curl --request POST \
  --url https://demo-futures.kraken.com/derivatives/api/v3/portfolio-margining/simulate \
  --header 'APIKey: <api-key>' \
  --header 'Authent: <api-key>'

import requests

url = "https://demo-futures.kraken.com/derivatives/api/v3/portfolio-margining/simulate"

headers = {
    "APIKey": "<api-key>",
    "Authent": "<api-key>"
}

response = requests.post(url, headers=headers)

print(response.text)

const options = {method: 'POST', headers: {APIKey: '<api-key>', Authent: '<api-key>'}};

fetch('https://demo-futures.kraken.com/derivatives/api/v3/portfolio-margining/simulate', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://demo-futures.kraken.com/derivatives/api/v3/portfolio-margining/simulate"

	req, _ := http.NewRequest("POST", url, nil)

	req.Header.Add("APIKey", "<api-key>")
	req.Header.Add("Authent", "<api-key>")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

{
  "maintenanceMargin": 123,
  "initialMargin": 123,
  "pnl": 123,
  "portfolioMarginBreakdown": {
    "totalCrossAssetNettedMarketRisk": 123,
    "totalMarketRisk": 123,
    "totalAbsoluteOptionPositionDeltaNotional": 123,
    "netPortfolioDelta": 123,
    "totalPremium": 123,
    "isBuyOnly": true,
    "futuresMaintenanceMargin": 123,
    "totalScenarioPnls": [
      123
    ]
  },
  "greeks": {},
  "result": "success",
  "serverTime": "2020-08-27T17:03:33.196Z"
}