stable-fs
A WASI-compatible filesystem for Internet Computer canisters, backed by stable memory so data survives upgrades.
Features
- Stable across upgrades — files and directories are stored in IC stable memory, no data loss on canister upgrade
- WASI interface — implements the standard WASI filesystem API for drop-in use with Wasm modules
- Memory mounting — mount an IC stable memory region directly as a file, with configurable size policies
Storage backends
| Backend | Description |
|---|---|
StableStorage |
Persists in IC stable memory — use this in production canisters |
TransientStorage |
In-memory only — useful for unit tests |
Limitations
- Symbolic links are not supported
allocate()does not reserve space ahead of time