feat: Implement community bounty boosting

backend/alembic/versions/005_add_bounty_boosts.py

@@ -0,0 +1,62 @@
+"""Add bounty_boosts table for community reward boosting.
+
+Revision ID: 005_bounty_boosts
+Revises: 004_contributor_webhooks
+Create Date: 2026-03-23
+"""
+
+from typing import Sequence, Union
+
+import sqlalchemy as sa
+from alembic import op
+
+revision: str = "005_bounty_boosts"
+down_revision: Union[str, None] = "004_contributor_webhooks"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.create_table(
+        "bounty_boosts",
+        sa.Column("id", sa.String(36), primary_key=True),
+        sa.Column(
+            "bounty_id",
+            sa.String(36),
+            sa.ForeignKey("bounties.id", ondelete="CASCADE"),
+            nullable=False,
+        ),
+        sa.Column("booster_wallet", sa.String(64), nullable=False),
+        sa.Column("amount", sa.Numeric(precision=20, scale=6), nullable=False),
+        sa.Column("status", sa.String(20), nullable=False, server_default="pending"),
+        sa.Column("tx_hash", sa.String(128), unique=True, nullable=True),
+        sa.Column("refund_tx_hash", sa.String(128), unique=True, nullable=True),
+        sa.Column(
+            "created_at",
+            sa.DateTime(timezone=True),
+            nullable=False,
+            server_default=sa.text("NOW()"),
+        ),
+        sa.Column(
+            "updated_at",
+            sa.DateTime(timezone=True),
+            nullable=False,
+            server_default=sa.text("NOW()"),
+        ),
+    )
+    op.create_index("ix_bounty_boosts_bounty_id", "bounty_boosts", ["bounty_id"])
+    op.create_index("ix_bounty_boosts_booster_wallet", "bounty_boosts", ["booster_wallet"])
+    op.create_index("ix_bounty_boosts_created_at", "bounty_boosts", ["created_at"])
+    op.create_index(
+        "ix_bounty_boosts_bounty_status",
+        "bounty_boosts",
+        ["bounty_id", "status"],
+    )
+
+
+def downgrade() -> None:
+    op.drop_index("ix_bounty_boosts_bounty_status", table_name="bounty_boosts")
+    op.drop_index("ix_bounty_boosts_created_at", table_name="bounty_boosts")
+    op.drop_index("ix_bounty_boosts_booster_wallet", table_name="bounty_boosts")
+    op.drop_index("ix_bounty_boosts_bounty_id", table_name="bounty_boosts")
+    op.drop_table("bounty_boosts")

backend/app/api/bounties.py

@@ -12,7 +12,16 @@
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.database import get_db
+from app.exceptions import BoostBelowMinimumError, BoostInvalidBountyError
+from app.models.boost import (
+    BoostRequest,
+    BoostResponse,
+    BoostListResponse,
+    BoostSummary,
+    BoostLeaderboardResponse,
+)
 from app.models.errors import ErrorResponse
+from app.services import boost_service
 from app.services.bounty_lifecycle_service import (
     LifecycleError,
     publish_bounty as _publish_bounty,
@@ -855,3 +864,62 @@
     except LifecycleError as exc:
         code = 404 if exc.code == "NOT_FOUND" else 400
         raise HTTPException(status_code=code, detail=exc.message)
+
+
+# ---------------------------------------------------------------------------
+# Boost endpoints
+# ---------------------------------------------------------------------------
+
+
+@router.post(
+    "/{bounty_id}/boost",
+    response_model=BoostResponse,
+    status_code=status.HTTP_201_CREATED,
+    summary="Boost a bounty reward",
+    responses={
+        400: {"model": ErrorResponse, "description": "Below minimum or invalid bounty"},
+        404: {"model": ErrorResponse, "description": "Bounty not found"},
+    },
+)
+async def boost_bounty(bounty_id: str, body: BoostRequest):
+    """Add $FNDRY to a bounty's prize pool.
+
+    The boosted amount goes into escrow alongside the original reward.
+    Minimum contribution is 1,000 $FNDRY. The bounty must be OPEN or
+    IN_PROGRESS. A Telegram notification is sent to the bounty owner.
+    """
+    try:
+        return await boost_service.create_boost(
+            bounty_id=bounty_id,
+            booster_wallet=body.booster_wallet,
+            amount=body.amount,
+            tx_hash=body.tx_hash,
+        )
+    except BoostBelowMinimumError as exc:
+        raise HTTPException(status_code=400, detail=str(exc))
+    except BoostInvalidBountyError as exc:
+        raise HTTPException(status_code=404, detail=str(exc))
+
+
+@router.get(
+    "/{bounty_id}/boosts",
+    response_model=BoostListResponse,
+    summary="List boosts for a bounty",
+)
+async def list_bounty_boosts(
+    bounty_id: str,
+    skip: int = Query(0, ge=0),
+    limit: int = Query(50, ge=1, le=100),
+):
+    """Return paginated boost history for a bounty (newest first)."""
+    return await boost_service.get_boosts(bounty_id, skip=skip, limit=limit)
+
+
+@router.get(
+    "/{bounty_id}/boost-leaderboard",
+    response_model=BoostLeaderboardResponse,
+    summary="Top boosters for a bounty",
+)
+async def bounty_boost_leaderboard(bounty_id: str):
+    """Return the top 20 boosters ranked by total $FNDRY contributed."""
+    return await boost_service.get_boost_leaderboard(bounty_id)

backend/app/database.py

@@ -175,6 +175,7 @@ async def init_db() -> None:
             from app.models.review import AIReviewScoreDB  # noqa: F401
             from app.models.lifecycle import BountyLifecycleLogDB  # noqa: F401
             from app.models.escrow import EscrowTable, EscrowLedgerTable  # noqa: F401
+            from app.models.boost import BountyBoostTable  # noqa: F401
 
             # NOTE: create_all is idempotent (skips existing tables). For
             # production schema changes use ``alembic upgrade head`` instead.

backend/app/exceptions.py

@@ -134,3 +134,24 @@ def __init__(self, message: str, tx_hash: str | None = None) -> None:
 
 class EscrowDoubleSpendError(EscrowError):
     """Raised when a funding transaction could not be confirmed on-chain."""
+
+
+# ---------------------------------------------------------------------------
+# Boost exceptions
+# ---------------------------------------------------------------------------
+
+
+class BoostError(Exception):
+    """Base class for all bounty-boost errors."""
+
+
+class BoostBelowMinimumError(BoostError):
+    """Raised when a boost amount is below the 1,000 $FNDRY minimum."""
+
+
+class BoostInvalidBountyError(BoostError):
+    """Raised when the target bounty does not exist or is not boostable."""
+
+
+class BoostNotFoundError(BoostError):
+    """Raised when a boost ID does not exist."""

backend/app/models/boost.py

@@ -0,0 +1,147 @@
+"""ORM model and Pydantic schemas for bounty reward boosts.
+
+Community members can boost a bounty's prize pool by contributing
+$FNDRY. All boost amounts go into escrow alongside the original reward
+and are refunded if the bounty expires without completion.
+
+Boost lifecycle::
+
+    PENDING → CONFIRMED (on-chain tx verified)
+        |
+        +→ REFUNDED  (bounty expired / cancelled)
+"""
+
+from __future__ import annotations
+
+import re
+import uuid
+from datetime import datetime, timezone
+from enum import Enum
+from typing import Optional
+
+import sqlalchemy as sa
+from sqlalchemy import Column, DateTime, Index, String
+from pydantic import BaseModel, Field, field_validator
+
+from app.database import Base
+
+_BASE58_RE = re.compile(r"^[1-9A-HJ-NP-Za-km-z]{32,44}$")
+MINIMUM_BOOST_AMOUNT = 1_000.0
+
+
+def _now() -> datetime:
+    return datetime.now(timezone.utc)
+
+
+# ---------------------------------------------------------------------------
+# Boost status enum
+# ---------------------------------------------------------------------------
+
+
+class BoostStatus(str, Enum):
+    PENDING = "pending"
+    CONFIRMED = "confirmed"
+    REFUNDED = "refunded"
+
+
+# ---------------------------------------------------------------------------
+# ORM model
+# ---------------------------------------------------------------------------
+
+
+class BountyBoostTable(Base):
+    """One row per community boost contribution to a bounty's prize pool."""
+
+    __tablename__ = "bounty_boosts"
+
+    id = Column(String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
+    bounty_id = Column(
+        String(36),
+        sa.ForeignKey("bounties.id", ondelete="CASCADE"),
+        nullable=False,
+        index=True,
+    )
+    booster_wallet = Column(String(64), nullable=False, index=True)
+    amount = Column(sa.Numeric(precision=20, scale=6), nullable=False)
+    status = Column(String(20), nullable=False, server_default=BoostStatus.PENDING.value)
+    tx_hash = Column(String(128), unique=True, nullable=True, index=True)
+    refund_tx_hash = Column(String(128), unique=True, nullable=True)
+    created_at = Column(DateTime(timezone=True), nullable=False, default=_now, index=True)
+    updated_at = Column(DateTime(timezone=True), nullable=False, default=_now, onupdate=_now)
+
+    __table_args__ = (
+        Index("ix_bounty_boosts_bounty_status", "bounty_id", "status"),
+    )
+
+
+# ---------------------------------------------------------------------------
+# Pydantic schemas
+# ---------------------------------------------------------------------------
+
+
+class BoostRequest(BaseModel):
+    """POST /bounties/{id}/boost request body."""
+
+    booster_wallet: str = Field(..., min_length=32, max_length=44)
+    amount: float = Field(..., gt=0)
+    tx_hash: Optional[str] = Field(None, description="On-chain SPL transfer signature")
+
+    @field_validator("booster_wallet")
+    @classmethod
+    def validate_wallet(cls, v: str) -> str:
+        if not _BASE58_RE.match(v):
+            raise ValueError("booster_wallet must be a valid Solana base-58 address")
+        return v
+
+    @field_validator("amount")
+    @classmethod
+    def validate_min_amount(cls, v: float) -> float:
+        if v < MINIMUM_BOOST_AMOUNT:
+            raise ValueError(f"Minimum boost is {MINIMUM_BOOST_AMOUNT:,.0f} $FNDRY")
+        return v
+
+
+class BoostResponse(BaseModel):
+    """Single boost entry."""
+
+    id: str
+    bounty_id: str
+    booster_wallet: str
+    amount: float
+    status: BoostStatus
+    tx_hash: Optional[str] = None
+    refund_tx_hash: Optional[str] = None
+    created_at: datetime
+
+
+class BoostListResponse(BaseModel):
+    """Paginated list of boosts for a bounty."""
+
+    boosts: list[BoostResponse]
+    total: int
+    total_boosted: float
+
+
+class BoostSummary(BaseModel):
+    """Reward summary shown on bounty detail: original + boosted amounts."""
+
+    original_amount: float
+    total_boosted: float
+    total_amount: float
+    boost_count: int
+
+
+class BoosterLeaderboardEntry(BaseModel):
+    """One entry in the per-bounty booster leaderboard."""
+
+    rank: int
+    booster_wallet: str
+    total_boosted: float
+    boost_count: int
+
+
+class BoostLeaderboardResponse(BaseModel):
+    """Top boosters for a single bounty."""
+
+    leaderboard: list[BoosterLeaderboardEntry]
+    total_boosted: float