> ## Documentation Index
> Fetch the complete documentation index at: https://docs.bravadotrade.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Copy-Trading and Social Trading Products

> Build a copy-trading or social trading product on prediction markets with the Bravado Copytrade API.

## The problem

Retail interest in prediction markets is high but sophistication is uneven. A product that lets a user pick a top trader and automatically mirror their fills combines a proven UX pattern (Etoro-style copy trading) with a market that has no native copy-trading feature. Building this from scratch requires watching every fill on-chain, replaying it against a follower wallet, handling partial fills, and reconciling.

## What Bravado provides

The Copytrade API is a purpose-built engine that:

* Subscribes a follower wallet to a leader wallet's fills.
* Mirrors each leader fill according to configurable sizing modes: `proportional`, `fixed`, or `capped`.
* Enforces per-fill and per-day notional limits.
* Restricts mirroring by category, market, or outcome.
* Emits mirrored fill events with cross-references to the leader's original fill.

Polymarket does not offer a native equivalent. Every copy-trading product on Polymarket is running its own version of this engine or is using Bravado.

## APIs used

| API                                      | What a copy-trading product uses it for                                                        |
| ---------------------------------------- | ---------------------------------------------------------------------------------------------- |
| [Copytrade API](/products/copytrade-api) | Subscriptions, sizing modes, filters, risk controls, and simulation                            |
| [Data API](/products/data-api)           | Evaluating a prospective leader before subscribing: PnL curve, win rate, and category exposure |
| [Trade API](/products/trade-api)         | The execution layer mirrored fills run through, plus balances and positions for the follower   |

## Worked example

Provision a follower, subscribe to a leader, and print mirrored fills:

```python theme={null}
import os, uuid, time, requests

API = "https://bravado-api-k7kaq.ondigitalocean.app"
KEY = os.environ["BRAVADO_API_KEY"]
H = {"Authorization": f"Bearer {KEY}", "Content-Type": "application/json"}

def new_key():
    return {"Idempotency-Key": str(uuid.uuid4())}

# 1. Pick a leader from the leaderboard.
leaderboard = requests.get(f"{API}/leaderboard?window=30d&order=pnl&limit=1", headers=H).json()
leader = leaderboard["traders"][0]["address"]

# 2. Subscribe with proportional sizing and a per-fill cap.
sub = requests.post(f"{API}/v2/trade/copytrade/subscriptions", headers={**H, **new_key()}, json={
    "leader_address": leader,
    "sizing_mode": "proportional",
    "sizing_factor": "0.10",
    "max_notional_per_fill": "100.00",
    "daily_notional_limit": "1000.00",
}).json()

# 3. Stream mirrored fills.
seen = set()
while True:
    fills = requests.get(
        f"{API}/v2/trade/copytrade/subscriptions/{sub['subscription_id']}/fills?limit=100",
        headers=H,
    ).json()

    for f in fills["fills"]:
        if f["fill_id"] in seen:
            continue
        seen.add(f["fill_id"])
        print(f"[{f['created_at']}] mirrored leader fill {f['leader_fill_id']}: "
              f"{f['side']} {f['filled_size']} @ ${f['average_price']}")
    time.sleep(5)
```

## Product patterns

Two common product shapes on top of the Copytrade API:

1. **Follow-a-trader.** User picks one leader from a curated list. Simple, low-cognitive-load onboarding.
2. **Basket.** User subscribes to many leaders at once with different sizing weights. Reduces single-trader risk.

Both are single-API-call operations once a follower is provisioned. See the [guide](/products/copytrade-api) for a starter implementation.

## Related

* [Guide: Build a copy-trading bot](/guides/copy-trading-bot-50-lines)
* [Guide: Track a whale wallet](/guides/track-whale-wallet)
* [Concept: Copy trading](/products/copytrade-api)
* [Copytrade API reference](/api/copytrade/overview)