Catalyst offers two function types: Advanced I/O functions for handling HTTP requests and returning responses, and Basic I/O functions for lightweight data processing triggered by events or crons. You write the function code locally using the Catalyst CLI, test it in a local environment, and deploy it with a single command. Catalyst provisions the runtime, manages cold starts, and scales concurrently across invocations with no configuration required from the developer.
Use serverless functions for any backend logic that does not need a permanently running server, such as processing webhook payloads, generating PDF reports on demand, or validating form submissions before storing data. Indian SaaS startups building on top of Zoho CRM use Catalyst functions to extend CRM workflows with custom logic, such as calculating discounts or calling third-party payment APIs, without maintaining a separate Node.js server.
Serverless functions have a maximum execution timeout of 60 seconds per invocation, so long-running operations such as bulk data processing should be split into smaller chunks or triggered iteratively via cron. Cold start latency can affect user-facing functions; keeping functions small and avoiding heavy dependencies in the initialisation path reduces this. Catalyst charges based on invocation count and compute time, so high-volume functions should be cost-modelled before production deployment.
A Bengaluru-based HR tech startup uses a Catalyst serverless function to generate offer letters as PDFs. When a recruiter marks a candidate as “Selected” in Zoho CRM, a webhook triggers the function, which fetches candidate details from the Catalyst Datastore, fills a template, and stores the resulting PDF in Catalyst File Store. The whole process completes in under three seconds with no server to maintain.
Catalyst supports Node.js and Java for serverless functions. Node.js is the more commonly used option due to its fast cold start times and the availability of npm packages. Java is suitable for teams that already have Java expertise or need specific JVM libraries.
Catalyst scales function invocations automatically. When multiple requests arrive simultaneously, Catalyst runs concurrent instances of the function without any configuration. There is no server pool to size or auto-scaling policy to define. This makes it practical for workloads with unpredictable traffic patterns, such as batch jobs triggered by external events.
Aaxonix is a certified Zoho implementation partner based in Pune. Architecture-first, no surprises.