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275 questions, 991 terms and 600 topics in 30 areas.
59 results for “Deployment Strategies”
Blue-Green Database Schema
The constraint that makes fast rollback actually work — both application versions must be able to run against one schema at the same time.
Rolling Update Surge
The extra capacity a rolling deployment temporarily adds, and the unavailability it is permitted, which together decide whether the rollout is safe under load.
Blue-Green Deployment
Running two identical production environments and switching traffic from the old one to the new one in a single cut, with the old kept warm for rollback.
Deployment Pipeline
The automated path from commit to production, structured so that each stage increases confidence and the whole is fast enough to be run on every change.
Deployment Topology View
A diagram showing where software actually runs — regions, zones, networks and hosts — which is where availability and cost properties become visible.
Etsy's Continuous Deployment
Etsy moved from infrequent, risky releases to dozens of deploys a day, demonstrating that deployment frequency and stability improve together rather than trading off.
Join Strategies
The three ways a database combines two row sets — nested loop, hash join and merge join — and the conditions under which each is correct.
Artifact Signing
Cryptographically signing build outputs so that deployment can verify what is being run was produced by the expected pipeline from the expected source.
Automated Release Verification
A gate that compares the new version's live signals against the old one's and decides, on stated criteria, whether to continue or revert.
Blast Radius Reduction
The set of deliberate partitions — accounts, regions, zones, cells, tenants, deployment stages — that bound how far any single failure or compromise can reach.
Bloom Filter Cache Guard
Placing a Bloom filter in front of an expensive lookup so that keys which certainly do not exist never reach it.
Build Attestation
A signed statement about how an artifact was produced — by which builder from which source — that a deployment gate can verify rather than trust.
CI/CD
Merging work continuously into a shared trunk with automated verification, and keeping every commit in a state that could be released.
Canary Release
Routing a small fraction of traffic to a new version, watching its metrics, and expanding or rolling back based on what they show.
DORA Metrics
Four measures of software delivery performance — deployment frequency, lead time for change, change failure rate, and time to restore service.
Dual Write
Writing the same change to both the old and new stores during a migration, and the reconciliation that makes it trustworthy.
Expand-Contract Migration
Changing a schema in additive steps that keep old and new code both working, so deployment and migration never have to be simultaneous.
Feature Flag
A runtime switch that decouples deploying code from releasing behaviour, so unfinished or risky work can ship dark.
Image Registry
The store from which container images are pulled, and an under-appreciated availability and security dependency of every deployment and every autoscale event.
Immutable Backup
A backup that cannot be modified or deleted for a defined retention period, even by an administrator — the control that makes backups survive ransomware and insider error.
Microservices
An architectural style where an application is a set of independently deployable services, each owning its data and aligned to a business capability.
Monolith vs Microservices
A trade of deployment independence against distributed-systems complexity, decided by team topology far more often than by technology.
Point-in-Time Recovery
Restoring a database to any moment within a retention window by replaying transaction logs onto a base backup, rather than only to a snapshot boundary.
Prompt Registry
A versioned store of production prompts with their model bindings, parameters and evaluation results, so a prompt change is a reviewable, traceable, reversible deployment.
Prompt Regression Suite
A set of test cases with expected properties, run against a prompt on every change, to detect quality regressions before deployment.
Prompt Versioning
Treating prompts as versioned, reviewed, tested artefacts rather than as strings edited in place.
Reconciliation Loop
A controller that continuously compares declared state with actual state and acts to close the gap, replacing deployment as an event with convergence as a property.
Render Location Decision
Where HTML is produced — build time, server, edge or browser — chosen per route by how personalised and how cacheable that route is.
Restore Drill
A scheduled, timed exercise of restoring from backup into a clean environment — the only thing that converts a backup from a hope into a control.
Six Rs of Migration
The standard menu of options for each application in a migration — rehost, replatform, refactor, repurchase, retire, retain.
Testing Strategy Shape
The distribution of tests across levels, chosen so that feedback is fast where it can be and confidence is real where it must be.
Zero-Downtime Migration
Changing a schema or system while it stays in service, by adding the new alongside the old, migrating, then removing the old.
A global SaaS product has a 200 ms p95 API budget. Users in Sydney see 900 ms against a single US-East deployment. The application team says the service responds in 40 ms. Who is right and what do you do?
Both are right, and that is the point The service does respond in 40 ms. The other 860 ms is network — and no amount of application profiling will show it, whic
A release must rename a heavily used database column and ships tonight. The team proposes doing the rename in the deployment. What is wrong, and what do you propose?
What is wrong A rename is not additive. During a rolling deployment both versions of the application run simultaneously: one expects the old name, one the new.
Every deployment produces a small spike of 502s that the team has learned to ignore. Fix it.
The cause In flight requests are being severed because the instance terminates before the load balancer has stopped sending to it, or before existing requests c
Knight Capital lost roughly $460M in 45 minutes in 2012 after a deployment reached seven of eight servers. Which architectural failures made that possible, and which one would you fix first?
The case, as publicly reported Per the SEC's 2013 order, Knight Capital deployed new order routing code to eight production servers ahead of a NYSE programme la
p99 latency on checkout tripled overnight. Dashboards look normal, no deployment went out, and every service reports healthy. How do you find it?
What the interviewer is testing Systematic diagnosis in a distributed system when the obvious signals are clean — which is the realistic version of this problem
A marketing site is a client-rendered single-page application. Organic traffic is poor and the team blames the search engine. What is your assessment?
The rendering choice is the problem A marketing page is identical for every visitor and highly cacheable. Rendering it in the browser pays for personalisation t
A team says "backups run nightly and are retained for 30 days". You have one hour to assess whether they could actually recover. What do you check?
The checks, in the order that finds problems fastest 1. When was a restore last performed, and how long did it take? The single most informative question. If th
In July 2019 a single regex deployed globally took Cloudflare's network to 100% CPU within seconds. What does this say about how configuration should be released?
The case, as publicly reported On 2 July 2019, Cloudflare deployed a new managed WAF rule. It contained a regular expression that caused catastrophic backtracki
Deployment Strategies
Rolling, blue-green, canary and shadow, and the traffic and state each one assumes.
Backup Strategies
Scope, immutability, separation, and the restore drill that makes it real.
Caching Strategies
Cache-aside, read-through, write-through and where each belongs.
Data Migration Strategies
Backfill, dual-write, reconciliation and verification.
Deployment Diagrams
What runs where, in which zone, behind which boundary.
Deployment Gates
Automated verification between stages, and the difference between a gate and a delay.
Release Strategies
Blue-green, canary, shadow and progressive delivery.
Rendering Strategies
Client, server, static and incremental rendering, and what each costs on first paint.
Testing Strategies
The pyramid, and the contract tests distributed systems add to it.
Containers
Images, registries, immutability and the deployment model they enable.
ML Platform
Feature stores, training pipelines, registries and deployment.
Micro-Frontends
Independent deployment of UI slices, and the shared runtime that undermines it.