+    CALL sync_all_balances(NEW.user_id, NEW.group_id, NEW.currency_code, NEW.amount, NEW.status_id, NEW.type_id, 1);
+END //
+CREATE TRIGGER after_ledger_delete AFTER DELETE ON ledger FOR EACH ROW
+BEGIN
+    CALL sync_all_balances(OLD.user_id, OLD.group_id, OLD.currency_code, OLD.amount, OLD.status_id, OLD.type_id, -1);
 END //
 DELIMITER ;
-
-