curl -X POST "https://api.keplars.com/api/v1/send-email/instant" \
  -H "Authorization: Bearer $KEPLARS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"to":["[email protected]"],"template_id":"your-template-id","params":{"firstName":"Jane","orderNumber":"ORD-9912","shipDate":"2026-06-20"}}'

const res = await fetch(
  'https://api.keplars.com/api/v1/send-email/instant',
  {
    method: 'POST',
    headers: {
      Authorization: `Bearer ${process.env.KEPLARS_API_KEY}`,
      'Content-Type': 'application/json',
    },
    body: JSON.stringify({
    to: ['[email protected]'],
    template_id: 'your-template-id',
    params: { firstName: 'Jane', orderNumber: 'ORD-9912', shipDate: '2026-06-20' },
  }),
  },
);
const { data } = await res.json();

import requests, os
res = requests.post(
    'https://api.keplars.com/api/v1/send-email/instant',
    json={
        'to': ['[email protected]'],
        'template_id': 'your-template-id',
        'params': {'firstName': 'Jane', 'orderNumber': 'ORD-9912', 'shipDate': '2026-06-20'},
    },
    headers={'Authorization': f'Bearer {os.environ["KEPLARS_API_KEY"]}'},
)
data = res.json()['data']

package main

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

func main() {
    body := bytes.NewBufferString(`{"to":["[email protected]"],"template_id":"your-template-id","params":{"firstName":"Jane","orderNumber":"ORD-9912","shipDate":"2026-06-20"}}`)
    req, _ := http.NewRequest("POST",
        "https://api.keplars.com/api/v1/send-email/instant", body)
    req.Header.Set("Authorization", "Bearer "+os.Getenv("KEPLARS_API_KEY"))
    req.Header.Set("Content-Type", "application/json")
    resp, _ := (&http.Client{}).Do(req)
    defer resp.Body.Close()
    b, _ := io.ReadAll(resp.Body)
    fmt.Println(string(b))
}

<?php
$ch = curl_init('https://api.keplars.com/api/v1/send-email/instant');
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_POST           => true,
    CURLOPT_POSTFIELDS     => json_encode([
        'to' => ['[email protected]'],
        'template_id' => 'your-template-id',
        'params' => ['firstName' => 'Jane', 'orderNumber' => 'ORD-9912', 'shipDate' => '2026-06-20'],
    ]),
    CURLOPT_HTTPHEADER     => [
        'Authorization: Bearer ' . getenv('KEPLARS_API_KEY'),
        'Content-Type: application/json',
    ],
]);
$data = json_decode(curl_exec($ch), true)['data'];
curl_close($ch);

using System.Net.Http;
using System.Net.Http.Json;

var client = new HttpClient();
client.DefaultRequestHeaders.Add(
    "Authorization", $"Bearer {Environment.GetEnvironmentVariable("KEPLARS_API_KEY")}"
);
var response = await client.PostAsJsonAsync(
    "https://api.keplars.com/api/v1/send-email/instant",
    new
{
    to = new[] { "[email protected]" },
    template_id = "your-template-id",
    params = new { firstName = "Jane", orderNumber = "ORD-9912", shipDate = "2026-06-20" }
}
);
var body = await response.Content.ReadAsStringAsync();

use reqwest::Client;
use serde_json::json;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();
    let res = client
        .post("https://api.keplars.com/api/v1/send-email/instant")
        .header("Authorization", format!("Bearer {}", std::env::var("KEPLARS_API_KEY")?))
        .json(&json!({
    "to": [
        "[email protected]"
    ],
    "template_id": "your-template-id",
    "params": {
        "firstName": "Jane",
        "orderNumber": "ORD-9912",
        "shipDate": "2026-06-20"
    }
}))
        .send()
        .await?;
    let data: serde_json::Value = res.json().await?;
    println!("{}", data);
    Ok(())
}

#include <curl/curl.h>
#include <cstdlib>
#include <string>

int main() {
    CURL* curl = curl_easy_init();
    std::string auth = std::string("Authorization: Bearer ") + std::getenv("KEPLARS_API_KEY");
    const char* payload = "{\"to\":[\"[email protected]\"],\"template_id\":\"your-template-id\",\"params\":{\"firstName\":\"Jane\",\"orderNumber\":\"ORD-9912\",\"shipDate\":\"2026-06-20\"}}";
    struct curl_slist* headers = nullptr;
    headers = curl_slist_append(headers, auth.c_str());
    headers = curl_slist_append(headers, "Content-Type: application/json");
    curl_easy_setopt(curl, CURLOPT_URL, "https://api.keplars.com/api/v1/send-email/instant");
    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
    curl_easy_setopt(curl, CURLOPT_POSTFIELDS, payload);
    curl_easy_perform(curl);
    curl_slist_free_all(headers);
    curl_easy_cleanup(curl);
}

#include <curl/curl.h>
#include <stdio.h>
#include <stdlib.h>

int main(void) {
    CURL* curl = curl_easy_init();
    char auth[256];
    snprintf(auth, sizeof(auth), "Authorization: Bearer %s", getenv("KEPLARS_API_KEY"));
    const char* payload = "{\"to\":[\"[email protected]\"],\"template_id\":\"your-template-id\",\"params\":{\"firstName\":\"Jane\",\"orderNumber\":\"ORD-9912\",\"shipDate\":\"2026-06-20\"}}";
    struct curl_slist* headers = NULL;
    headers = curl_slist_append(headers, auth);
    headers = curl_slist_append(headers, "Content-Type: application/json");
    curl_easy_setopt(curl, CURLOPT_URL, "https://api.keplars.com/api/v1/send-email/instant");
    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);
    curl_easy_setopt(curl, CURLOPT_POSTFIELDS, payload);
    curl_easy_perform(curl);
    curl_slist_free_all(headers);
    curl_easy_cleanup(curl);
    return 0;
}