Budget-first planning
Adds each reserved delay only when it fits inside the configured wait budget, then identifies the next delay that would exceed it.
Day 035 / APIs / Reliability
Retry Budget Calculator
/ Overview
A dependency-free Python CLI that calculates how many capped exponential-backoff retries fit inside a fixed wait budget, with an optional conservative jitter allowance.
Retry settings are easy to choose in isolation, but a growing backoff sequence can silently exceed an application's time budget. The distinction between retries and total attempts also creates avoidable planning mistakes.
/ Provided servicesClear thinking.
Clear thinking.
Practical delivery.
Bounded backoff model
Models a configurable multiplier and delay ceiling while rejecting unbounded or non-finite timing inputs.
Honest timing boundary
Covers waiting only; operation time, network latency and successful delivery are explicitly outside the calculation.
/ Solution
Retry Budget Calculator validates bounded timing inputs, applies capped exponential backoff, optionally reserves a worst-case jitter allowance and reports the delays that fit. It uses precise decimal arithmetic, produces readable or JSON output and never sends a network request.
/ Impact
Fixed wait-budget planning
Capped exponential backoff
Conservative jitter allowance
Retries separated from total attempts
Readable and JSON reports
Twelve standard-library tests included
Python standard library
Argparse, dataclasses, Decimal and JSON provide the complete dependency-free command-line workflow.
API reliability
Models capped exponential backoff, retry counts, total attempts and conservative jitter reservation.
Unittest
Twelve tests cover exact budgets, caps, jitter rounding, invalid inputs, text scope and CLI JSON output.