Cargo Features

solana-send-transaction-service has no features set by default.

[dependencies]
solana-send-transaction-service = { version = "4.0.0-beta.2", features = ["agave-unstable-api", "dev-context-only-utils"] }
agave-unstable-api
dev-context-only-utils = solana-net-utils

Features from optional dependencies

In crates that don't use the dep: syntax, optional dependencies automatically become Cargo features. These features may have been created by mistake, and this functionality may be removed in the future.

solana-net-utils dev-context-only-utils?