Build browser games that actually work.
Fifty independently authored, actionable implementation field notes. Each page has a distinct engineering question, implementation approach, worked scenario, failure mode, acceptance test, and primary-source links. These are applied guides, not peer-reviewed original research or claimed benchmark results.
Original new playable game
Prism Relay — 150 solvable laser puzzles
Rotate mirrors to route light across a 7×7 circuit. Includes undo, hints, keyboard and mobile controls, deterministic puzzles and locally saved stage progress.
Play Prism Relay free →Performance — 10 field guides
FIELD GUIDE 01Prioritize the actual largest image in a game launcherPerformance · source-backedFIELD GUIDE 02Fix slow taps in a large game navigation menuPerformance · source-backedFIELD GUIDE 03Stop product card shifts while game covers loadPerformance · source-backedFIELD GUIDE 04Investigate stutter using frame-time percentilesPerformance · source-backedFIELD GUIDE 05Cache static background layers in Canvas gamesPerformance · source-backedFIELD GUIDE 06Cap rendering resolution on high-density phonesPerformance · source-backedFIELD GUIDE 07Budget decoded image memory, not only network transferPerformance · source-backedFIELD GUIDE 08Keep scoreboards stable while fonts downloadPerformance · source-backedFIELD GUIDE 09Limit nonessential script evaluation at game startupPerformance · source-backedFIELD GUIDE 10Make performance verification reproduciblePerformance · source-backed
Images — 10 field guides
FIELD GUIDE 11Deliver responsive game art with accurate srcset and sizesImages · source-backedFIELD GUIDE 12Make mobile game banners readable without losing the subjectImages · source-backedFIELD GUIDE 13Verify browser-produced WebP files using the container signatureImages · source-backedFIELD GUIDE 14Compare AVIF, WebP and PNG based on perceptual qualityImages · source-backedFIELD GUIDE 15Write meaningful alternative text for game cover linksImages · source-backedFIELD GUIDE 16Reduce unintended disclosure when exporting customer-supplied photosImages · source-backedFIELD GUIDE 17Reserve space before images finish loadingImages · source-backedFIELD GUIDE 18Choose sprite atlases using memory and draw-call evidenceImages · source-backedFIELD GUIDE 19Use motion only when a preview benefits the playerImages · source-backedFIELD GUIDE 20Separate verified file savings from subjective visual qualityImages · source-backed
Input — 10 field guides
FIELD GUIDE 21Keep touch drags working beyond a puzzle board edgeInput · source-backedFIELD GUIDE 22Make every essential puzzle action reachable by keyboardInput · source-backedFIELD GUIDE 23Offer a two-tap alternative to complex draggingInput · source-backedFIELD GUIDE 24Return keyboard focus predictably after closing a menuInput · source-backedFIELD GUIDE 25Design reachable action buttons for narrow mobile screensInput · source-backedFIELD GUIDE 26Freeze game time when the browser becomes hiddenInput · source-backedFIELD GUIDE 27Use stable simulation steps across different refresh ratesInput · source-backedFIELD GUIDE 28Measure action responsiveness independently of display refreshInput · source-backedFIELD GUIDE 29Distinguish intentional card taps from touch scrollingInput · source-backedFIELD GUIDE 30Give one clear response for each shield or undo actionInput · source-backed
Accessibility — 10 field guides
FIELD GUIDE 31Check text contrast on animated neon backgroundsAccessibility · source-backedFIELD GUIDE 32Respect reduced motion without hiding essential informationAccessibility · source-backedFIELD GUIDE 33Announce meaningful game milestones without a speech floodAccessibility · source-backedFIELD GUIDE 34Expose canvas puzzle controls through semantic buttonsAccessibility · source-backedFIELD GUIDE 35Describe image conversion validation failures preciselyAccessibility · source-backedFIELD GUIDE 36Keep focus on the same puzzle tile after each moveAccessibility · source-backedFIELD GUIDE 37Require user choice before playing game audioAccessibility · source-backedFIELD GUIDE 38Keep settings and instructions accessible at 200 percent zoomAccessibility · source-backedFIELD GUIDE 39Detect hidden keyboard traps in pause overlaysAccessibility · source-backedFIELD GUIDE 40Make safe items and hazards distinguishable without color visionAccessibility · source-backed
Security — 10 field guides
FIELD GUIDE 41Reject near-matching level codes before they enter a gameSecurity · source-backedFIELD GUIDE 42Reject renamed HTML files masquerading as image uploadsSecurity · source-backedFIELD GUIDE 43Introduce strict Content Security Policy without breaking paid storefrontsSecurity · source-backedFIELD GUIDE 44Render user-supplied player names as text, never executable markupSecurity · source-backedFIELD GUIDE 45Distinguish local progress convenience from real purchase entitlementSecurity · source-backedFIELD GUIDE 46Avoid partial customer-facing releases during bulk uploadsSecurity · source-backedFIELD GUIDE 47Prevent old deployment rollback from overwriting new improvementsSecurity · source-backedFIELD GUIDE 48Prove a publicly served game matches its release manifestSecurity · source-backedFIELD GUIDE 49Prevent mixed HTML and JavaScript versions after a site updateSecurity · source-backedFIELD GUIDE 50Keep free play previews separate from purchase authorizationSecurity · source-backed