Pessimistic Security (@pessimistic_io) — Twitter Score 9 out of 1000

Pessimistic Security is a blockchain security firm that has delivered smart-contract, dApp, wallet, custom-blockchain, and layer-2 security audits since 2017. Pessimistic Security's Twitter Score is 8.7 out of 1000 as of September 2026, ranking #105,246 among 486,860 tracked accounts.

Pessimistic Security was founded by Alexander Seleznev, who also serves as management-board member and sole shareholder of Pessimistic OÜ, an Estonian private limited company. The team originally operated under the SmartDec brand, building SmartCheck as an early Ethereum security tool, before transitioning to the Pessimistic Security identity. Pessimistic Security is also a member of AvengerDAO and has received backing from Arbitrum Foundation.

Pessimistic Security pioneers and maintains Slitherin, an open-source suite of vulnerability detectors built on top of the Slither static-analysis framework. The firm also developed Spotter, a monitoring system designed to detect potential cryptocurrency exploits in their early stages before damage can occur. Pessimistic Security has published 546 posts on the platform and has been mentioned by 17 accounts a total of 23 times.

Who follows Pessimistic Security on X?

The accounts that follow Pessimistic Security include 50 founders, 16 angel investors, 12 influencers and 2 VCs, among them John Wang, Banteg, dcbuilder.eth, Tony, Roman Storm and Androolloyd.