tastyware's paper trading API

[Graeme22]

I wanted to let people know I created a proprietary sandbox/paper trading system that mocks the Tastytrade API which allows for much better testing of strategies. It eliminates a lot of the restrictions of the current sandbox accounts: you can control fill behavior, positions don't get reset every 24 hours, buying power usage is realistic, handles margin, expiration, assignment/exercise, etc. Read about it here: https://tastyworks-api.readthedocs.io/en/latest/paper.html

To use it you'll write code like:

import os
from datetime import date
from decimal import Decimal

from tastytrade import Account, Session
from tastytrade.instruments import OptionType, get_option_chain
from tastytrade.order import FillBehavior, NewOrder, OrderAction, OrderTimeInForce, OrderType
from tastytrade.paper import PaperSession

session = Session(os.environ["TT_SECRET"], os.environ["TT_REFRESH"])
chain = get_option_chain(session, "SPY")[date(2025, 12, 12)]
option = next(
    c for c in chain if c.option_type == OptionType.PUT and round(c.strike_price) == 680
)

paper = PaperSession("my-api-key")
acc = await Account.get(paper)[0]
order = NewOrder(
    time_in_force=OrderTimeInForce.DAY,
    order_type=OrderType.LIMIT,
    legs=[option.build_leg(1, OrderAction.SELL_TO_OPEN)],
    price=Decimal("0.91"),
    behavior=FillBehavior.IMMEDIATE,
)
print(await acc.place_order(paper, order, dry_run=False))

The paper session can be used with almost all account-related endpoints to place orders, view positions, etc. and the normal OAuth sessions continue to be used for other endpoints.

Since I have to host a server for this there's a monthly subscription fee. Drop a comment below if you're curious! I've found that testing is currently a real pain point and I hope this will fix that.

[klaypigeon]

Well, I am just getting started with the sandbox and so far I have had zero success placing option orders. Any (presumably) valid order sits in a ROUTED state and never transitions to inflight or filled. So, this may or may not be something I am interested in. At this point I am still assuming it is just me being a newb.

[Ramneantu]

@klaypigeon Any success with getting fills? I had a decent experience last year getting sandbox orders filled, if their limit was below $3. However now, I am also just getting orders sitting in ROUTED. This is from my discussion with tastytrade support last year:

Orders statuses in the sandbox system are all determined by the order type and order price. The logic is as follows:
Market orders will always fill at a price of $1.
Limit orders with a price <= $3 will fill immediately.
Limit orders with a price between >= $3 will be Live and never fill.

They did also mention that they are actively working on the sandbox environment.

[Graeme22]

I think their environment only supports a few symbols to make things worse

[maneum1]

Ha, that is an interesting coincidence. I'm currently starting to work my way into the tastytrade api.
First of all I want to thank you @Graeme22 putting this API together, really great work.

Two thoughts on your initial question, I think the sandbox purpose is mainly to error prove code before it goes live. Its intent is not to practice trading like in a paper trading account.

Offering a tastytrade paper trading service might be something people will find interesting, but there is already free competition out there, Like thinkorswim (probably more, but TOS is the one I know and use).

Regarding the sandbox environment I'm ok with keeping it simple, meaning just a few symbols, but it should allow to test all facets of the API, at the end it is a testing bucket to verify any product using the api works as expected.

I'm at an really early stage working my way into the different functions.
My first attempt is trying to load customer data, and already running into issues.

While the live environment properly can use the session.get_customer() function the sandbox session fails because here tastytrade does only use a limited number of fields causing pydantic to raise errors when creating a Customer instance with the sandbox return data..

@Graeme22 Probably the next should go into a different place here (I'm not too experienced using the git website and repository features), and I'll change it according to your feedback.

As far I see it either new specific data classes for some of the sand box entities are defined or, some of the current existing classes need to be changed to require missing fields from the sandbox only as Optional. What do you prefer?

thanks
maneum1

[Graeme22]

Actually the point of the proprietary sandbox wouldn't really be paper trading (though it could be used for that), but rather better testing since the tastytrade provided sandbox sessions don't really work at all.

If you want to make specific fields the sandbox session doesn't return optional open a PR or an issue.

[maneum1]

Thanks for the feedback,
let me work on a fix for the sandbox problems I encounter.
I'll open a PR when I got it to work.

[Graeme22]

For those interested, this is now available here: https://tastyworks-api.readthedocs.io/en/latest/paper.html