Intermittently powered energy-harvesting devices enable new applications in inaccessible environments. Program executions must be robust to unpredictable power failures, introducing new challenges in programmability and correctness. One hard problem is that input operations have implicit constraints, embedded in the behavior of continuously powered executions, on when input values can be collected and used. We identify two key properties—freshness (i.e., uses of inputs must satisfy the same time constraints as in continuous executions) and temporal consistency (i.e., the collection of a set of inputs must satisfy the same time constraints as in continuous executions). We show that these properties can be enforced using atomic regions. We develop Ocelot, an LLVM-based analysis and transformation tool targeting Rust, to automatically enforce these properties. Ocelot provides the programmer with annotations to express these constraints and infers atomic region placement in a program to satisfy them. We formalize these properties and Ocelot’s design and show that Ocelot enables correct execution at little performance cost and low programmer effort.