Knockout API vs MockServer

Knockout API provides image and video processing through a browser app and API. Its image tools cover background removal and replacement, batch processing, masking, smart crop, stickers, outlines, shadows, and inpainting; the API also handles upscaling, portrait restoration, colorization, and object removal. Video background removal runs asynchronously, with job polling for progress. The browser Canvas supports layered designs with text and effects, and users can save canvases and cutouts to a free account. Developers can connect through REST, any HTTP client, or official Node, React, Python, and CLI options. The service says it manages GPU processing, endpoint updates, usage records, credentials, teams, and billing. Its privacy policy says uploaded images are processed in GPU worker memory, not retained after the response, and not used to train models. The Free plan is free, with 30 images per month and 60 requests per minute. Pay-as-you-go is $0.02 a month, with metered usage billed monthly; Plus is $10 a month. Paid tiers have no monthly cap and a 600-request-per-minute limit.

MockServer is a free, self-hosted tool for mocking and proxying HTTP, HTTPS, and gRPC services during isolated testing. It can verify requests as well as stand in for services. Teams can generate mocks and validate traffic against OpenAPI or Swagger contracts, or import recorded sessions from browser HAR files and Postman collections. Beyond HTTP services, it can mock gRPC, AsyncAPI brokers such as Kafka, MQTT, and AMQP, and OAuth2/OIDC providers. Its protocol coverage includes HTTP/1.1, HTTP/2, HTTPS, SOCKS, and experimental HTTP/3, which uses a separate UDP port. For fault-oriented testing, it can add latency, errors, dropped connections, and malformed responses to mocked or proxied traffic. Deployment options include Docker, an executable JAR, Helm/Kubernetes, Testcontainers, Homebrew, and a JVM-less bundle. A web dashboard displays logs, expectations, and recorded traffic; Prometheus metrics and OpenTelemetry tracing are available for shared environments. Each instance includes an MCP server at /mockserver/mcp. The /mockserver/status and /mockserver/ready probes remain reachable without authentication or authorization.