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This is a submission for DEV's Summer Bug Smash: Smash Stories powered by Sentry . This is our official submission for the DEV Big Summer Bug Smash challenge under the #bugsmash track. Below is the technical tale of how we isolated, debugged, and optimized cross-layer node latency issues when deploying our Web3 framework on Polygon. The Problem: The Post-Hard Fork RPC Latency Wall 🐛 During heavy network volume spikes or directly following major ledger upgrades, our automated event listener logging pipeline kept crashing with random, non-deterministic invalid block range exceptions when attempting to pull historical data blocks via standard eth_getLogs routines. The Technical Root Cause The root bottleneck came down to an internal desync inside shared public RPC telemetry environments: The Bor Layer mints new block headers at a blistering speed (~2 seconds). The Internal Indexer DB takes slightly longer to completely unpack, parse, and commit transaction event logs to disk. When our asynchronous scripts called the node, latest grabbed the bleeding edge tip of the chain from memory, but a simultaneous getLogs query hit the slower indexer database. This split-millisecond race condition threw immediate pipeline errors. The Fix: Layered Application Buffering 🛠️ To smash this bug without modifying low-level node client builds, we engineered a programmatic block-padding delay loop directly into our interaction routers. Instead of tracking unfinalized tip block states blindly, we forced our queries to target safe block ranges sitting securely just behind the tip of the chain. // Localized block-buffer deployment fix const currentChainTip = await provider . getBlockNumber (); const indexedBlockBoundary = currentChainTip - 3 ; // Buffer 3 blocks (~6 second safety zone) const targetLogs = await contract . getLogs ({ fromBlock : indexedBlockBoundary - 20 , toBlock : indexedBlockBoundary }); This structural adjustment completely stabilized our off-chain reward data pipeline, gua

This is a submission for DEV's Summer Bug Smash: Smash Stories powered by Sentry . I spent a week deploying a CrewAI agent to AWS Bedrock AgentCore. The SDK wasn't on PyPI. The error messages were 200 OKs. The container crashed without logs. And the naming regex rejected hyphens without telling me why. This is the full debugging trail. Every failure was silent. Every fix required reading source code nobody documented. Table of Contents The Project Failure 1: The SDK That Doesn't Exist on PyPI Failure 2: The 200 OK That Means Failure Failure 3: The Container That Crashed With No Logs Failure 4: The Naming Regex Nobody Documented The Two-Client Split Nobody Mentions What I Learned The project I built a resume-tailoring AI agent with CrewAI and Amazon Bedrock. It takes a job description, analyzes your resume, identifies gaps, and rewrites bullet points to match what the role actually needs. Locally it worked perfectly. CrewAI orchestrates the agents, Bedrock Nova Pro handles the LLM calls, and the output is solid. Deploying it to production was the problem. AWS launched Bedrock AgentCore in June 2026 as a managed runtime for AI agents. You containerize your agent, push the image, and AgentCore handles scaling, memory, and invocation. Sounds simple. It was not simple. Failure 1: The SDK that doesn't exist on PyPI The docs say to install bedrock-agentcore-client . I ran: pip install bedrock-agentcore-client It installed successfully. No errors. That's because there's a placeholder package on PyPI with that name. It installs, imports fail silently, and your container builds successfully with a broken dependency inside. The real SDK lives in AWS's CodeArtifact registry. You need to configure pip to pull from a private index: aws codeartifact login --tool pip \ --domain amazon-agent-runtimes \ --repository agent-runtimes-pypi \ --domain-owner 600427722194 Then install from there. The PyPI package is a trap. Nobody warns you. Hours lost: 3. The error only appears at runtime

This is a submission for DEV's Summer Bug Smash: Smash Stories powered by Sentry . 🎭 The Recurring Villain If you've built WordPress sites long enough, you know this bug. It doesn't show up as an error in your console. It doesn't throw a fatal exception. It just quietly sits there, page after page, client after client — and it's called video bloat . Nine years into web development, I lost count of how many times a client sent me a site with a message like "it's just... slow." And nine times out of ten, when I opened DevTools and checked the waterfall, the story was the same: three, four, sometimes ten embedded YouTube videos, each one dragging in its own iframe, its own set of scripts, its own chunk of megabytes — all loading the second the page rendered, whether the visitor scrolled past them or not. One video embed alone can pull in 500KB–1MB+ before a user even presses play. Multiply that by a landing page stacked with testimonials, product demos, and a hero video, and you've got a page that fights your Core Web Vitals before it's even finished loading. 🔁 The Manual Fix (Every. Single. Time.) For years, my solution was the same tedious ritual: Find every video embed on the page. Replace the iframe with a static thumbnail image. Write a bit of custom JavaScript to swap the thumbnail for the real embed on click or scroll. Repeat it for YouTube. Repeat it again for Vimeo, because Vimeo's oEmbed API works differently. Repeat it again for self-hosted <video> tags, because now you're dealing with <source> tags instead of iframes. Test it across whatever page builder the client was using — Elementor, Divi, WPBakery, or straight-up Gutenberg blocks — because every one of them nests the video markup slightly differently. It worked. But it was never reusable. Every project meant writing the lazy-load script again, half from memory, half copy-pasted from my own old projects, tweaked just enough to fit the new theme's markup. It was the same bug, wearing a different site's c

Two critical security flaws in WordPress’ software have given hackers the chance to remotely take over tens of millions of websites, according to an estimate by a cybersecurity researcher.

This is a submission for DEV's Summer Bug Smash: Clear the Lineup powered by Sentry . Project Overview Formbricks is an open-source survey and experience management platform built with Next.js, TypeScript, React, and Tailwind CSS. It lets teams create and deploy surveys across websites, apps, and email. Developers can self-host it or use the cloud version. With over 12,000 GitHub stars and hundreds of contributors, it is one of the most actively maintained open source alternatives to Qualtrics. Bug Fix or Performance Improvement Formbricks supports custom regex validation rules on survey questions. A survey creator can set a pattern that user responses must match before they are accepted. The problem was in how that pattern was stored. The validation schema for regex pattern rules only checked that the input was a non-empty string: // Before the fix export const ZValidationRuleParamsPattern = z . object ({ pattern : z . string (). min ( 1 ), flags : z . string (). optional (), }); z.string().min(1) means "give me any string with at least one character." It does not verify that the string is actually a valid regular expression. So a survey creator could type [invalid as their pattern, the schema would accept it, it would be saved to the database, and then when a real user submitted a response, the system would try to run new RegExp("[invalid") , JavaScript would throw a SyntaxError , and the survey would crash silently at runtime. The bug never surfaced during setup. It only appeared when a real user was trying to submit a real response. Code Pull Request: github.com/Tobore005/formbricks/pull/1 Here is the fix: const isValidRegexPattern = ( pattern : string ): boolean => { try { new RegExp ( pattern ); return true ; } catch { return false ; } }; const isValidRegexFlags = ( flags : string | undefined ): boolean => { if ( flags === undefined ) return true ; try { new RegExp ( "" , flags ); return true ; } catch { return false ; } }; export const ZValidationRuleParamsPa

This is a submission for DEV's Summer Bug Smash: Clear the Lineup , powered by Sentry . Project Overview I built LeakLens Control Room to keep AI away from the financial math. Python calculates every dollar. The optional model explains the evidence. A human decides whether to act. LeakLens is a live, functional restaurant margin-review application built with Python, SQLite, HTML, CSS, and JavaScript. It uses synthetic data in the public demo. The optional application narrative provider defaults to GPT-5.6, but every rate, threshold, ranking, and dollar scenario comes from deterministic code. Then a date string proved that deterministic code can still lie. I had let a raw CSV field decide which operating day counted as "current." Bug Fix or Performance Improvement The symptom LeakLens groups channel metrics by date, sorts those dates, and analyzes the last one against prior days. That works when every input is canonical ISO data such as 2026-07-09 . The loader only checked that the date field was not blank. This input slipped through: metrics = [ DailyMetric ( " 2026-7-9 " , " direct " , 500 , 250 , 0 , 0 , 125 ), DailyMetric ( " 2026-07-10 " , " direct " , 1000 , 50 , 0 , 0 , 250 ), ] July 10 is later than July 9. Python's string ordering sees something else: sorted ([ " 2026-07-10 " , " 2026-7-9 " ]) # ['2026-07-10', '2026-7-9'] LeakLens selected the final string, 2026-7-9 , as the current day. That mistake spread through the report: expected current date: 2026-07-10 actual current date: 2026-7-9 actual gross sales: 500.00 sales-loss scenario: 500.00 discount scenario: 225.00 The input had not shown a current sales collapse or discount leak. The analyzer compared the days backward and produced $725 of false scenario impact from synthetic data. For a restaurant operator, this is worse than a visible crash. A crash asks for attention. A plausible financial report can send someone to audit the wrong promotion, question the wrong manager, or change a schedule that was

This is a submission for DEV's Summer Bug Smash: Smash Stories powered by Sentry . There is a version of this story where I walk you through the technical challenges in a clean, detached voice. Structured. Professional. Composed. This is not that version. Seven months. A hundred pages of documentation written alongside the code, not after it. A live system serving rural clinics in Delta State, Nigeria. And three bugs so specific and so cruel that each one felt designed to find the exact gap between what I thought I knew and what I actually knew. The Delta Health Information and Appointment Booking System was my final year project at the University of Port Harcourt. That sentence makes it sound smaller than it was. This was a real system for real clinics, serving patients who travel for hours to reach a healthcare facility only to find the clinic is full, the doctor is not in, or nobody told them their appointment was cancelled. These are not hypothetical users. These are people whose access to healthcare depends on whether the software works. That is a different kind of pressure than getting a good grade. And it did not start at deployment. Before a single line of code was written, I had to pitch the entire concept to my university supervisor, the Head of Department, the Faculty Dean, and an external examiner. The system had to be defensible not just technically but practically. It had to demonstrate that it solved a real problem that real people in Delta State were actually facing. I was presenting to people with decades of experience who would ask questions I had not thought of yet. That kind of scrutiny either sharpens you or breaks you. I chose to let it sharpen me. The stack was React.js, Node.js, PHP with Laravel, MySQL, AWS, and Docker. Communication channels included SMS gateways, WhatsApp Business API, and USSD because not every patient in rural Delta State has a smartphone. The system had to run on 2G connections, on entry-level Android phones with 2GB RAM

This is a submission for DEV's Summer Bug Smash: Smash Stories powered by Sentry . Copilot started whispering random letters into my ear, like it was leaking secret tokens from the underworld! Cute, but also, a bug! This sounds like a classic data serialization or sanitization failure in the text-to-speech (TTS) pipeline. What is happening here is a classic disconnect between the UI layer (what you see on screen) and the data payload sent to the background engine. When you read a response on screen, the Android app renders clean Markdown or HTML. However, when you tap "Read Aloud," the app has to strip away all background formatting, structural code, and system metadata, converting the response into a raw, clean string of text before handing it off to the mobile TTS engine. In this case, the background script running the relay is failing to sanitize that data stream. It is accidentally passing raw control characters, escape sequences, or hidden system tracking tokens (like structural delimiters or character-encoding artifacts) directly into the text pipeline. Because the mobile TTS engine doesn't understand that these symbols are meant to be ignored structural code, it tries to do exactly what it’s programmed to do: it reads them literally. When the voice engine encounters unexpected symbols, raw strings of characters, or broken text boundaries in the middle of a sentence, it completely disrupts the engine's predictive text processing: ● Pitch and Speed Fluctuations: Mobile TTS engines use deep learning models to predict natural tone, cadence, and inflection based on context. Injecting random, non-linguistic characters completely derails the engine's context window, causing it to panic-adjust its pitch, speed, and emphasis mid-sentence. ● Mispronunciations: The hidden characters slice words in half semantically, forcing the engine to mispronounce standard words because it's trying to blend them with the rogue data trailing right behind them. Here is a direct, high-s

This is a submission for DEV's Summer Bug Smash: Clear the Lineup . Project Overview Formbricks is an open-source survey and experience-management platform. Its packages/surveys package ships the client-side survey runner, and inside it, packages/surveys/src/lib/logic.ts is the module that decides, for every question and every "skip logic" / branching rule a survey author configures, whether a given condition ( equals , doesNotEqual , contains , isEmpty , and friends) is true for a respondent's answer. This is pure, unglamorous logic — but it's load-bearing: it's what routes respondents through the correct sequence of questions. I picked up issue #8527 for the "Clear the Lineup" track, which reports that doesNotEqual conditions weren't behaving correctly for single-choice questions. Bug Fix or Performance Improvement The doesNotEqual operator is supposed to be the exact logical negation of equals . For most answer shapes it was. But for MultipleChoiceSingle answers, the survey runtime sometimes represents the selected value as a single-element array rather than a bare string (this happens via getLeftOperandValue , e.g. when a choice answer is merged with an "other" option path). To handle that shape, both equals and doesNotEqual had a special-case clause that unwraps a one-element array and compares its only entry to the right-hand value. equals 's fallback: return ( ( Array . isArray ( leftValue ) && leftValue . length === 1 && typeof rightValue === " string " && leftValue . includes ( rightValue )) || leftValue === rightValue ); doesNotEqual 's fallback (before the fix): return ( ( Array . isArray ( leftValue ) && leftValue . length === 1 && typeof rightValue === " string " && ! leftValue . includes ( rightValue )) || leftValue !== rightValue ); At a glance this looks like a faithful "negate every sub-expression" mirror of equals . It isn't. The array-includes clause was correctly inverted ( !leftValue.includes(rightValue) ), but the second disjunct, leftValue !==

This is a submission for DEV's Summer Bug Smash: Clear the Lineup . Project Overview Typst is the Rust-based markup typesetting system that's been quietly eating LaTeX's lunch for the last couple of years — you write plain-text markup, Typst compiles it to PDF (or HTML) with a real incremental compiler underneath instead of a multi-pass macro soup. Part of what makes it pleasant is that it exposes its own evaluator to itself: a document can call #eval("some typst code") and get back whatever that code produces, at runtime, inside the document being compiled. It's a small feature, but it opens up a surprisingly deep rabbit hole, which is exactly where this bug was hiding. Bug Fix or Performance Improvement The problem: typst/typst#8632 reports that Typst crashes instead of erroring when #eval is used to recursively re-import the file it's running in. The repro is one line. Save this as overflow.typ : #eval("import \"overflow.typ\"") Then: $ ./target/debug/typst compile overflow.typ overflow.pdf thread 'main' (750833) has overflowed its stack fatal runtime error: stack overflow, aborting No PDF, no diagnostic, no exit code you can act on — just a native stack overflow and a SIGABRT. Typst has had cyclic-import detection since forever; a normal top-level import "overflow.typ" inside itself gets caught cleanly with an error: cyclic import message. Something about routing the import through #eval specifically was bypassing that check. The hunt I'll be upfront about how this investigation actually went: I worked through it with Claude (Anthropic's coding agent) rather than solo. The triage pass it did before I sat down with the code had already narrowed the search to one function — eval_string in crates/typst-eval/src/lib.rs — and named the suspect line. That's a big head start, but a named suspect isn't a confirmed root cause, so the actual work was reading that function next to its sibling, the file-level eval() a few lines above it, and checking the claim against the s

An error with the cloud computing giant’s billing operation caused some customers’ monthly bills to rise from a few cents to billions of dollars.

Update: This investigation spawned a complete stress-testing toolkit. See the apktool-diagnostics repo for the full tool with security scanning, round-trip validation, and fuzzing setup. The Setup I was deep into a project stress-testing apktool — the standard tool for decompiling and rebuilding Android APKs — hunting for real bugs to fix, not hypothetical ones. While digging through recent issues and advisories, I ran across a patched vulnerability: CVE-2026-39973 , a path traversal bug that let a malicious resources.arsc make apktool write decoded files outside the intended output directory. Already fixed upstream. Advisory published. Case closed, according to everyone else. I didn't believe it until I broke it myself. Why "already patched" wasn't good enough Advisories describe what should happen. They don't prove it. And a tool like apktool has one job that matters more than any other: you point it at a file you don't trust — someone else's APK — and it processes that file on your machine. If the sanitization it depends on for that trust boundary can silently regress in a refactor (which is exactly what happened here — a PR reorganizing resource-file-path construction dropped the call to BrutIO.detectPossibleDirectoryTraversal() without anyone noticing), then "patched now" only tells you about today. It doesn't tell you the mechanism actually holds, and it doesn't tell you what "vulnerable" concretely looks like on your own machine, with your own files. So instead of writing "confirmed CVE-2026-39973, see upstream fix" and moving on, I decided to reproduce it myself, end to end. Building both sides of the fence Step one: build apktool twice from source — once at v3.0.1 (the last vulnerable tag), once at current HEAD (post-fix). Now I had a vulnerable binary and a patched binary sitting side by side, and no more reason to trust anyone's summary of what the difference actually did. Step two: I needed a malicious input. The vulnerability lived in how ResFileDecoder

Submission for DEV's Summer Bug Smash — Smash Stories track. There was a file in my repo called run_benchmark_1_22.py . Not 1 to 24, which is what the harness was written to do. Not 1 to 26, which is how many Mersenne exponents the agents know. Twenty-two. A chart in the README — a2a_latency_times_1_22.png — agreed. At some point, past-me had decided the benchmark ends at 22, committed the evidence, and moved on. This summer, hunting for a Bug Smash target, I finally asked: why 22? The setup a2a-benchmark compares A2A agent performance across four languages. Python and Go sit behind Gemini tool-calling (ADK); Node and Rust are bare HTTP handlers. Each computes Mersenne primes with Lucas–Lehmer; a harness sweeps N from 1 to 24 and draws two charts. I ran the full sweep. At N=24, the Python column printed N/A . Every other language returned data. There it was — not a decision, a crash , worked around by shortening the run until it stopped hurting. The 4,300-digit wall The Python agent's response at N=24 wasn't even subtle about it: "Exceeds the limit (4300 digits) for integer string conversion; use sys.set_int_max_str_digits() to increase the limit" CPython 3.11 added a default cap on int→str conversion — 4,300 digits — as a denial-of-service mitigation. My agent stringified every prime it found. The 24th Mersenne prime, 2^19937−1, has 6,002 digits . Here's the part that made me laugh out loud: the stringified list was never returned . The tool reports only its elapsed time. The line that had silently amputated my benchmark at N=23 was decorative. The fix was git rm energy: delete the str() , keep the raw int. Go had the identical dead weight ( val.String() ) inside its timed region — it just happened not to crash. One deleted expression, and a column of data that had never existed came into being: N=24, Python, 2,425.9 ms. It gets worse before it gets better With the agents finally running, I kept pulling the thread. The harness parsed Python's elapsed time out of th

Submission for DEV's Summer Bug Smash — Clear the Lineup track. The codebase a2a-benchmark is my multi-language A2A (Agent-to-Agent) performance suite: four agents — Python and Go behind Gemini tool-calling via ADK, Node.js and Rust as direct handlers — each compute Mersenne primes with the Lucas–Lehmer test, while a harness sweeps N=1–24 and charts calculation time and round-trip time. The committed results stopped at N=22. I never questioned that. I should have. The headline bug: a whole column of data didn't exist CPython 3.11+ limits int→str conversion to 4,300 digits by default (a DoS mitigation). My Python agent stringified each prime it found: mersenne_primes . append ( str (( 1 << p ) - 1 )) The 24th Mersenne exponent is p=19937, and 2^19937−1 has 6,002 digits . So for any request of 24+ primes, the tool raised ValueError — and the A2A response dutifully delivered the stack-trace text instead of a result: "text": "Exceeds the limit (4300 digits) for integer string conversion; use sys.set_int_max_str_digits() to increase the limit" The benchmark's Python column was structurally incapable of producing data at N≥24. The kicker: the stringified list was never used . The tool returns only elapsed_time . The fix is deleting the str() — which also removes formatting work from the timed region that the Node and Rust agents never paid (Go had the same dead val.String() call). Fix: PR #1 — plus a switch from time.time() (wall clock, non-monotonic) to time.perf_counter() , and a regression test at count=24. Before/after, N=24 row: Node.js Rust Go Python before 1633.01 ms 812.57 ms 1451.49 ms N/A (crash) after 1616.13 ms 824.10 ms 1531.10 ms 2425.9 ms The harness was reading its data from LLM prose The Python agent's timing came back in two places: a structured elapsed_time in the tool artifact, and the model's prose. The harness regexed the prose first : m = re . search ( r " It took ([\d\.\-e]+) seconds " , text ) In live runs, Gemini said "Calculating the first 5 Mer

This is a submission for DEV's Summer Bug Smash: Smash Stories powered by Sentry . It was 11:14 PM. My friend DM'd me on Twitter: "Your app just hung for 30 seconds, spun indefinitely, and then completely died." I opened the browser DevTools console pointed at production and saw it — the screen flooded in red: GET https://careerpilot-ai.run.app/api/analyze-career net::ERR_INCOMPLETE_CHUNKED_ENCODING 200 (OK) The Server-Sent Events stream powering CareerPilot AI was systematically collapsing on Google Cloud Run. And I had no idea why. Locally on localhost:3000 , the agentic pipeline was a masterpiece. The multi-stage reasoning logs streamed gracefully — Step 1 flowed into Step 6, the final structured JSON payload arrived within seconds, the UI lit up with a complete personalized career roadmap. Beautiful. But once deployed behind Google's Front End (GFE) proxy, the pipeline was a graveyard of broken sockets. The Architecture Under Fire CareerPilot AI runs a six-stage agentic pipeline on every career analysis request. Instead of firing a single long-running prompt to Gemini and making the user stare at a blank screen for 20+ seconds, we designed a Server-Sent Events logging stream to broadcast real-time reasoning steps directly to the browser — giving the interface the feel of a live, active mentor thinking out loud. Once the final stage (Self-Evaluation & Constraint Validation) completed, the backend constructed a massive, nested 15KB JSON payload containing the personalized roadmap: skill weightings, role benchmarks, resource links, and a 30-day milestone calendar. Here was the delivery mechanism — and the landmine hiding inside it: // server.ts — The vulnerable streaming channel app . get ( " /api/analyze-career " , async ( req , res ) => { res . setHeader ( " Content-Type " , " text/event-stream " ); res . setHeader ( " Cache-Control " , " no-cache " ); res . setHeader ( " Connection " , " keep-alive " ); // Stream intermediate reasoning logs per step for ( let st

I found a slow, insidious memory leak in a Node.js API gateway caused by lingering event listeners; I fixed it by scoping emitters per request, enforcing cleanup in finally blocks, and adding leak‑aware tests and runtime safeguards—memory usage flattened and OOM restarts stopped. The Incident The gateway handled TLS termination, auth, and request fan‑out for many microservices. Over weeks its resident set size climbed in a staircase pattern until Kubernetes began OOM‑killing pods under load. The failure was gradual —light traffic ran for days, peak traffic crashed in hours—so it escaped casual monitoring. Investigation Heap snapshots and allocation profiles showed growing counts of small objects —closures, request metadata, and event listeners—rather than one giant allocation. Tracing revealed an internal event bus where request‑scoped listeners were attached but not always removed: an early‑exit authentication path returned before the cleanup function ran, leaving listeners that held references to request state. The GC saw those objects as live and never reclaimed them. The Fix (technical details) 1. Scoped emitters per request. Replace global emitters for request‑local concerns with a short‑lived EventEmitter created at request start. When the request ends, the emitter goes out of scope and the whole closure graph becomes collectible. 2. Guaranteed teardown via try/finally . Wrap the entire request pipeline so cleanup runs on success, error, or early return; the finally detaches any remaining listeners, clears timers, and releases caches. 3. Leak‑aware CI tests and runtime metrics. A harness simulated thousands of requests across code paths, captured heap snapshots, and asserted bounded object counts. Production metrics tracked listener counts and emitted alerts when thresholds were exceeded. 4. Operational safeguards. Added backpressure on accept queues, a soft memory threshold that disabled nonessential tracing, and rollout halting on excessive crash loops. Thes

OpenAI found two unrelated bugs masquerading as one in ChatGPT's data infrastructure. Silent hardware corruption on one Azure host and an 18-year-old race condition in GNU libunwind's setcontext function with a one-instruction vulnerability window. The breakthrough came from switching to population-level crash analysis rather than examining individual core dumps. By Steef-Jan Wiggers

We’re excited to announce our first ever Summer Bug Smash! Every app has its share of rockstar bugs....

Cloudflare has recently shared how they uncovered an issue in their Rust implementation of CUBIC, a congestion controller algorithm, which prevented it from recovering from a scenario of heavy packet loss at the start of a connection. By Gianmarco Nalin