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Performance and Maintainability with Continuous...
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Seth Walker
April 24, 2014
Technology
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Performance and Maintainability with Continuous Experimentation
Seth Walker
April 24, 2014
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Transcript
Performance and Maintainability with Continuous Experimentation @sethwalker sethwalker.me/talks/continuous-experimentation
@sethwalker Seth Walker Allison McKnight Jonathan Klein @sethwalker @aemcknig @jonathanklein
Daniel Espeset @danielespeset @dxna Daniel Na Lara Swanson @laraswanson
None
@sethwalker
@sethwalker 175 committers
@sethwalker 100 committers touch CSS & JS
@sethwalker
@sethwalker Confidence?
Operations
@sethwalker Feature Flags
@sethwalker $cfg['save_everything'] = 'staff'; // ... snip ... if (isEnabled('save_everything'))
{ writeToDB($everything); } else { throwAway($everything); }
@sethwalker $cfg['save_everything'] = '1%'; // ... snip ... if (isEnabled('save_everything'))
{ writeToDB($everything); } else { throwAway($everything); }
@sethwalker $cfg['save_everything'] = '5%'; // ... snip ... if (isEnabled('save_everything'))
{ writeToDB($everything); } else { throwAway($everything); }
@sethwalker $cfg['save_everything'] = '1%'; // ... snip ... if (isEnabled('save_everything'))
{ writeToDB($everything); } else { throwAway($everything); }
@sethwalker $cfg['save_everything'] = '5%'; // ... snip ... if (isEnabled('save_everything'))
{ writeToDB($everything); } else { throwAway($everything); }
@sethwalker $cfg['save_everything'] = '10%'; // ... snip ... if (isEnabled('save_everything'))
{ writeToDB($everything); } else { throwAway($everything); }
@sethwalker $cfg['jquery_1_11'] = 'staff'; // ... snip ... if (isEnabled("jquery_1_11"))
{ <script src="/js/lib/jquery-1.11.0.js"></script> } else { <script src="/js/lib/jquery-1.8.2.js"></script> }
@sethwalker $cfg['jquery_1_11'] = '5%'; // ... snip ... if (isEnabled("jquery_1_11"))
{ <script src="/js/lib/jquery-1.11.0.js"></script> } else { <script src="/js/lib/jquery-1.8.2.js"></script> }
@sethwalker $cfg['jquery_1_11'] = '50%'; // ... snip ... if (isEnabled("jquery_1_11"))
{ <script src="/js/lib/jquery-1.11.0.js"></script> } else { <script src="/js/lib/jquery-1.8.2.js"></script> }
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@sethwalker $cfg['jquery_1_11'] = '5%'; // ... snip ... if (isEnabled("jquery_1_11"))
{ <script src="/js/lib/jquery-1.11.0.js"></script> } else { <script src="/js/lib/jquery-1.8.2.js"></script> }
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@sethwalker $cfg['jquery_1_11'] = '50%'; // ... snip ... if (isEnabled("jquery_1_11"))
{ <script src="/js/lib/jquery-1.11.0.js"></script> } else { <script src="/js/lib/jquery-1.8.2.js"></script> }
@sethwalker $cfg['jquery_1_11'] = '100%'; // ... snip ... if (isEnabled("jquery_1_11"))
{ <script src="/js/lib/jquery-1.11.0.js"></script> } else { <script src="/js/lib/jquery-1.8.2.js"></script> }
None
@sethwalker
@sethwalker window.Etsy.Context = { // ... snip ... "feature":{ "conversations.rejuvination":true,
"activity.dynamic_load_on_scroll":true, "overlays.buttery_smooth":true, "collections.perf_render_fix":true, } };
@sethwalker if (Etsy.Context.feature["overlays.buttery_smooth"]) { doSmooth(); } else { doJanky(); }
@sethwalker TODO: Feature Flags for the asset pipeline
@sethwalker $cfg['js_debug_build'] = 'staff'; // ... snip ... if (isEnabled("js_debug_build"))
{ <script src="/js-debug/main.js"></script> } else { <script src="/js/main.js"></script> }
@sethwalker + Analytics
Continuous Experimentation
@sethwalker Small, measurable changes Dan McKinley - http://mcfunley.com/design-for-continuous-experimentation
@sethwalker Validate hypotheses
@sethwalker Invalidate hypotheses
None
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@sethwalker
None
:(
@sethwalker 100+ active flags
@sethwalker 60+ active experiments
@sethwalker 14 experimental iterations on listing page redesign
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@sethwalker N inactive experiments
@sethwalker N inactive experiments N > 0
@sethwalker Cruft
@sethwalker if (isEnabled("new_listing_page")) { <script src="/js/listing/new-listing.js"></script> } if (isEnabled("new_favorite_button")) {
<script src="/js/new-favorites.js"></script> } if (isEnabled("cart2")) { <script src="/js/add-to-cart2.js"></script> }
@sethwalker $cfg["new_listing_page"] = "100%"; $cfg["new_favorite_button"] = "5%"; $cfg["cart2"] = "50%";
@sethwalker define("foo", ["logger"], function(Logger) { Logger.warn("foo is deprecated!"); doFoo(); });
@sethwalker <link rel="stylesheet" href="/css/base.css" /> <link rel="stylesheet" href="/css/listing.css" /> if
(isEnabled("new_listing_page")) { <link rel="stylesheet" href="/css/new-listing.css" /> } if (isEnabled("new_favorite_button")) { <link rel="stylesheet" href="/css/new-favorites.css" /> } if (isEnabled("cart2")) { <link rel="stylesheet" href="/css/add-to-cart2.css" /> }
@sethwalker Let's clean up!
Fear
@sethwalker Throw away
@sethwalker Throw away ability
@sethwalker Design for Throwaway-ability Bill Scott - http://www.looksgoodworkswell.com/the-experimentation-layer/
@sethwalker Tools
@sethwalker Needs More Visibility
None
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None
@sethwalker selectorText = document.styleSheets[i].cssRules[j].selectorText; selected = document.querySelector(selectorText); results.push({ selector: selectorText,
found: !!selected ? 1 : 0}); // ... snip ... log(results);
@sethwalker Existing code - Seen in the wild = SUSPECT
@sethwalker Instrumentation
@sethwalker Increasing confidence
@sethwalker Adapting tools and process
Thanks! @sethwalker sethwalker.me/talks/continuous-experimentation