the station / chart
The chart
Eight sectors seen from above. You are in the middle with
nothing adopted, and distance from the centre is prerequisite depth — how far
along a sector you have actually got. A control that moves two sectors at once
sits between them, which is why the lines cut across the disc.
Pick any control to plot a course to it. The chart lights the
prerequisites in the order you would do them, and fills in the position that
course would leave you in across all eight sectors.
01 FEEDBACK LATENCY 02 REVERSIBILITY 03 BLAST RADIUS 04 DETERMINISM 05 OBSERVABILITY 06 CHANGE COUPLING 07 KNOWLEDGE DISTRIBUTION 08 SLACK Alert on what users feel, not on what machines feel — tier II, cost medium Book the time for the boring fix before the week fills — tier II, cost high Turn it on for a cohort before everyone — tier III, cost medium Deploy dark; release with a flag — tier II, cost medium Migrate in expand and contract, never in place — tier IV, cost medium Reproduce the bug in a failing test before fixing it — tier IV, cost low Every flag gets a removal deadline when it is created — tier III, cost low Tests bring their own world — tier II, cost high Every deploy leaves a mark in the telemetry — tier III, cost low Model-check the algorithm you cannot test your way out of — tier III, cost high Mutation-test the diff, not the repo — tier I, cost high Give every component an owner, and watch the drive-by edits — tier II, cost low One command builds and tests the project from a clean checkout — tier IV, cost low Rolling back is one step, and it is practised — tier III, cost medium Pin every dependency to an exact version — tier II, cost low Make it safe to say the thing nobody wants to hear — tier III, cost high A quarantined test has a deadline, not a drawer — tier II, cost low A review with no discussion is not a review — tier II, cost low A second person has actually done the risky task — tier II, cost medium Shape the suite by what each test costs and can catch — tier IV, cost medium Put static analysis in the review, not in a backlog — tier III, cost medium Every change runs the suite before a human looks at it — tier III, cost medium Know the truck factor of anything you cannot afford to lose — tier II, cost medium Branches live hours, not weeks — tier II, cost medium Write down decisions, with the reasoning and the alternatives — tier IV, cost low YOU
Course plotting needs JavaScript. The same information,
ordered and linkable, is on the station index .