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Make your Print String nodes more useful and easier to work with in Unreal Engine. This simple trick can make debugging your Blueprints much cleaner.🔗 ─ 𝗟?...

Why kernel build time matters For developers who work on the Linux kernel, the time required to compile a clean source tree is a direct measure of productivity. Long compile cycles interrupt debugging sessions, delay testing of patches and inflate the cost of continuous integration pipelines.

You have a latitude and longitude. You pass them to a map, add a marker, and zoom in. The marker appears on another continent, in the ocean, or a few streets away from where you expected. The map may be rendering correctly. The problem is often in the coordinates you gave it—or in what you assumed those coordinates meant. Here are five checks I use when debugging a misplaced marker. ## 1. Latitude and longitude are in the wrong order A browser's Geolocation API gives you named properties: `latitude` and `longitude`. MapLibre GL JS expects an array in **longitude, latitude** order. GeoJSON uses the same order. navigator.geolocation.getCurrentPosition(({ coords }) => { const { latitude, longitude } = coords; // Wrong: [latitude, longitude] // marker.setLngLat([latitude, longitude]); // Correct: [longitude, latitude] marker.setLngLat([longitude, latitude]); }); For New York, `40.7128, -74.0060` is a familiar _latitude, longitude_ pair. A MapLibre array for that location is `[-74.0060, 40.7128]`. This bug can be hard to spot when both numbers fall within valid latitude and longitude ranges. The map may show a real location, just the wrong one. **Check:** Find the coordinate order in the documentation for every API boundary. Don't infer it from the phrase “lat/lon” in a UI label. ## 2. The numbers belong to a different coordinate reference system A pair of numbers is incomplete without its coordinate reference system (CRS). WGS84 longitude and latitude are expressed in degrees. Web Mercator coordinates, commonly associated with EPSG:3857, are expressed in projected units such as metres. If a data source gives you Web Mercator `x` and `y`, you cannot pass them to a function that expects `[longitude, latitude]` in degrees and hope the map will work it out. // Conceptual example: these are projected x/y values, // not longitude and latitude in degrees. const point = { x: -8238310, y: 4970072, crs: "EPSG:3857" }; // Wrong: marker.setLngLat([point.x, point.y]); // First transform the point to geographic longitude/latitude // using an appropriate CRS transformation library or service. The same warning applies when combining GPS data with coordinates from a local or regional map system. Label the source CRS, transform where necessary, and only then display the result. **Check:** Do you know the CRS and units of the input? Values in the millions are a strong clue that they are not ordinary longitude and latitude in degrees. ## 3. You treated a formatted coordinate as a decimal number A coordinate such as `40°42'46.08"N` is in degrees, minutes, and seconds (DMS). It represents about `40.7128°`, not `40.424608°` and not the JavaScript number `40`. For one component, the conversion is: function dmsToDecimal(degrees, minutes, seconds, hemisphere) { const value = degrees + minutes / 60 + seconds / 3600; return hemisphere === "S" || hemisphere === "W" ? -value : value; } const latitude = dmsToDecimal(40, 42, 46.08, "N"); const longitude = dmsToDecimal(74, 0, 21.6, "W"); console.log([longitude, latitude]); // [-74.006, 40.7128] The function above converts already parsed DMS parts; it is not a parser for arbitrary text. If users paste coordinates, parse the separators and hemisphere letters explicitly, then validate the result. `parseFloat("40°42'46.08\"N")` will silently return `40`, which can be especially misleading. DMS to decimal degrees is a **format conversion**. It does not transform coordinates between WGS84 and another CRS. **Check:** Inspect the raw input string and the numeric value immediately before adding the marker. ## 4. A hemisphere or minus sign was lost Latitude is positive north of the equator and negative south. Longitude is positive east of the prime meridian and negative west. If you drop the `W` from `74°W`, your marker moves from the western hemisphere to the eastern one. This often happens while cleaning form input or exporting CSV data: const input = "74.0060 W"; const longitude = parseFloat(input); // 74.006: the W is ignored A safe parser needs to apply the hemisphere sign deliberately. It should also reject contradictory inputs such as `-74 W` unless you define exactly how your app handles them. Before rendering, validate the basic ranges: function isValidLngLat(longitude, latitude) { return Number.isFinite(longitude) && Number.isFinite(latitude) && longitude >= -180 && longitude <= 180 && latitude >= -90 && latitude <= 90; } Range checks catch impossible numbers. They **cannot** reliably detect reversed coordinates when both values are plausible. **Check:** Preserve `N/S/E/W` or signed values throughout parsing, storage, and export. Test at least one western and one southern hemisphere location. ## 5. You expected an approximate location to be exact Sometimes the marker is in the right general area but not at the user's actual position. That may be a data quality issue rather than a mapping bug. Browser geolocation can use different sources, including GPS, Wi-Fi, and network information. Its result includes an `accuracy` value in metres. An IP-based location is typically an approximate area and should not be presented as an exact device position. navigator.geolocation.getCurrentPosition(({ coords }) => { marker.setLngLat([coords.longitude, coords.latitude]); console.log(`Reported accuracy: ${coords.accuracy} metres`); }); If your app falls back to IP location after permission is denied, label that fallback clearly. Zooming to street level does not make an approximate coordinate more accurate. **Check:** Show the location source and reported accuracy when available. Debug the input's precision before adjusting marker code. ## A quick debugging checklist When a marker appears in the wrong place, log the coordinate at the point where it enters the app and again just before it reaches the map: console.table({ source: "browser geolocation", // or your actual data source crs: "WGS84", longitude, latitude, valid: isValidLngLat(longitude, latitude) }); marker.setLngLat([longitude, latitude]); Then ask: 1. Does this API want `[longitude, latitude]` or `[latitude, longitude]`? 2. What CRS and units did the source use? 3. Was a DMS string parsed into decimal degrees correctly? 4. Did any minus sign or hemisphere letter disappear? 5. Is the source location approximate? If you are unsure which coordinate system your data uses, inspect a sample point before processing the full dataset. You can use CoordMap's coordinate converter to compare supported systems and check the result on a map. The most useful habit is simple: carry **order, format, CRS, and accuracy** alongside the numbers. Two coordinates alone rarely tell the whole story.

We are thrilled to announce the winners of DEV's Big Summer Bug Smash powered by Sentry! This challenge asked you to find your biggest rockstar bugs and give them an epic grand finale, and you delivered. We got real pull requests against real codebases, performance wins measured and verified, and debugging stories that had us cheering in victory. Thank you to everyone who participated. Now, let's celebrate our winners! ## 🐞 Clear the Lineup Winners The Bug That Crashes Your Import Is the Lucky One Summer Bug Smash: Clear the Lineup 🐛🛹 Sergei Parfenov Sergei Parfenov Sergei Parfenov Follow Jul 31 ## The Bug That Crashes Your Import Is the Lucky One #devchallenge #bugsmash #python #opensource 18 reactions Add Comment 6 min read 16 Redis commands. 0 spans. A hook that looked perfectly correct. Summer Bug Smash: Clear the Lineup 🐛🛹 vigneshwar vigneshwar vigneshwar Follow Aug 16 ## 16 Redis commands. 0 spans. A hook that looked perfectly correct. #devchallenge #bugsmash #opensource #go 5 reactions 1 comment 7 min read How a Missing Secret Made Agent Tool Credentials Predictable, and How We Made It Fail Closed Summer Bug Smash: Clear the Lineup 🐛🛹 NieJingChuan NieJingChuan NieJingChuan Follow Jul 20 ## How a Missing Secret Made Agent Tool Credentials Predictable, and How We Made It Fail Closed #devchallenge #bugsmash #security #opensource 3 reactions Add Comment 7 min read An 80-second browser freeze in Zulip's Manage channels, fixed by killing quadratic DOM work Summer Bug Smash: Clear the Lineup 🐛🛹 Pentine Pejay Pentine Pejay Pentine Pejay Follow Aug 21 ## An 80-second browser freeze in Zulip's Manage channels, fixed by killing quadratic DOM work #devchallenge #bugsmash 10 reactions Add Comment 5 min read Fixing a Mobile Click-Through Bug Caused by Unmounting a React Portal on PointerDown Summer Bug Smash: Clear the Lineup 🐛🛹 MartinDelophy MartinDelophy MartinDelophy Follow Jul 21 ## Fixing a Mobile Click-Through Bug Caused by Unmounting a React Portal on PointerDown #devchallenge #bugsmash #react #javascript 1 reaction Add Comment 4 min read ## 🪲 Smash Stories Winners Why did my benchmark stop at N=22? A debugging story in nine bugs Summer Bug Smash: Smash Stories Submission 🐛🛹 xbill xbill xbill Follow for Google Developer Experts Jul 15 ## Why did my benchmark stop at N=22? A debugging story in nine bugs #bugsmash #debugging #ai #python 13 reactions 6 comments 4 min read Ctrl+S said "Saved." The file was 0 bytes. Summer Bug Smash: Smash Stories 🐛🛹 Christo Christo Christo Follow Jul 26 ## Ctrl+S said "Saved." The file was 0 bytes. #devchallenge #bugsmash #cpp #qt 2 reactions Add Comment 6 min read Rise and fall of a self-fixing agent Summer Bug Smash: Smash Stories 🐛🛹 Aliaksei Zelianouski Aliaksei Zelianouski Aliaksei Zelianouski Follow Aug 16 ## Rise and fall of a self-fixing agent #devchallenge #bugsmash #agents #ai 13 reactions 5 comments 12 min read The SSE Fragmentation Catastrophe That Took Down CareerPilot AI Summer Bug Smash: Smash Stories Submission 🐛🛹 Aashita Aashita Aashita Follow Jul 15 ## The SSE Fragmentation Catastrophe That Took Down CareerPilot AI #devchallenge #bugsmash 12 reactions 4 comments 6 min read Gemini returned 429 at 2.3% of its documented quota. My retry loop ran for 4 days. Summer Bug Smash: Smash Stories 🐛🛹 Sergey Inozemtsev Sergey Inozemtsev Sergey Inozemtsev Follow Jul 17 ## Gemini returned 429 at 2.3% of its documented quota. My retry loop ran for 4 days. #bugsmash #devchallenge #googlecloud #gemini Add Comment 6 min read ## 🛹 Best Use of Sentry Winners The bug report was wrong, and that was the interesting part Summer Bug Smash: Clear the Lineup 🐛🛹 Germán Massello Germán Massello Germán Massello Follow Aug 22 ## The bug report was wrong, and that was the interesting part #devchallenge #bugsmash 5 reactions Add Comment 8 min read Sentry's trace said gemini-flash-latest. Google served gemini-3.6-flash. Summer Bug Smash: Clear the Lineup 🐛🛹 Asuran Asuran Asuran Follow Aug 11 ## Sentry's trace said gemini-flash-latest. Google served gemini-3.6-flash. #devchallenge #bugsmash #python #ai 5 reactions Add Comment 9 min read Python can't weakref a ValueError. Sentry's deduplication found out the expensive way. Summer Bug Smash: Clear the Lineup 🐛🛹 JonathanSolvesProblems JonathanSolvesProblems JonathanSolvesProblems Follow Aug 19 ## Python can't weakref a ValueError. Sentry's deduplication found out the expensive way. #devchallenge #bugsmash #python #debugging 3 reactions Add Comment 12 min read ## ✨ Best Use of Google AI Winners Smashing a silent connection leak in node-postgres (pg-pool) Summer Bug Smash: Clear the Lineup 🐛🛹 Malbolged Malbolged Malbolged Follow Jul 17 ## Smashing a silent connection leak in node-postgres (pg-pool) #bugsmash #node #postgres #opensource 2 comments 7 min read Two AI debuggers found the same bug. Both stopped one function short. Summer Bug Smash: Clear the Lineup 🐛🛹 Hassan Imam Hassan Imam Hassan Imam Follow Aug 22 ## Two AI debuggers found the same bug. Both stopped one function short. #devchallenge #bugsmash #python #opensource 1 reaction Add Comment 9 min read Six silent bugs in a voice AI phone line Summer Bug Smash: Clear the Lineup 🐛🛹 Dhruv Dhruv Dhruv Follow Aug 21 ## Six silent bugs in a voice AI phone line #devchallenge #bugsmash Add Comment 12 min read When Batching Your AI Agents Makes Them Read Each Other's Mail Summer Bug Smash: Clear the Lineup 🐛🛹 Yuva Kunaal Yuva Kunaal Yuva Kunaal Follow Jul 16 ## When Batching Your AI Agents Makes Them Read Each Other's Mail #devchallenge #bugsmash #ai #opensource 6 reactions Add Comment 7 min read Zulip logged 'Successfully processed.' Your reply was already gone. Summer Bug Smash: Clear the Lineup 🐛🛹 Uptime Architect Uptime Architect Uptime Architect Follow Aug 1 ## Zulip logged 'Successfully processed.' Your reply was already gone. #devchallenge #bugsmash #python #opensource Add Comment 8 min read ## 🐛 Runner-Ups I Used Sentry to Expose a Silent Data-Loss Bug with Zero Errors Summer Bug Smash: Clear the Lineup 🐛🛹 Mir Shah Mir Shah Mir Shah Follow Aug 15 ## I Used Sentry to Expose a Silent Data-Loss Bug with Zero Errors #devchallenge #bugsmash #ai #development 4 reactions 1 comment 9 min read Fix: A Missing .catch() That Crashes Your Entire Node.js Process (ethers.js WebSocket Provider) Summer Bug Smash: Clear the Lineup 🐛🛹 Ethan Park Ethan Park Ethan Park Follow Aug 21 ## Fix: A Missing .catch() That Crashes Your Entire Node.js Process (ethers.js WebSocket Provider) #devchallenge #bugsmash 4 reactions Add Comment 3 min read The smolagents bug that made my agent retry the same valid code three times Summer Bug Smash: Clear the Lineup 🐛🛹 Himanshu Kumar Himanshu Kumar Himanshu Kumar Follow Jul 20 ## The smolagents bug that made my agent retry the same valid code three times #devchallenge #bugsmash #python #ai 19 reactions 25 comments 4 min read Fixing a null-body crash in the Formbricks survey SDK, found by Sentry Summer Bug Smash: Clear the Lineup 🐛🛹 Lewis Sawe Lewis Sawe Lewis Sawe Follow Aug 21 ## Fixing a null-body crash in the Formbricks survey SDK, found by Sentry #devchallenge #bugsmash 11 reactions 3 comments 7 min read Our SDK Cached One User's Answer and Served It to the Next One Who Asked Summer Bug Smash: Clear the Lineup 🐛🛹 Talha Anwar Talha Anwar Talha Anwar Follow Aug 11 ## Our SDK Cached One User's Answer and Served It to the Next One Who Asked #bugsmash #devchallenge #devops #ai Add Comment 7 min read ## Prizes All winners will receive a cash prize, a DEV++ Membership, and an exclusive DEV badge. Our three Best Use of Sentry winners will also receive a limited edition Sentry skateboard. All participants with a valid submission will receive a completion badge on their DEV profile. ## What's Next? We've got two other challenges running right now. Join today! Join the Kaggle Benchmarking Challenge: $2,500 in Prizes for FIVE Winners! Open-ended scope for custom model testing Jem Jem Jem Follow for The DEV Team Sep 23 ## Join the Kaggle Benchmarking Challenge: $2,500 in Prizes for FIVE Winners! #devchallenge #kagglebenchmarkchallenge #machinelearning #ai 105 reactions 9 comments 4 min read Join the Sanity Challenge: $2,500 in prizes for FIVE winners! Jem Jem Jem Follow for The DEV Team Sep 18 ## Join the Sanity Challenge: $2,500 in prizes for FIVE winners! #sanitychallenge #devchallenge #agents #webdev 206 reactions 38 comments 8 min read Thanks again to all who participated. This one was really fun. Happy coding 🐛🛹

Swift 6.4 is here, and it's a game-changer for cross-platform dev. Swift Build is now the default engine for SwiftPM, unifying the experience across macOS, Linux, and Windows. Plus: SBOM support and l

AI is here, and here to stay. Elbit Systems Israel has been introducing it into the development life cycle, where I personally use it for researching, coding, debugging and bouncing ideas off of. Tha...

Ladybird’s August 2026 update brings Twitch playback, in-engine DevTools, layout caching, and more Rust code as the browser edges closer to its alpha.