1. A computer system for managing time constraints in a circuit, the computer system comprising: one or more computer processors; one or more non-transitory computer readable storage media; and program instructions stored on the one or more non-transitory computer readable storage media for execution by at least one of the one or more computer processors, the program instructions comprising: program instructions to create an initial placement design in a circuit; program instructions to determine based on the created initial placement design whether a first criteria is met, wherein the first criteria comprises a design parameter at a first predefined threshold; program instructions to, in response to determining that the first criteria is met, initiate a first checkpoint procedure, wherein the first checkpoint procedure comprises a two-pass flow, in which: a first pass grouping based on a location of a group of macros and clustering of the group of macros is iteratively performed until a distance parameter exceeds a predetermined threshold; and a second pass grouping is based on a time constraint, wherein pin list filtering is performed to generate a first shortened pin list; program instructions to, in response to determining that a first criteria is not met, perform an intermediate placement design; program instructions to determine whether a second criteria is met based on the intermediate placement design, wherein the second criteria comprises a second predefined threshold; program instructions to, in response to determining that the second criteria is met, initiate a second checkpoint procedure, wherein the second checkpoint procedure comprises: program instructions to gather a list of arrival times (ATs) and a list of expected time of arrival (ETA) for the group of macros; program instructions to perform pin list filtering to create a second shortened pin list; and program instructions to calculate an average and a standard deviation of the list of ATs and the list of ETA; and program instructions to perform design iterations using at least the first shortened pin list or the second shortened pin list if the first threshold or the second threshold is met respectively instead of an unfiltered pin list, to reach a final optimized stage, wherein the design iterations include: a detailed routability metrics evaluation, a buffering update, clocking and power related checks, and a fix-up of reliability issues.