# fifo Published articles for fifo. This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles. ## The Label as Contract: Consent and Priority as the Whole Queue DevFeed: [The Label as Contract: Consent and Priority as the Whole Queue]() Original publisher: [Read original article]() Author: Philipp Lehmann (philipp.lehmann@gruppe.ai) Published: 2026-07-28T07:00:00Z Content type: tutorial Language: en Sources: [Philipp Lehmann]() Topics: [issue tracker](), [audit trail](), [coding]() Tags: [agents](), [audit-trail](), [consent](), [fifo](), [issue-tracker](), [priority](), [security]() ### AI overview The article argues that an autonomous coding agent should act only on issues carrying a specific human-applied label. Free-form issue content is unauthenticated and cannot establish consent or priority; label actions provide an independent audit trail, and priority should be derived from label transitions. ### Source excerpt agent-ready label as the only consent gate for a coding agent: FIFO order by label time and a re-read-then-swap claim so two runs never share an issue. ## Replacing AWS Step Functions with SQS FIFO queues and cutting the cost in half DevFeed: [Replacing AWS Step Functions with SQS FIFO queues and cutting the cost in half]() Original publisher: [Read original article]() Author: Alexei Liulin Published: 2025-03-14T14:47:27Z Content type: article Language: en Sources: [Homegate Engineering Blog - Medium]() Topics: [Amazon Simple Queue Service (SQS)](), [AWS Step Functions](), [Amazon Web Services]() Tags: [aws](), [aws-step-functions](), [batching](), [cloud-computing](), [cost](), [cost-optimization](), [email](), [fifo](), [lambda](), [notifications](), [push-notifications](), [queue](), [sqs](), [sqs-queue](), [workflow]() ### AI overview The article describes SMG Real Estate's Search Alerts system, which batches property-match notifications for delivery by email or mobile push notification. It explains the original AWS Step Functions implementation and its transition-cost problem, motivating a more cost-efficient approach using SQS FIFO queues. ### Source excerpt One of the core services for SMG Real Estate is Search Alerts -- a service that allows users to be notified about new properties published on ImmoScout24 and Homegate. For example, if a user is looking for a new apartment having N rooms and costing less than X, and not finding any matches now, they can create a search alert with those search criteria. When a new property matching those criteria is published, the user will be notified either via email or a mobile push notification. About the Search Alerts system Users can choose the frequency of notifications -- either every 5 minutes or every 4 hours (assuming there are any to be delivered). The vast majority of search alerts are configured with the 5-minute frequency. Just to get an idea of the scale, we have: Millions of published properties match saved search alerts every day More than a million emails and push notifications sent daily Check out our "Homegate's fast and modern search experience helps users find their dream home" blog post for an overview of how Search Alerts work. The Original Implementation In the original implementation we used an AWS Step Function to achieve the 5- minute batching of notifications: When a new property matching a search alert arrived, the StartSendNotificationProcess lambda would start a Step Function execution specific to that search alert. All it did was waiting for 5 minutes while the matches accumulated in the matches-{searchAlertId} SQS queue, which was programmatically created for that specific search alert If more matching listings arrived during the 5-minute waiting period, the StartSendNotificationProcess lambda attempted to start the step function execution with the same name. When it failed with the ExecutionAlreadyExists error, we knew there was already a SF for waiting. That way the deduplication of notification processes was guaranteed. After 5 minutes of waiting time, the Step Function execution proceeded with triggering the LoadMatches lambda that received the acc ## Building Reliable Messaging Patterns in AWS with SQS and SNS DevFeed: [Building Reliable Messaging Patterns in AWS with SQS and SNS]() Original publisher: [Read original article]() Author: Guillermo Ojeda Published: 2024-12-20T15:20:38Z Content type: tutorial Language: en Sources: [Guille Ojeda]() Topics: [Amazon Simple Queue Service (SQS)](), [Amazon Web Services](), [Messaging](), [distributed-systems]() Tags: [architecture](), [aws](), [distributed-system](), [distributed-systems](), [error-handling](), [fifo](), [messaging](), [scale](), [sns](), [sqs](), [technical]() ### AI overview This tutorial explains how to build reliable distributed messaging systems with AWS SQS and SNS. It covers queue configuration, error handling, scaling patterns, message retention, long polling, visibility timeouts, and the differences between Standard and FIFO queues, using Node.js examples. ### Source excerpt Building distributed systems requires putting a lot of attention on communication between components. These components often need to exchange information asynchronously, and that's where message queues and pub/sub systems are the go-to solution. AWS ... ## 11 Data Structures Every Developer Should Know DevFeed: [11 Data Structures Every Developer Should Know]() Original publisher: [Read original article]() Author: Nelson Djalo Published: 2024-10-24T16:06:22Z Content type: tutorial Language: en Sources: [Amigoscode Newsletter]() Topics: [Data structures](), [Programming](), [Algorithms]() Tags: [arrays](), [data-structures](), [developer](), [fifo](), [graph](), [programming](), [queue]() ### AI overview A tutorial introducing 11 data structures relevant to software development, coding interviews, algorithm efficiency, and system design. It explains arrays, 2D arrays, queues, stacks, and graphs, including their properties and practical use cases. ### Source excerpt Master These 11 Data Structures to Excel in Programming and System Design ## AWS FIFO Queues with Message Groups for Atomic Processing at Scale DevFeed: [AWS FIFO Queues with Message Groups for Atomic Processing at Scale]() Original publisher: [Read original article]() Author: Nick De Cooman Published: 2022-03-03T09:55:58Z Content type: tutorial Language: en Sources: [Homegate Engineering Blog - Medium]() Topics: [Amazon Simple Queue Service (SQS)](), [Amazon Web Services](), [Serverless](), [event driven](), [Scalability](), [Publish-subscribe pattern]() Tags: [architecture](), [aws](), [decoupling](), [distributed](), [event](), [event-driven](), [events](), [fifo](), [serverless](), [sns](), [sqs]() ### AI overview A tutorial on using AWS FIFO queues and message groups to process events for multiple objects in parallel while ensuring that only one instance processes events for the same object at a time. It presents a serverless architecture using SNS, SQS, and Lambda for atomic listing ingestion. ### Source excerpt How to process multiple objects in parallel with the guarantee that for each unique object, only a single instance is processed simultaneously In a distributed, event-driven architecture, many challenges arise when processing large sets of data. One of them is the need for scalability when handling event streams with a substantial throughput. The challenge becomes even more complicated when processing these events involves atomic operations. In this case, we cannot simply process multiple events in parallel. As an example, let's say that we are building a service that ingests listings into our platform. The ingestion process involves several steps and requires multiple API operations. As a result, the whole ingestion can take up to several seconds per listing to complete. Now, here is where it gets tricky: a constraint of our service is that, while we are processing a listing, we cannot process other events for the same listing. The ingestion should be considered an atomic operation, and hence, only a single execution per listing can be performed simultaneously. At Homegate, we run most of our infrastructure on AWS in a serverless fashion. At the core of this, Lambda functions execute application logic. A common pattern is to use SNS topics to fan-out messages, and SQS for acting as a decoupling buffer between an SNS topic and some Lambda function. For our ingester service, a logical architecture could look like this: Listing events are published to a dedicated SNS topic. An SQS queue subscribes to this topic and consumes the events. Here, the events are buffered until a Lambda instance removes them from the queue and processes the corresponding listing. Under normal circumstances -- in which the processing would not involve an atomic operation -- this architecture would be a good fit. It would scale automatically relative to the number of Lambda instances that consume events from the queue, without much additional configuration. However, in the case where we cannot p ## Queueing theory for fun and practice #2: нагрузка и время отклика DevFeed: [Queueing theory for fun and practice #2: нагрузка и время отклика]() Original publisher: [Read original article]() Author: Ruslan Cheremin (noreply@blogger.com) Published: 2020-07-27T15:13:00Z Content type: tutorial Language: ru Sources: [\>рабочие заметки]() Topics: [queueing theory]() Tags: [fifo](), [queueing-theory](), [random](), [tag-e5017782b67f](), [theory]() ### AI overview This article explains how system load affects response time through internal queues and buffers. It discusses the characteristic J-curve, the difficulty of deriving a general analytical formula, and how queueing discipline, workload distributions, server allocation, and utilization influence waiting time. ### Source excerpt Во храме Божьей Матери Поклонской батюшка Иннокентий принимает исповедь у раба божьего обыкновенно минут за 10, а утешения жаждут около 5-и рабов божьих в час. Много ли стульев надобно поставить во храме, дабы исповеди ожидающие не толпились в праздности пред святым алтарем? "Массовое окормление паствы: пособие для начинающих" (редакция 3-я, неизданная) (Часть 2, начало: ТМО, square