Shardeum, an autoscaling layer-1 blockchain ecosystem, announces the launch of Stage 4 of its Incentivized Testnet (ITN).Stage 4 will continue to test for vulnerabilities and network issues, solidifying the network code ahead of Mainnet.The previous three stages saw over 17 million transactions, 99k participants, and 22k validators.After ITN Stage 4, Shardeum will proceed with a code freeze and announce an upcoming node sale.