Leaflet
Leaflet can display image layers from ReadyMap using the L.tileLayer function.
Note
ReadyMap can produce layers in both global-geodetic and spherical-mercator tiling schemes If you are loading a global-geodetic layer in Leaflet you must set the crs of the map object to L.CRS.EPSG4326
Here is a complete example of loading a ReadyMap TMS layer in Leaflet
<!DOCTYPE html>
<html>
<head>
<title>Leaflet ReadyMap</title>
<link rel="stylesheet" href="https://unpkg.com/leaflet@1.9.4/dist/leaflet.css" />
<script src="https://unpkg.com/leaflet@1.9.4/dist/leaflet.js"></script>
<style type="text/css">
#map {
position: absolute;
top: 0;
left: 0;
height: 100%;
width: 100%;
margin: 0;
overflow: hidden;
padding: 0;
}
</style>
</head>
<body>
<div id="map"></div>
<script>
var map = L.map('map', {
center: [0, 0],
zoom: 1,
crs: L.CRS.EPSG4326
});
L.tileLayer('https://readymap.org/readymap/tiles/1.0.0/7/{z}/{x}/{y}', {
tms: true
}).addTo(map);
</script>
</body>
</html>