Elect new IC/GuestOS revision (commit 79c0105)

Release Notes for release-2026-08-20_03-30-base (79c01052b5f7f49d3cf53d04d696cb2893294cd3) This release is based on changes since release-2026-08-13_03-55-base (59c42492cd6ee3ef5e60cd35d7b766e7bfd085da).

Please note that some commits may be excluded from this release if they're not relevant, or not modifying the GuestOS image. Additionally, descriptions of some changes might have been slightly modified to fit the release notes format.

To see a full list of commits added since last release, compare the revisions on GitHub.

Features:

• d54472dd1 Core Protocol: ic0_subnet_self_node_count (#11132)
• 0e0f48361 Core Protocol: Add replicated state metric for the total value of pending anonymous refunds (#11170)
• 826017d58 Core Protocol: make canister_info a query method of the management canister (#11154)
• f48a8ce8d Core Protocol: Delete canister directory via UnflushedCheckpointOp::DeleteCanister (#11158)
• 655cdf32c Core Protocol: Add replicated state metrics for ingress history, queues, call contexts and refunds (#11010)
• 805c3af86 Core Protocol: Async HTTP outcalls refunds (#11113)
• f227e5c95 Core Protocol: Do not route canister messages to a cooling down subnet (#11129)
• 6ca30003d Core Protocol: migrate to ic-cdk 0.20 (#11069)
• f84327316 Core Protocol: Respect query limits from the registry (#11111)
• 27004e0d4 Core Protocol: Lazy hashing of canister modules (#11133)
• 22f461c96 Core Protocol: Cap the amount of cycles that move into the per-replica HTTP outcalls allowance (#11012)
• 43d77537c Core Protocol: Add a version_id field to ReplicaVersionRecords (#10942)
• 9e5a134a9 Core Protocol: Non-flexible out of cycles error (#11085)
• ec265894e Node: use pure-Rust libsystemd crate (#11163)

Bugfixes:

• 59892f8e3 Core Protocol: Consider reject responses when estimating new HTTP outcalls cost (#11161)
• fbfb8dbeb Core Protocol: validate the Wasm memory in create_execution_state (#11168)
• 440ca1dab Core Protocol: tolerate a cycles balance increase on DTS resume (#11141)
• 2c2e64d2d Core Protocol: account for install_code debit when loading a canister snapshot (#11152)
• 44ae9a3f1 Core Protocol(canister_logging): reject a log_memory_limit below one page (#11155)
• 1cad024f2 Core Protocol: dynamic HTTP outcalls per-replica cycles limit (#11143)
• e1a7d3a6e Core Protocol: CanisterDidNotReply for failed calls in composite queries (#11104)
• a87fac145 Core Protocol: check the cycles balance and charge executed instructions on DTS resume (#11039)
• 95c917e23 Node: drop second arg in selinux policy (#11147)

Performance improvements:

• 54e87a08f Core Protocol: Correct limit of derivation path length (#11192)
• 6f848ae87 Core Protocol(key-manager): optimize some clones (#11131)

Chores:

• 42b6c141d Core Protocol: Even better error messages for invalid keys (#11198)
• 2c31ebb0e Core Protocol(idkg): update ID generator's height together with the transcripts' references (#11156)
• 71e81592e Core Protocol: simplify memory retrieval on upgrade and clarify preserving the memories on upgrade (#11157)
• ce4b27fb0 Core Protocol: Manually implement serde for Cycles and CBOR (#11148)
• 77aeae9c3 Core Protocol: Adjust instruction overhead (#11146)
• cea9c9fde Node: remove systemd from build container (#11182)
• 51ddfcf13 Node: Cleanup backup resizing (#11137)
• eb5587356 Node: Small misc comment fixes (#11106)
• 6d2d6c6a7 Node: Use a tar lib instead of shelling out in fs build (#11107)
• d04e42169 Node: Update Base Image Refs [2026-08-13-0830] (#11125)

Refactoring:

• 484709584 Core Protocol: drop the legacy canister_log store from SystemState (#10821)
• 6bd6690d3 Core Protocol: install the canister memories in create_execution_state (#11142)
• a3c4f796f Core Protocol: snapshot memory size validation (#11118)

Tests:

• f8d5ae24c Core Protocol: Fix tests asserting on ReplicatedStateMetrics (#11110)

Other changes:

Full list of changes (including the ones that are not relevant to GuestOS) can be found on GitHub.

IC-OS Verification

To build and verify the IC-OS GuestOS disk image, after installing curl if necessary (sudo apt install curl), run:

# From https://github.com/dfinity/ic#verifying-releases
curl -fsSL https://raw.githubusercontent.com/dfinity/ic/79c01052b5f7f49d3cf53d04d696cb2893294cd3/ci/scripts/repro-check | python3 - -c 79c01052b5f7f49d3cf53d04d696cb2893294cd3 --guestos

The two SHA256 sums printed above from a) the downloaded CDN image and b) the locally built image, must be identical, and must match the SHA256 from the payload of the NNS proposal.

While not required for this NNS proposal, as we are only electing a new GuestOS version here, you have the option to verify the build reproducibility of the HostOS by passing --hostos to the script above instead of --guestos, or the SetupOS by passing --setupos.