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Runtime and System Modules

System APIs for canister identity, cycles, time, and low-level memory.

Runtime (mo:core/Runtime)​

Core runtime hooks for module identity, caller identity, traps, and unique runtime values. See Runtime for the full API.

Time (mo:core/Time)​

Time helpers and types. See Time for the full API.

Timer (mo:core/Timer)​

Async timer scheduling. Timer jobs use ordinary async functions, so the same async/await interleaving rules apply once the job runs. See Timer for the full API.

Cycles (mo:core/Cycles)​

Cycles accounting. See Cycles for the full API.

CertifiedData (mo:core/CertifiedData)​

Access to certified data and certificates. See CertifiedData for the full API.

Region (mo:core/Region)​

Region-based memory operations. See Region for the full API.

InternetComputer (mo:core/InternetComputer)​

Low-level IC system queries. The instruction-counting and performance-counter helpers are trusted runtime interfaces, so use them for measurement and resource checks rather than as deep proof facts. See InternetComputer for the full API.

Summary​

  • Runtime exposes identity and proof-related hooks such as moduleHash, callerId, and callerActorHash.
  • Time and Timer provide basic time and scheduling utilities.
  • Cycles, CertifiedData, Region, and InternetComputer expose IC system APIs.