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275 questions, 991 terms and 600 topics in 30 areas.
60 results for “Abstraction Level Choice”
Leaky Abstraction Cost
What a consumer pays when a platform abstraction hides a mechanism they must nonetheless understand to diagnose or tune it.
Abstraction Level Discipline
Keeping each diagram to a single level of zoom, and providing separate diagrams for each level rather than one diagram attempting all of them.
C4 Model
A set of four nested diagram levels — context, container, component, code — that keeps each diagram at one consistent level of abstraction.
Dependency Inversion
The rule that high-level policy should not depend on low-level detail, both depending instead on an abstraction owned by the policy.
Presenting to Executives
Leading with the decision and the business consequence, at a level of abstraction where technology names do not appear.
Abstraction
Exposing what a component does while hiding how it does it, so callers depend on the contract rather than the mechanism.
Consistency Level Selection
Choosing the consistency guarantee per operation rather than per system, matching the cost of coordination to the business consequence of staleness.
Fairness Definition Choice
Selecting which mathematical fairness criterion applies, given that the main criteria are provably incompatible and the choice is a value judgement.
Field-Level Encryption
Encrypting specific sensitive fields in the application before they reach the datastore, so the store never holds plaintext.
Leaky Abstraction
An abstraction whose underlying implementation details become visible or consequential, requiring users to understand what it was meant to hide.
Log Level Discipline
Consistent semantics for log severity so that levels can be used for routing, alerting and cost control.
Object-Level Authorization
Checking that the caller is entitled to the specific record they requested, not merely that they may call the endpoint.
Service Level Agreement
A contractual commitment about service level, with a defined remedy — usually a service credit — when it is missed.
Service Level Indicator
The actual measurement of a service's behaviour that an objective is set against — a ratio of good events to valid events.
Service Level Objective
An internal target for a service level indicator, set below the level at which users notice, and used to decide whether to ship or to stabilise.
Active-Active vs Active-Passive
Whether all regions serve traffic simultaneously, or one serves while another waits to take over — a choice about which failure mode you would rather have.
Architectural Debt
Structural compromises that increase the cost of all future change, distinguished from code-level debt by being expensive and slow to repay.
Authentication
Establishing who a principal is, to a defined level of confidence.
Build vs Buy
The choice between developing a capability in-house and acquiring it, decided on differentiation and total cost rather than on feature lists.
Cardinality Estimation
The planner's prediction of how many rows each step of a query will produce — the input that determines every other choice it makes.
Cell Isolation
Bulkheading at the level of a complete system copy, so that any failure — including ones nobody predicted — is contained to the customers assigned to one cell.
Change Data Capture
Publishing a stream of a database's row-level changes by reading its replication log, without modifying the application that owns it.
Clean Architecture
Concentric layers with a strict dependency rule — source code dependencies point only inwards, towards higher-level policy.
Cost Allocation Tagging
A mandatory, enforced tagging scheme that attributes every resource to an owner, so spend can be understood and acted on below the level of the whole account.
Dashboard Hierarchy
Organising dashboards into service-level, diagnostic and deep-dive layers so each answers a specific question at a specific moment.
Data Lineage
A record of where each dataset came from, what transformed it, and what depends on it — traced at table and ideally column level.
Fail-Fast vs Fail-Safe
Whether a component should stop immediately on detecting a problem, or continue in a degraded but safe mode — a choice that depends entirely on which outcome is worse.
Fan-Out Latency Amplification
The effect by which a request that depends on many parallel sub-requests is governed by the slowest of them, so rare slowness becomes common at the user level.
Forward Fix
Resolving an incident by shipping a correction rather than reverting, which is the right choice exactly when reverting is not actually available.
Mentoring Ladder
Adjusting the level of direction given to someone according to their experience with the specific task, from demonstration through to sponsorship.
Partition Tolerance
The ability to keep operating when the network drops or delays messages between nodes — not a choice, but a property of any system spanning more than one machine.
Power-Interest Grid
A classification of stakeholders by their influence over a decision and their level of concern with it, used to allocate communication effort deliberately.
Predicate-Based Filtering
A policy that appends a filter to every query on a table based on who is asking, so one physical table serves many audiences safely.
Presenting to Engineers
Presenting a design at the level of mechanism, including the alternatives rejected and the parts you are still unsure about.
Quality Dimension Threshold
The stated numeric level at which a dataset is fit for its purpose on a given quality dimension, plus what happens when it is not met.
Reversibility
The property of a decision that determines how much analysis it deserves, since a cheaply reversible choice can be tested rather than debated.
Reversible Decision
A choice that can be undone cheaply, and which therefore deserves far less deliberation than an irreversible one.
Risk Tolerance Statement
The board-level declaration of how much of each risk type the organisation will accept, which is what tells an architect which risks may be accepted without escalation.
SQL vs NoSQL
A choice driven by access patterns, consistency requirements and query flexibility — not by data volume, which is the reason usually given.
Saturation Point
The load level beyond which additional demand produces queueing and latency growth rather than additional completed work.
Security Group
A stateful, instance-level firewall that allows specified traffic and denies everything else by default.
Security vs Usability
A trade-off that is usually resolved by varying the control with the value of the action, rather than by choosing a uniform level of friction.
A new platform must serve a public partner API, three internal front-ends with different data needs, and high-volume service-to-service traffic. Choose the API styles and defend the choice.
Resist "pick one" These are three different problems with three different consumers. Standardising on one style optimises for architectural tidiness at the expe
An order service must notify inventory, billing, shipping and analytics when an order is placed. Synchronous calls or events? Justify your choice per consumer.
What the interviewer is testing Whether you apply the decision per interaction rather than adopting one style globally. The framing that matters Synchronous cal
Prime Video reported a 90% cost cut by consolidating a serverless distributed service into one process. Does that mean microservices were the wrong choice, and what is the actual decision rule?
What actually happened The Prime Video Video Quality Analysis team's 2023 post describes an audio/video monitoring service built as Step Functions orchestrating
Abstraction Level Choice
How much to hide, and the leak that turns a helpful abstraction into a trap.
Abstraction & Encapsulation
Hiding mechanism behind contract, and protecting invariants by owning state.
Row & Column-Level Security
Restricting slices of a table rather than the whole table, and where it is enforced.
Architecture Diagrams
Choosing an audience and refusing to mix levels of abstraction.
Architecture Styles
System-level organising shapes, and how they differ from problem-level patterns.
CAP & PACELC
What you must give up during a partition, and the latency choice the rest of the time.
Caching for Performance
Layer choice, hit ratio as a first-class metric, and cold-cache recovery.
Design Patterns
Reusable solutions at code level, and when they become ceremony.
Layer 4 vs Layer 7
Connection-level versus request-level balancing, and what each unlocks.
Logging
What to log, at what level, and what must never appear in a log.
Secure API Design
Object-level authorisation, input validation and safe error responses.