Quickstart

See Installation for prerequisites and install instructions.

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Python API

Use the async dccd.Client as a context manager. It resolves the config (via $XDG_CONFIG_HOME/dccd/config.yml or ./config.yml) and wires every exchange adapter.

import asyncio
from dccd import Client


async def main():
    async with Client() as c:
        # Backfill hourly OHLC candles (resumes from the last stored bar).
        result = await c.backfill("binance", "BTC/USDT", "ohlc",
                                  span=3600, start="last")
        print(result["rows_written"], "rows")

        # Read them back as a Polars DataFrame.
        df = c.read("binance", "BTC/USDT", "ohlc", span=3600)
        print(df.tail())


asyncio.run(main())

start accepts "last" (resume), "origin" (full history), an ISO date ("2024-01-01"), or a nanosecond integer. data_type is "ohlc", "trades" or "orderbook".

Trades backfills are cursor-paginated: the engine follows each exchange’s cursor until the requested window is fully drained.

Live streaming

import asyncio
from dccd import Client

async def main():
    async with Client() as c:
        stop = asyncio.Event()
        asyncio.get_event_loop().call_later(60, stop.set)  # stop after 60s
        await c.stream("binance", "BTC/USDT", "trades", stop_event=stop)

asyncio.run(main())

CLI

# One-off backfill
dccd backfill -e binance -s BTC/USDT -t ohlc --span 3600 --start last

# Run all stream jobs from the config
dccd stream

# Full daemon (scheduler + streams + web UI)
dccd start

# Inspect what is stored
dccd inventory

See CLI Reference for the full command reference and Configuration Reference for the YAML config.