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The First Microcontroller Was the TI TMS1000 (1974)
Ask most people to name the chip that started modern electronics and they will say the microprocessor. But there is a quieter hero inside almost everything you own that beeps, blinks, or connects to the internet: the microcontroller. And the first one you could actually buy shipped in 1974 as the Texas Instruments TMS1000. Microprocessor vs. microcontroller The distinction matters. A microprocessor, like Intel's famous 4004, is just the processing core. To build anything useful with it you still have to wire up separate memory chips, input/output controllers, and support logic on a circuit board. A microcontroller collapses all of that onto a single piece of silicon: the CPU, the ROM that holds your program, the RAM that holds your data, and the I/O pins that talk to the outside world, all in one package. That is exactly what the TMS1000 did. Designed by Texas Instruments engineers Gary Boone and Michael Cochran, it was a 4-bit device using a Harvard architecture, meaning it kept program memory and data memory in separate spaces so it could fetch an instruction and read data at the same time. One chip in, one chip out, and you had a complete tiny computer dedicated to a single job. Cheap enough to put in everything The genius of the TMS1000 was not raw power, it was economics. In 1974 you could buy the chips in volume for around two dollars each. By 1979, Texas Instruments was selling roughly 26 million of them every year. That price point changed what engineers could build. Suddenly it made sense to drop a small, programmable brain into products that never would have justified a full computer. You have almost certainly held one. The TMS1000 family ran the Speak & Spell, the Big Trak programmable toy vehicle, and the electronic memory game Simon, along with countless calculators, microwave ovens, and appliances. Each one was doing the same fundamental thing an IoT node does today: read some inputs, run a fixed program, drive some outputs. Why this still matters for
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I built a browser CAD where you type a sentence and walk through the house
Concept design for a building is slow and expensive. A homeowner planning an extension, or a contractor trying to win a job, is stuck between two bad options: pay a drafter $500–2,000 for a concept package, or fight SketchUp's learning curve for a week. Meanwhile the actual idea — "a 4-bed duplex with a garage and a palm out front" — fits in one sentence. So I built Forge3D Spaces : you type that sentence, and a few seconds later you're walking through a furnished 3D house in your browser — with measured floor plans, DXF for AutoCAD, and a cost estimate that come out of the same model. No install. Here's how it works under the hood. The pipeline: sentence → structured plan → building The naive approach — "ask an LLM to emit a 3D scene" — falls apart fast. Models are bad at spatial consistency; walls don't meet, rooms overlap, doors float. So the LLM never touches geometry directly. It emits a structured program , and a deterministic solver turns that into a watertight building. The prompt becomes a spec. A strict JSON-schema call (OpenRouter, json_schema response format with every field required) turns "4-bed duplex with a garage" into a room program: room types, target areas, adjacencies, storeys. A slicing-tree solver lays it out. This is the old floorplanning trick from chip design — recursively split a rectangle with horizontal/vertical cuts until every room has its area. A squarify pass keeps rooms from collapsing into corridors. The output is exact rectangles with real dimensions, guaranteed non-overlapping and gap-free. Walls, openings, roof, furniture get generated from the solved plan. Every door and window is placed by rule, not by vibes. Because the plan is a real data structure, the 2D floor plan, the 3D model, the elevations, and the bill of quantities are all views of the same thing . Drag a wall and they all move together. Nothing drifts out of sync, because there's nothing to sync — it's one model. The rendering: WebGPU, and the fallback you actually
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Lorde says Ray-Ban Meta AI glasses are ‘not sexy’
Lorde was performing at the Real Cool Festival in Madrid on Thursday and took some time during her set to speak out against AI glasses. While she didn't specify any brands in particular, it's likely she was taking a shot at festival sponsor Ray-Ban, which has collaborated with Meta on a pair of AI smartglasses. […]
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Pentagon releases new batch of UFO files, China's Tianwen-2 reaches its asteroid target, and more science stories
Catch up on the most interesting science news from the last week.
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Shall We Go On Sinning So That Grace May Increase? is hypnotic, healing, and hopeful
Matmos are an incredibly accomplished duo between their own solo records like the masterpiece A Chance to Cut Is a Chance to Cure and production classic Bjork records like Vespertine. But Drew Daniel, one half of Matmos, is fiendishly prolific. When he's not literally dreaming up new viral music genres, he's also putting out records […]
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Building a Three.js 3D Product Configurator for WooCommerce: 4 Things I Didn't Expect
Most WooCommerce product pages still show the same thing stores have shown for 20 years: a handful of flat photos. I spent the last few months building Noorifa, a plugin that replaces that with an interactive Three.js viewer — customers rotate the model, zoom in, and switch colors/materials on specific meshes in real time, synced to the store's actual WooCommerce variations. The 3D rendering part was the easy 20%. The other 80% was a series of small, specific problems that don't show up in a Three.js tutorial. Here are four of them. 1. A directional light rig can't light a face it can't see Early on, customers rotating a table model would find the underside of the tabletop rendering near-black — no matter how far I pushed the light intensity. The rig at the time was a single key light plus a hemisphere ambient: scene . add ( new THREE . HemisphereLight ( 0xffffff , 0x444444 , 1.2 ) ); const keyLight = new THREE . DirectionalLight ( 0xffffff , 1.2 ); keyLight . position . set ( 3 , 5 , 4 ); scene . add ( keyLight ); The bug was geometric, not a brightness problem: keyLight sits above the model, so its light direction only reaches surfaces whose normal faces back toward it. A downward-facing surface — the underside of an overhanging tabletop — can't receive any direct contribution from a light positioned above it, at any intensity. Cranking the brightness slider was scaling a number that was multiplying against zero. The fix was closer to actual three-point studio lighting: key, fill, and rim from above for shape and separation, plus a dedicated light from below, and a brighter hemisphere ground color to approximate bounced light: scene.add( new THREE.HemisphereLight( 0xffffff, 0x888888, 1.1 * brightness ) ); const keyLight = new THREE.DirectionalLight( 0xffffff, 1.1 * brightness ); keyLight.position.set( 3, 5, 4 ); const fillLight = new THREE.DirectionalLight( 0xffffff, 0.5 * brightness ); fillLight.position.set( -4, 2, 3 ); const rimLight = new THREE.DirectionalLigh
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Be the right Platform Team
Throughout my career I have had to work with quite a few platform teams, and I was part of two for a couple of years. Some were bad, some were good and some should not have existed at all. I want to tell you my user experience, what I have seen work and what not and what you should definitely avoid doing. Be The Multiplier This is the main goal of a platform team. As a team, it needs to be a multiplier. If the platform team supports 10 teams, then each work it commits should multiply by 10. If the team member builds a new feature, it should be helpful for all the other teams. Otherwise, the platform team is an addition, and in most cases it is then better to split the platform team and add them to all other teams, instead of being a separate team. Because the amount of communication needed is in most cases quadratic in relation to the number of teams. Reducing Cognitive Load The platform should take away cognitive load for all the teams it supports. By doing so, they will have more time to implement business requirements. Let's say a platform team provides Gitlab runners or Azure Agents where people can run their CI/CD code on. They should not need to know how the runners are scaled, or how the agents are updated. This takes away the need for that skill set in all the teams. Build a Community A platform team has a unique position. It is building something that all other developers probably can build as well. Some could do it even better than the platform team itself. For some platform teams, their ego sometimes comes in to play or just straight up refuses their help because they are not the team. But it is not the job of the platform team to build a product, but a platform where everyone can thrive and/or build on. So onboard the community on the platform! The Law of Diffusion applies to almost all companies. You will have the innovators that want to build it themselves and the early adopters that will voice their opinion, but will not build it themselves. Those two
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Claude Code Sends 33k Tokens Before Your Prompt; OpenCode Sends 7k
A new side-by-side measurement shows Claude Code ships roughly 33,000 tokens of system prompt, tool schemas, and scaffolding before your prompt even arrives — about 4.7x the ~7,000 tokens OpenCode sends on the same setup. The bigger cost surprise is next: Claude Code re-wrote up to 54x more prompt-cache tokens per session, and cache writes bill at a premium. How the test was run The benchmark (published by Systima) spliced a logging proxy between each harness and the model endpoint, capturing the exact request payload and the API's usage block. Both harnesses were pinned to the same conditions: Claude Code 2.1.207 and OpenCode 1.17.18 , both pointed at claude-sonnet-4-5 Fresh config directories, empty workspace, no MCP servers, no instruction files, permissions bypassed Tasks ranged from "reply with OK" (isolating fixed overhead) to a write-run-test-fix loop against FizzBuzz A zero-tools variant separated system-prompt weight from tool-schema weight The payload captures are exact; the only adjustment was subtracting a constant ~6,200-token gateway envelope that wrapped every request in the test setup. The fixed floor Harness Fixed overhead before your prompt Cache-write behavior Claude Code 2.1.207 ~33,000 tokens Re-wrote tens of thousands of cache tokens per run; up to 54x OpenCode OpenCode 1.17.18 ~7,000 tokens Byte-identical prefix each run; cached once, read back cheaply OpenCode's request prefix was byte-identical in every captured run, so it paid to cache its payload once per session and read it back for pennies. Claude Code re-wrote large amounts of prompt-cache tokens mid-session, run after run — and because cache writes bill at a premium, one usage dashboard climbs while the other stays flat. Where it piles on in real setups The harness floor is only the start. The benchmark added variables one at a time: A production repository's 72KB instruction file added an average of ~20,000 tokens to every request. Five modest MCP servers added 5,000–7,000 more. By th
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I scanned 15 public Lovable apps. 40% load their database in the browser.
No hacking — a passive scan only looks at what your browser already downloads when it opens a page. Here's what I found: 6 of 15 load their Supabase database directly client-side. The public API key sits in the page source. That's fine if Row-Level Security is configured right — but it's one wrong setting away from "anyone can read the whole table." 14 of 15 ship no Content-Security-Policy — a simple, high-value hardening against script injection, almost always missing. Is this theoretical? No. Two apps I audited with the owner's permission: A social app: the profiles table — user names, cities, and a password hash — readable by a logged-out stranger. Closed in an afternoon. A paid learning app: 155 paid study sheets and 4,872 answers were readable by anyone, with no account and no subscription — its entire paid catalogue, a single API call away. The paywall lived only in the front-end; the database served everything to everyone. Loading Supabase in the browser isn't the mistake. Not enforcing access in the database (RLS) is. And the tools you build with won't tell you — they'll happily ship it. If you built something on Lovable / Bolt / Replit with real users (or paying ones), it's worth 60 seconds to check what a stranger can already see. I made a free tool that runs the surface check (passive, no signup): sealdy.dev Happy to answer questions on how RLS leaks happen and how to lock them down.
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The Developer's Guide to Picking the Right Coding LLM at Scale
The Developer's Guide to Picking the Right Coding LLM at Scale Six months ago, I was staring at our monthly AI bill — $14,000 and climbing fast. We were using the "premium" model for everything, including trivial code completions. That night, I built a small internal benchmark to figure out which models actually earn their cost. What I learned reshaped how we think about AI tooling, vendor lock-in, and what "production-ready" really means. Here's the raw truth from my testing rig, what we shipped, and how we cut costs by 70% without touching output quality. Why I Stopped Trusting Default Recommendations Every vendor says their model is the best. Every benchmark site ranks things differently. Most "best of" lists are either sponsored or built on vibes. I needed numbers that matched my actual workflow: generating Python services, debugging JavaScript race conditions, implementing TypeScript algorithms, and reviewing Go for security. So I took ten models, threw identical prompts at them, and scored them myself. No vendor PR. No cherry-picked examples. Just the same five tasks, run the same way, scored on the same rubric. Here are the ten models I tested, with their output pricing per million tokens — because at scale, that's the metric that decides whether your AI strategy is viable or a margin killer. Model Provider Output $/M DeepSeek V4 Flash DeepSeek $0.25 DeepSeek Coder DeepSeek $0.25 Qwen3-Coder-30B Qwen $0.35 DeepSeek V4 Pro DeepSeek $0.78 DeepSeek-R1 DeepSeek $2.50 Kimi K2.5 Moonshot $3.00 GLM-5 Zhipu $1.92 Qwen3-32B Qwen $0.28 Hunyuan-Turbo Tencent $0.57 Ga-Standard GA Routing $0.20 Before you ask: yes, I tested against the originals. I also tested against Global API's unified routing layer, which lets you hit any of these through one endpoint. More on that later — it became the architectural decision that actually saved us. My Benchmark Methodology (No Marketing Fluff) I built five tasks that mirror what my engineers actually do every week. Not synthetic acad
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Power BI DAX Essential Functions — Explained with Examples
If you’ve ever struggled with CALCULATE() or wondered why SUMX() behaves differently from SUM() , this guide is for you. DAX (Data Analysis Expressions) is the language that powers Power BI , Analysis Services , and Power Pivot — enabling dynamic calculations, filtering, and time intelligence. Below is a categorized cheat sheet of essential DAX functions , plus examples showing how to use each in real-world Power BI scenarios. Filtering & Context These functions control how filters are applied and evaluated in your calculations. Function Example Description CALCULATE() CALCULATE(SUM(Sales[Amount]), Region[Name] = "Nairobi") Changes filter context to calculate total sales for Nairobi. FILTER() FILTER(Sales, Sales[Amount] > 10000) Returns a table filtered by condition. ALL() CALCULATE(SUM(Sales[Amount]), ALL(Region)) Ignores filters on Region. REMOVEFILTERS() CALCULATE(SUM(Sales[Amount]), REMOVEFILTERS(Region)) Removes filters from Region. VALUES() VALUES(Customer[City]) Returns unique list of cities. SELECTEDVALUE() SELECTEDVALUE(Product[Category], "All") Returns selected category or “All” if none. TREATAS() TREATAS(VALUES(Temp[City]), Customer[City]) Applies one table’s values as filters on another. KEEPFILTERS() CALCULATE(SUM(Sales[Amount]), KEEPFILTERS(Product[Category] = "Electronics")) Keeps existing filters and adds new ones. ALLSELECTED() CALCULATE(SUM(Sales[Amount]), ALLSELECTED(Region)) Respects user selections in visuals. ALLEXCEPT() CALCULATE(SUM(Sales[Amount]), ALLEXCEPT(Sales, Sales[Year])) Removes all filters except Year. Aggregation Summarize or aggregate data across rows or columns. Function Example Description SUM() SUM(Sales[Amount]) Adds all sales amounts. AVERAGE() AVERAGE(Sales[Amount]) Calculates mean value. COUNT() COUNT(Customer[ID]) Counts non-blank entries. COUNTROWS() COUNTROWS(Sales) Counts rows in a table. DISTINCTCOUNT() DISTINCTCOUNT(Customer[ID]) Counts unique customers. MIN() MIN(Sales[Amount]) Finds smallest sale. MAX() MAX(Sales[Amo
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Feels Great To be part of this project, its a awesome experince to build this project and completed it on time
We Taught a Snowflake Warehouse to Judge World Cup Conviction and Write the Verdict Back to Solana Soumyadeep Dey Soumyadeep Dey Soumyadeep Dey Follow Jul 12 We Taught a Snowflake Warehouse to Judge World Cup Conviction and Write the Verdict Back to Solana # devchallenge # weekendchallenge # snowflake 5 reactions 1 comment 16 min read
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EEM 101: On-Box Automation That Runs Even When Your NMS Doesn't
This is Part 1 of a 5-part series on Cisco EEM. We start here with the fundamentals and a few working applets, then build toward self-healing networks, automated diagnostics, compliance guardrails, and a complete real-world deployment. Ask ten network engineers what they use EEM for, and nine will say the same thing: "Oh, I have an applet that auto-recovers err-disabled ports." Then they never touch it again. That's a shame, because Embedded Event Manager is one of the most capable tools already sitting inside every Cisco IOS device you own — and almost nobody uses more than 1% of it. It's a full automation engine that lives on the box . No external server. No API gateway. No orchestration platform. Just the router or switch, watching itself, ready to react the instant something happens — even if the WAN is cut, the NMS is down, and it's three in the morning. This series is about using that other 99%. By the end you'll have a toolkit of applets you can deploy and, more importantly, a way of thinking about on-box automation. But we start at the foundation: what EEM actually is, how it's put together, and why "on the box" is a bigger deal than it sounds. What EEM actually is Embedded Event Manager is an event-driven automation framework built into Cisco IOS, IOS-XE, and NX-OS. Strip away the jargon and it's a very simple idea: When something happens, do something about it — automatically, on the device itself. That "something happens" is an event . That "do something" is one or more actions . Bundle an event with its actions and you have an applet — the basic unit of EEM. That's the whole model. The power comes from how many different things can be an event , and how much an action can do. Events EEM can watch for include: A syslog message matching a pattern (an interface flapping, an HSRP state change, a config being saved). An SNMP OID crossing a threshold (CPU over 85%, a power supply going absent, temperature rising). A CLI command being entered (someone typing wr
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Building a secure OS: the hard list — what I found and what I'm fixing in IONA OS
Every operating system has security gaps. Most never publish them. I am publishing mine. IONA OS is a sovereign operating system written from scratch in Rust. It has a kernel, a GUI, a blockchain protocol, a programming language, and a 140,000‑line AI running in Ring 0. It is designed to be secure by default. But secure is a journey, not a destination. Here is the hard list — the security issues I found in IONA OS, and what I am doing about them. 1. The filesystem is not encrypted at rest IONAFS reads and writes sectors in plain text directly to the disk. I already have a real ChaCha20‑Poly1305 engine with per‑file key derivation ( fs/encrypted_storage.rs ), but it is only used for backup/distribution — not for everyday local reading and writing ( fs/ionafs/mod.rs ). Why this matters: For a journalist or a civil servant, this is the central threat scenario: a lost device, confiscation at a border, or seizure. What I'm doing about it: Integrating encrypted_storage.rs into the normal IONAFS read/write path. Every write will be encrypted automatically. The key will be derived from a PIN or TPM. 2. Deleting a file does not destroy it delete_file() removes only the index entry. The data sectors remain on the disk, recoverable with standard forensic tools. Why this matters: For users with high security requirements — journalists, activists, government officials — this is a critical gap. What I'm doing about it: Adding a shred() function that overwrites the data sectors with random patterns before releasing them, with a configurable number of passes. 3. The keystore uses XOR, not real encryption security/keystore.rs pretends to use AES/ChaCha in its comments, but the actual implementation is a simple XOR stream — trivial to break once an attacker has access to the disk. Why this matters: This is a critical vulnerability. XOR is not encryption. If an attacker has access to the disk, they can recover the keys. What I'm doing about it: Replacing the XOR stream with real ChaCh
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How I Built a GeoGuessr Game for Super Mario Odyssey
I wanted to build something different from the usual fan project. Instead of recreating gameplay, I asked a different question: How well do players actually remember the worlds of Super Mario Odyssey? The result is OdysseyGuessr, a browser game inspired by GeoGuessr. Players receive a screenshot from one of the game's Kingdoms and must place a marker on the correct location. Every meter counts. The project includes: Browser-based gameplay Single-player with customizable rounds Real-time multiplayer with a 5,000 HP battle system Community-submitted locations Admin moderation tools One of the biggest challenges wasn't the gameplay—it was collecting interesting locations that were difficult but still fair. Watching players confidently choose the wrong cliff or rooftop has been surprisingly entertaining. If you're interested in browser games or Nintendo fan projects, I'd love to hear your feedback. Play here: https://odyssey-guessr.lovable.app OdysseyGuessr is an unofficial fan project and is not affiliated with Nintendo.
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The One DevOps Metric Every Solo Developer Ignores
What’s up everyone! Back again for my daily drop. We talk a lot about deployment frequency and lead time for changes, but if you're a solo dev or part of a small team building something like LaunchAlly , there’s one metric that rules them all: Time to Recovery (TTR) from a bad push. When you're marketing, coding, and handling support all at once, a broken main branch is a massive bottleneck. Here is my quick tip for today: Invest 20 minutes into setting up strict automated rollbacks . If a deployment fails health checks, let the system revert it instantly without your intervention. Spend lots of hours working today...happy to go to bed now:) What’s your go-to strategy for handling failed deployments on the fly?
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TechCrunch Mobility: A robotaxi ultimatum
Welcome back to TechCrunch Mobility, your hub for the future of transportation and now, more than ever, how AI is playing a part.
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Passion Edition
Submission: Edu-Insight Assistant What I build I built the Edu-Insight Assistant, a tool designed for educators to bridge the gap between complex school management data and actionable insights. It allows teachers to query students performance data using natural language, turning educational evaluation into a conversation rather than a manual data-processing task. Demo 🔗 Link: Passion-challenge How I Built It I utilized Next.js for a responsive, performant frontend and hooked it up to Google Gemini 3.5 API. The core logic involves a server-side API route that takes a teacher's natural language questions, prompt Gemini to generate the necessary SQL, and execute that query against a database. This architecture makes data exploration accessible to non-technical educators. Prize Categories: - Best Use of Google AI : Leveraged Gemini 3.5 Flash for natural language-to-SQL translation and result interpretation. - Best Use of Snowflake: Designed with an extensible data layer ready for production-scale analytical workloads in Snowflake.
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I built my first Robinhood Chain app as an index basket
I built a small index basket app on Robinhood Chain because I wanted to understand the developer path from the first contract deploy all the way to a working frontend. The app is intentionally plain: a user deposits Stock Tokens, which are blockchain tokens that represent real equity exposure, and receives an ERC-20 basket share. ERC-20 is Ethereum's standard token interface, so a compatible token exposes familiar methods like balanceOf , transfer , and approve . The basket share is priced from live price feeds, and the user can redeem it back into the underlying Stock Tokens. That's the part that made this interesting to me. The chain is custom, but the app path is not. I still wrote Solidity, deployed with Foundry, read contract state with viem, and wrote transactions from React with wagmi. If you've built normal web apps, think of the chain's RPC endpoint as the API base URL. A wallet is login plus a signing key. A smart contract is backend code you deploy to the chain, except you should treat it like immutable infrastructure because you don't get to hot-patch it casually later. The demo and source are here: App: https://robinhood-chain-dapp.vercel.app/ Code: https://github.com/hummusonrails/robinhood-chain-dapp-example The custom chain still feels like the EVM Robinhood Chain is a custom Arbitrum Chain, which means it runs as a dedicated chain on the stack of Arbitrum, an Ethereum scaling system. It is also EVM-compatible. EVM means Ethereum Virtual Machine, the runtime that executes Solidity contracts, so the tooling surface looks like the Ethereum developer flow many tutorials already teach. An L2, or rollup, is a chain that executes transactions separately and then posts compressed proof or transaction data back to Ethereum. Robinhood Chain uses Ethereum blobs for data availability, which is a cheaper Ethereum data lane for rollups to publish the data needed to reconstruct chain state. Gas, the metered compute fee you pay to run transactions, is paid in ETH.
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skip에서 partition overwrite로: business_date 재처리를 Iceberg로 다시 표현하기
skip에서 partition overwrite로: business_date 재처리를 Iceberg로 다시 표현하기 이전 글에서는 같은 source_hash 가 다시 들어왔을 때 기존 successful run을 재사용하는 idempotency를 다뤘다. 하지만 재처리에는 두 종류가 있다. 1. 같은 입력이 다시 들어온 경우 -> skip이 맞다. 2. 같은 business_date의 정정 입력이 들어온 경우 -> skip하면 안 된다. -> 같은 날짜의 gold 결과를 중복 없이 교체해야 한다. manufacturing-data-platform-mini 의 B5 slice는 두 번째 문제를 아주 작게 다룬다. 전체 Spark pipeline을 만든 것이 아니다. gold_daily_metrics Iceberg table 하나를 local Spark에서 만들고, business_date partition overwrite와 snapshot evidence만 검증했다. Scenario 이미 아래 gold row가 있다. business_date=2026-06-29 plant-a / line-1 / gearbox-a units_produced=120 defect_count=3 나중에 같은 business_date=2026-06-29 에 대한 정정 source가 들어온다. 운영자가 원하는 것은 append가 아니다. 원하지 않는 상태: 2026-06-29 old row 2026-06-29 corrected row -> 같은 날짜 결과가 중복됨 원하는 상태: 2026-06-29 corrected row만 남음 2026-06-30 같은 다른 날짜 partition은 그대로 유지됨 재처리 전후 snapshot evidence가 남음 그래서 이 slice의 질문은 이렇다. 같은 business_date의 정정 source를 처리할 때, gold table에서 해당 날짜 partition만 중복 없이 교체하고, 어떤 run이 어떤 Iceberg snapshot을 만들었는지 남길 수 있는가? Decision Pressure Slice1의 CSV pipeline은 already-successful source를 안전하게 skip할 수 있다. dataset_id + business_date + source_hash 이 key가 같으면 같은 입력이다. 다시 계산해도 같은 결과이므로 기존 run을 재사용한다. 하지만 source_hash 가 달라졌다면 의미가 다르다. same business_date different source_hash 이건 retry가 아니라 correction이다. CSV run-folder 방식에서는 새 run output을 만들 수는 있지만, "현재 gold table에서 해당 날짜를 원자적으로 교체한다"는 table-level 의미가 약하다. Iceberg를 붙이는 이유는 여기 있다. source_hash -> 같은 입력인지 판단하는 idempotency key business_date partition -> 정정 시 교체할 gold table 범위 snapshot_id -> table commit의 evidence 즉 Spark/Iceberg는 도구 이름을 추가하려고 붙인 것이 아니라, 재처리 상태 전이를 더 명확히 표현하기 위해 붙였다. Options Option 장점 문제 판단 same source면 항상 재계산 단순함 retry 때 불필요한 commit이 계속 생김 제외 corrected source를 append 구현 쉬움 같은 날짜 gold row가 중복될 수 있음 제외 whole-table overwrite 단순함 다른 날짜 partition까지 지울 위험 제외 business_date partition overwrite correction 범위가 명확함 Spark/Iceberg 설정과 test가 필요 선택 MERGE/upsert 강력함 이번 skeleton에 과함 backlog 이번 구현은 DataFrameWriterV2.overwritePartitions() 를 사용했다. corrected_d