Glossary

12-Factor App

Twelve-Factor Application

A methodology of twelve best practices for building scalable, maintainable software-as-a-service applications.

API Gateway

A server that acts as a single entry point for API requests, handling routing, authentication, and rate limiting.

AST

Abstract Syntax Tree

A tree representation of the syntactic structure of source code, used by compilers and code analysis tools.

Backpressure

Stream Backpressure

A flow control mechanism where a slow consumer signals a fast producer to reduce its output rate, preventing buffer overflow.

Base58

Base58 Encoding

A binary-to-text encoding that excludes visually ambiguous characters (0, O, I, l), used in Bitcoin addresses.

Canary Release

Canary Deployment

A deployment strategy that routes a small percentage of traffic to a new version to detect issues before full rollout.

CI/CD

Continuous Integration / Continuous Deployment

A development practice where code changes are automatically built, tested, and deployed to production.

CIDR

Classless Inter-Domain Routing

A notation for IP address ranges using a base address and prefix length (e.g. 192.168.1.0/24).

Content Negotiation

HTTP Content Negotiation

A mechanism where the client and server agree on the best representation of a resource using Accept headers.

CORS Preflight

CORS Preflight Request

An automatic OPTIONS request sent by browsers before cross-origin requests to check server permissions.

Cron Expression

Cron Schedule Expression

A string format representing a schedule using five fields: minute, hour, day, month, and day of week.

Dead Letter Queue

Dead Letter Queue (DLQ)

A message queue that stores messages that could not be processed successfully, enabling later inspection and retry.

Debounce

Function Debouncing

Delaying a function execution until a specified time has passed since the last invocation.

Diff Algorithm

Difference Algorithm

An algorithm (e.g. Myers, patience) that computes the minimal set of changes between two sequences of text.

DNS

Domain Name System

The hierarchical naming system that translates human-readable domain names into IP addresses.

Docker

Docker Container Platform

A platform for building, shipping, and running applications in lightweight, isolated containers that share the host OS kernel.

Edge Computing

Processing data closer to the user at network edge locations to reduce latency and bandwidth usage.

Endian Swap

Byte Order Swap

Reversing the byte order of a multi-byte value, converting between big-endian and little-endian formats.

Environment Variable

A key-value pair set in the operating system environment, used to configure application behavior.

Epoch Time

Unix Epoch Timestamp

The number of seconds elapsed since January 1, 1970 UTC, used as a universal time reference.

ETag

Entity Tag

An HTTP header providing a unique identifier for a specific version of a resource, used for cache validation.

Feature Flag

Feature Flag (Feature Toggle)

A configuration switch that enables or disables features at runtime without deploying new code, used for gradual rollouts and A/B testing.

Glob Pattern

Glob Pattern Matching

A wildcard syntax for matching file paths using characters like * (any) and ? (single character).

GraphQL

Graph Query Language

A query language for APIs that lets clients request exactly the data they need in a single request.

gRPC

gRPC Remote Procedure Call

A high-performance RPC framework using HTTP/2 and Protocol Buffers for efficient service-to-service communication.

Hex Encoding

Hexadecimal Encoding

Representing binary data as a string of hexadecimal (base-16) characters, using digits 0-9 and letters A-F.

HTTP Status Code

HTTP Response Status Code

A three-digit code indicating the result of an HTTP request (e.g. 200 OK, 404 Not Found, 500 Server Error).

Idempotent

Idempotent Operation

An operation that produces the same result regardless of how many times it is applied.

ISO 8601

ISO 8601 Date Format

An international standard for date and time representation (e.g. 2026-03-08T14:30:00Z).

JQ

JQ Command-Line Processor

A lightweight command-line tool for filtering, transforming, and querying JSON data using a concise syntax.

JSON Lines

JSON Lines (NDJSON)

A text format where each line is a valid JSON value, designed for streaming and log processing one record at a time.

JSON Patch

JSON Patch (RFC 6902)

A format for describing a sequence of operations to modify a JSON document (add, remove, replace, move).

JSON Schema

A vocabulary for annotating and validating the structure, types, and constraints of JSON documents.

Kubernetes

Kubernetes Container Orchestration

An open-source system for automating deployment, scaling, and management of containerized applications across clusters.

Microservices

Microservices Architecture

A design pattern where an application is composed of small, independently deployable services communicating via APIs.

Monorepo

Monolithic Repository

A version control strategy where multiple projects or packages are stored in a single repository, simplifying dependency management.

OAuth 2.0

OAuth 2.0 Authorization Framework

An authorization protocol allowing third-party applications to access resources on behalf of a user without sharing credentials.

OpenAPI

OpenAPI Specification

A standard for describing RESTful APIs in a machine-readable format (formerly known as Swagger).

Polyfill

Browser Polyfill

JavaScript code that implements a modern API on older browsers that lack native support, enabling cross-browser compatibility.

Protocol Buffers

Protocol Buffers (Protobuf)

A language-neutral binary serialization format by Google, more compact and faster than JSON or XML.

Rate Limiting

API Rate Limiting

Restricting the number of API requests a client can make within a given time window.

REST

Representational State Transfer

An architectural style for web APIs using standard HTTP methods to access and manipulate resources.

RFC

Request for Comments

A publication by internet standards bodies like the IETF that defines protocols, procedures, and conventions for internet technologies.

Semver

Semantic Versioning

A versioning scheme using MAJOR.MINOR.PATCH format to communicate the nature of changes in software.

Serverless

Serverless Computing

A cloud execution model where the provider manages server infrastructure and scales automatically per request.

Service Worker

A browser script running in the background that enables offline caching, push notifications, and network interception.

Shebang

Shebang Line

The #! characters at the start of a script file specifying which interpreter should execute it.

Source Map

JavaScript Source Map

A file mapping minified or transpiled code back to the original source, enabling readable stack traces during debugging.