1. A computer-implemented method, comprising: analyzing source code comprising a plurality of instructions for an application; identifying, based on said analyzing, a sequence of instructions configured to execute atomically; replacing the identified sequence of instructions with an alternate sequence of instructions, wherein the alternate sequence of instructions is executable to implement: determining, at runtime, one of a plurality of different transaction implementations for atomic execution of the identified sequence of instructions; and attempting to execute the determined one of the different transaction implementations to atomically execute the identified sequence of instructions.