For mins restart ? is app sleeping ? when data are transferred inbound & outbound ?

railway.toml here :

[build]
builder = "NIXPACKS"
nixpacksPlan = {"providers":["…"]}

[deploy]
numReplicas = 1
sleepApplication = false
restartPolicyType = "ON_FAILURE"
restartPolicyMaxRetries = 10

I don't know what plan you're on but if you're on the trial plan your app could be running out of the allowed memory (512mb on the trial).

Otherwise, if there's no logs, it just means you aren't logging the errors, try to add as much error handling and telemetry as you can!