Search the practice set
275 questions, 991 terms and 600 topics in 30 areas.
60 results for “Kappa vs Lambda”
Replay Pipeline
A single processing path that produces both live and historical results by re-running the same code over retained input, replacing the two-path Lambda arrangement.
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.
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.
Containment vs Eradication
Stopping an attacker's ongoing access versus removing their foothold entirely — sequential phases with different urgency and different risks of doing them wrong.
Cost vs Reliability Trade-off
The non-linear relationship between availability and spend, which makes each additional nine roughly an order of magnitude more expensive.
Delivery vs Maintainability
Choosing where to take deliberate shortcuts, based on which kinds of debt are cheap to repay and which compound.
Durability vs Availability
Two different storage guarantees — whether data survives, and whether it can be reached right now — routinely conflated because both are quoted in nines.
ETL vs ELT
Whether data is transformed before loading into the target or after it, which decides where the compute happens and how much raw history you keep.
Event Notification vs Event-Carried State
Whether an event carries only the fact that something happened, or also the data a consumer needs to act on it.
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.
Horizontal vs Vertical Scaling
Adding more machines versus making one machine bigger — and the fact that vertical is underrated for stateful tiers.
Layer 4 vs Layer 7 Load Balancing
Balancing on connection metadata (IP and port) versus on the content of the request (path, host, headers).
Managed vs Self-Managed
Trading control, portability and unit cost against the operational burden of running the thing yourself.
Monolith vs Microservices
A trade of deployment independence against distributed-systems complexity, decided by team topology far more often than by technology.
OLTP vs OLAP
Two workload shapes with opposite requirements — many small indexed transactions versus few large scans and aggregations — which is why they belong in different stores.
Operational vs Analytical Store
The separation between the store serving the application's transactions and the one serving reporting and analysis, and the mechanism connecting them.
Provisioned vs Serverless Capacity
Paying for a fixed database size continuously, versus paying for capacity consumed with automatic scaling — a crossover decision driven by duty cycle.
Re-architect vs Rebuild
Restructuring an existing system incrementally versus writing a replacement from scratch — and the strong evidence that incremental wins.
SQL vs NoSQL
A choice driven by access patterns, consistency requirements and query flexibility — not by data volume, which is the reason usually given.
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.
Strong vs Eventual Consistency
A per-operation decision, not a per-system one: whether this specific read must reflect every completed write.
Synchronous vs Asynchronous Communication
Whether the caller waits for the callee's answer — decided by whether the caller's outcome depends on it, not by latency or taste.
Synchronous vs Asynchronous Replication
Whether a write is acknowledged only after a replica has it, trading write latency against the amount of data a failure can lose.
VPN vs Dedicated Connection
Two ways to link on-premises networks to cloud — an encrypted tunnel over the internet, or a private physical circuit.
Zonal vs Regional Services
Whether a cloud resource lives in one availability zone or is inherently spread across several — a property that determines what a zone failure takes with it.
Access Pattern Driven Modelling
Designing the data model from the queries the application must serve, rather than from an abstract normalised representation of the entities.
Centralisation Trade-off
The exchange between consistency and control gained by centralising a capability and the autonomy and speed retained by distributing it.
A business sponsor asks for a real-time data platform because "the competition has one". Reporting is currently a nightly batch that lands at 06:00 and nobody has complained. How do you handle this?
Do not answer the technology question "Real time platform" is a solution, and it has arrived without a problem attached. Answering it directly leads either to a
A service has widely varying request costs — most complete in 10 ms, some take 5 s. Under round robin some instances are overwhelmed while others idle. What do you change?
Why round robin fails here It distributes by count , not by cost or by whether a backend is coping. With uniform requests that is fine. With a 500× cost spread,
A team of fifteen wants to start a new product as microservices. How do you advise?
Ask what problem microservices are solving here The pattern addresses independent deployment by independent teams, independent scaling of unlike workloads, and
An order API calls six services synchronously and takes 3 seconds at p95, failing whenever any dependency is degraded. Redesign it.
Diagnose with arithmetic Six synchronous dependencies at 99.9% each give 99.4% — roughly four hours a month, from components that are individually fine. And lat
Kappa vs Lambda
One pipeline replayed versus two pipelines reconciled, and the maintenance each carries.
Build vs Buy
Differentiation versus table stakes, priced over five years.
Build vs Buy
Differentiation, five-year TCO, and the exit cost of each option.
Centralised vs Distributed
Shared platform leverage against team autonomy.
Change Advisory vs Automated Gates
Replacing a weekly board with evidence a machine produces on every change.
Change Management vs CD
Reconciling CAB-era controls with continuous delivery without pretending either away.
Control Design vs Operation
A control that is well designed and never runs fails exactly like one that is absent.
Cost vs Reliability
Each nine costing an order of magnitude, and pricing the failure instead.
Delivery vs Maintainability
Fast in the cheap places, careful in the expensive ones.
Erasure vs Immutability
Deletion obligations against event logs, backups and ledgers designed never to forget.
Functional vs Non-Functional
Behaviour versus quality of behaviour, and why only the second constrains structure.
Guardrails vs Gates
Preventing a class of mistake automatically versus stopping to ask a human.
Horizontal vs Vertical Scaling
Scale out for stateless, scale up first for stateful.
Layer 4 vs Layer 7
Connection-level versus request-level balancing, and what each unlocks.
Managed vs Self-Managed
Trading control and unit cost against operational attention.
Monolith vs Microservices
A team-topology decision far more often than a technology one.
Orchestration vs Choreography
A coordinator that knows the flow, or services that react to events.
Performance vs Cost
Buying latency, and knowing what the last millisecond is worth.
Rebuild vs Re-architect
Why greenfield replacement fails, and the narrow cases where it does not.
Reliability vs Complexity
Mechanisms that add availability and add failure modes.
SQL vs NoSQL
Decided by access patterns and query flexibility, not by data volume.
Security vs Usability
Varying control by the value of the action rather than uniformly.
Self-Service vs Governed
Letting analysts move fast without four teams reporting four different revenues.
Serverless vs Containers
Spiky and event-driven versus sustained throughput.
Single vs Multi-Region
Driven by RTO, RPO and residency rather than by ambition.
Streaming vs Batch
The freshness requirement that actually justifies streaming, and the cost of assuming one.
Strong vs Eventual Consistency
A per-operation decision, resolved by what a stale read would cost.
Sync vs Async
Whether the caller's outcome depends on the callee's response.