feat(hub): add SQLAlchemy 2.0 async DB layer + Alembic

Models: User, Node, Group, GroupMember, GEKBundle, RefreshToken, IPLog.
Engine configurable via MESHBAY_DATABASE_URL (asyncpg/aiosqlite).
Alembic async env.py + initial_schema migration autogenerated.

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

4 files changed, 221 insertions, 0 deletions

diff --git a/packages/meshbay-hub/src/meshbay_hub/db/migrations/README b/packages/meshbay-hub/src/meshbay_hub/db/migrations/README
new file mode 100644
index 0000000..98e4f9c
--- /dev/null
+++ b/packages/meshbay-hub/src/meshbay_hub/db/migrations/README
@@ -0,0 +1 @@
+Generic single-database configuration.
\ No newline at end of file
diff --git a/packages/meshbay-hub/src/meshbay_hub/db/migrations/env.py b/packages/meshbay-hub/src/meshbay_hub/db/migrations/env.py
new file mode 100644
index 0000000..f572716
--- /dev/null
+++ b/packages/meshbay-hub/src/meshbay_hub/db/migrations/env.py
@@ -0,0 +1,65 @@
+"""Alembic env.py — async-aware, reads DATABASE_URL from environment."""
+
+import asyncio
+import os
+from logging.config import fileConfig
+
+from sqlalchemy import pool
+from sqlalchemy.engine import Connection
+from sqlalchemy.ext.asyncio import async_engine_from_config
+
+from alembic import context
+
+from meshbay_hub.db.models import Base
+
+config = context.config
+
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+target_metadata = Base.metadata
+
+# Allow override via env var (production uses asyncpg, tests may use aiosqlite)
+db_url = os.environ.get(
+    "MESHBAY_DATABASE_URL",
+    "postgresql+asyncpg://meshbay:meshbay@localhost/meshbay_hub",
+)
+config.set_main_option("sqlalchemy.url", db_url)
+
+
+def run_migrations_offline() -> None:
+    context.configure(
+        url=db_url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def do_run_migrations(connection: Connection) -> None:
+    context.configure(connection=connection, target_metadata=target_metadata)
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+async def run_async_migrations() -> None:
+    connectable = async_engine_from_config(
+        config.get_section(config.config_ini_section, {}),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+    async with connectable.connect() as connection:
+        await connection.run_sync(do_run_migrations)
+    await connectable.dispose()
+
+
+def run_migrations_online() -> None:
+    asyncio.run(run_async_migrations())
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()
diff --git a/packages/meshbay-hub/src/meshbay_hub/db/migrations/script.py.mako b/packages/meshbay-hub/src/meshbay_hub/db/migrations/script.py.mako
new file mode 100644
index 0000000..1101630
--- /dev/null
+++ b/packages/meshbay-hub/src/meshbay_hub/db/migrations/script.py.mako
@@ -0,0 +1,28 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision: str = ${repr(up_revision)}
+down_revision: Union[str, Sequence[str], None] = ${repr(down_revision)}
+branch_labels: Union[str, Sequence[str], None] = ${repr(branch_labels)}
+depends_on: Union[str, Sequence[str], None] = ${repr(depends_on)}
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    ${downgrades if downgrades else "pass"}
diff --git a/packages/meshbay-hub/src/meshbay_hub/db/migrations/versions/d28b9caf9f07_initial_schema.py b/packages/meshbay-hub/src/meshbay_hub/db/migrations/versions/d28b9caf9f07_initial_schema.py
new file mode 100644
index 0000000..d4a9aa6
--- /dev/null
+++ b/packages/meshbay-hub/src/meshbay_hub/db/migrations/versions/d28b9caf9f07_initial_schema.py
@@ -0,0 +1,127 @@
+"""initial_schema
+
+Revision ID: d28b9caf9f07
+Revises: 
+Create Date: 2026-08-09 04:35:07.120021
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = 'd28b9caf9f07'
+down_revision: Union[str, Sequence[str], None] = None
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('users',
+    sa.Column('id', sa.String(length=36), nullable=False),
+    sa.Column('username', sa.String(length=64), nullable=False),
+    sa.Column('email', sa.String(length=256), nullable=False),
+    sa.Column('pw_hash', sa.LargeBinary(), nullable=False),
+    sa.Column('pw_salt', sa.LargeBinary(), nullable=False),
+    sa.Column('pk_ed25519', sa.String(length=64), nullable=False),
+    sa.Column('pk_x25519', sa.String(length=64), nullable=False),
+    sa.Column('hub_id', sa.String(length=128), nullable=False),
+    sa.Column('status', sa.String(length=16), nullable=False),
+    sa.Column('created_at', sa.DateTime(timezone=True), nullable=False),
+    sa.PrimaryKeyConstraint('id'),
+    sa.UniqueConstraint('username')
+    )
+    op.create_index('ix_users_email', 'users', ['email'], unique=False)
+    op.create_index('ix_users_username', 'users', ['username'], unique=False)
+    op.create_table('groups',
+    sa.Column('id', sa.String(length=36), nullable=False),
+    sa.Column('name', sa.String(length=128), nullable=False),
+    sa.Column('admin_id', sa.String(length=36), nullable=False),
+    sa.Column('visibility', sa.String(length=16), nullable=False),
+    sa.Column('join_policy', sa.String(length=16), nullable=False),
+    sa.Column('status', sa.String(length=16), nullable=False),
+    sa.Column('created_at', sa.DateTime(timezone=True), nullable=False),
+    sa.ForeignKeyConstraint(['admin_id'], ['users.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index('ix_groups_name', 'groups', ['name'], unique=False)
+    op.create_table('ip_logs',
+    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+    sa.Column('user_id', sa.String(length=36), nullable=True),
+    sa.Column('event', sa.String(length=32), nullable=False),
+    sa.Column('ip_address', sa.String(length=45), nullable=False),
+    sa.Column('detail', sa.String(length=256), nullable=True),
+    sa.Column('timestamp', sa.DateTime(timezone=True), nullable=False),
+    sa.ForeignKeyConstraint(['user_id'], ['users.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index('ix_ip_logs_ip', 'ip_logs', ['ip_address'], unique=False)
+    op.create_index('ix_ip_logs_timestamp', 'ip_logs', ['timestamp'], unique=False)
+    op.create_index('ix_ip_logs_user_id', 'ip_logs', ['user_id'], unique=False)
+    op.create_table('nodes',
+    sa.Column('id', sa.String(length=36), nullable=False),
+    sa.Column('user_id', sa.String(length=36), nullable=False),
+    sa.Column('pk_node', sa.String(length=64), nullable=False),
+    sa.Column('endpoint_hint', sa.String(length=128), nullable=True),
+    sa.Column('announced_at', sa.DateTime(timezone=True), nullable=False),
+    sa.ForeignKeyConstraint(['user_id'], ['users.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index('ix_nodes_user_id', 'nodes', ['user_id'], unique=False)
+    op.create_table('refresh_tokens',
+    sa.Column('id', sa.String(length=36), nullable=False),
+    sa.Column('user_id', sa.String(length=36), nullable=False),
+    sa.Column('token_hash', sa.String(length=64), nullable=False),
+    sa.Column('expires_at', sa.DateTime(timezone=True), nullable=False),
+    sa.Column('created_at', sa.DateTime(timezone=True), nullable=False),
+    sa.Column('revoked', sa.Boolean(), nullable=False),
+    sa.ForeignKeyConstraint(['user_id'], ['users.id'], ),
+    sa.PrimaryKeyConstraint('id'),
+    sa.UniqueConstraint('token_hash')
+    )
+    op.create_index('ix_refresh_tokens_hash', 'refresh_tokens', ['token_hash'], unique=False)
+    op.create_table('gek_bundles',
+    sa.Column('group_id', sa.String(length=36), nullable=False),
+    sa.Column('user_id', sa.String(length=36), nullable=False),
+    sa.Column('pk_eph_b64', sa.String(length=64), nullable=False),
+    sa.Column('nonce_b64', sa.String(length=32), nullable=False),
+    sa.Column('wrapped_b64', sa.String(length=128), nullable=False),
+    sa.Column('stored_at', sa.DateTime(timezone=True), nullable=False),
+    sa.ForeignKeyConstraint(['group_id'], ['groups.id'], ),
+    sa.ForeignKeyConstraint(['user_id'], ['users.id'], ),
+    sa.PrimaryKeyConstraint('group_id', 'user_id')
+    )
+    op.create_table('group_members',
+    sa.Column('group_id', sa.String(length=36), nullable=False),
+    sa.Column('user_id', sa.String(length=36), nullable=False),
+    sa.Column('joined_at', sa.DateTime(timezone=True), nullable=False),
+    sa.ForeignKeyConstraint(['group_id'], ['groups.id'], ),
+    sa.ForeignKeyConstraint(['user_id'], ['users.id'], ),
+    sa.PrimaryKeyConstraint('group_id', 'user_id')
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_table('group_members')
+    op.drop_table('gek_bundles')
+    op.drop_index('ix_refresh_tokens_hash', table_name='refresh_tokens')
+    op.drop_table('refresh_tokens')
+    op.drop_index('ix_nodes_user_id', table_name='nodes')
+    op.drop_table('nodes')
+    op.drop_index('ix_ip_logs_user_id', table_name='ip_logs')
+    op.drop_index('ix_ip_logs_timestamp', table_name='ip_logs')
+    op.drop_index('ix_ip_logs_ip', table_name='ip_logs')
+    op.drop_table('ip_logs')
+    op.drop_index('ix_groups_name', table_name='groups')
+    op.drop_table('groups')
+    op.drop_index('ix_users_username', table_name='users')
+    op.drop_index('ix_users_email', table_name='users')
+    op.drop_table('users')
+    # ### end Alembic commands ###