tst.dev, a simple API for testing

use it for:

• error handling: return specific HTTP status codes, for example https://tst.dev/api/status/404
• chaos engineering: return a random HTTP status code with https://tst.dev/api/random
• latency simulation: specify a delay with https://tst.dev/api/delay?ms=3000
• performance/stress testing: return a large JSON payload with https://tst.dev/api/payload
• other things to be added soon