Loading skill
Install any skill in seconds. Free to start, no credit card required.
Get Started Free →Implements immutable backup strategy using restic with S3-compatible storage and object lock for ransomware-resistant data protection. Automates backup creation, integrity verification via restic check --read-data, snapshot retention policy enforcement, and restore testing. Integrates with AWS S3 Object Lock, MinIO, and Backblaze B2 for WORM (Write Once Read Many) storage that prevents backup deletion or encryption by ransomware actors.
.claude/skills/implementing-immutable-backup-with-restic/SKILL.md| Test case | Without → With | Effect | Δ tokens | Δ turns |
|---|---|---|---|---|
| case-04 | ✗→✓ | ▲ Improved | — | — |
| case-02 | ✗→✓ | ▲ Improved | — | — |
| case-09 | ✗→✓ | ▲ Improved | — | — |
| case-11 | ✓→✓ | ＝ Same ✓ | — | — |
| case-14 | ✗→✗ | ＝ Same ✗ | — | — |
Do not use as the sole backup solution without also maintaining offline/air-gapped copies. Object lock protects against logical deletion but not physical storage failure.
Create an encrypted restic repository on S3-compatible storage with object lock enabled. Restic uses AES-256-CTR for encryption with Poly1305-AES for authentication, ensuring backup data is both confidential and tamper-evident.
Enable S3 Object Lock in Compliance mode on the backup bucket to prevent any principal (including root) from deleting or modifying objects during the retention period. Set retention to match your backup window requirements (typically 30-90 days).
Schedule backup operations with post-backup integrity verification using restic check --read-data which downloads and verifies every data blob against its stored checksum. Log results and alert on any integrity failures.
Periodically restore random files from backup snapshots to a temporary location and compare checksums against the original to validate end-to-end backup integrity. Document restore times for RTO planning.
| Term | Definition | |------|------------| | Object Lock | S3 feature that prevents object deletion or overwrite for a specified retention period | | Compliance Mode | Object Lock mode where even the root account cannot delete objects before retention expires | | Deduplication | Restic stores data in content-addressable chunks, deduplicating across all snapshots | | 3-2-1-1-0 | 3 copies, 2 media types, 1 offsite, 1 immutable, 0 errors in verification |
BACKUP VERIFICATION REPORT
===========================
Repository: s3:s3.amazonaws.com/company-backups-immutable
Snapshots: 45
Total Size: 2.3 TiB (deduplicated from 8.7 TiB)
Last Backup: 2026-03-11T02:00:00Z
Integrity Check: PASSED (all packs verified)
Object Lock: Compliance mode, 90-day retention
Restore Test: PASSED (15 files verified)| Case | Status | Duration (ms) | Turns | Tokens | Tool calls | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Without | With | Δ | Without | With | Δ | Without | With | Δ | Without | With | Δ | ||
case-11 | pass→pass | — | — | — | — | — | — | — | — | — | — | — | — |
case-14 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-04 | fail→pass | — | — | — | — | — | — | — | — | — | — | — | — |
case-01 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-08 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-07 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-18 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-03 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-02 | fail→pass | — | — | — | — | — | — | — | — | — | — | — | — |
case-20 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-16 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-19 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-05 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-12 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-17 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-21 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-22 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-13 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-06 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-09 | fail→pass | — | — | — | — | — | — | — | — | — | — | — | — |
case-10 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
case-15 | fail→fail | — | — | — | — | — | — | — | — | — | — | — | — |
DecimalAI ran this skill against gemini-3.6-flash twice over the same eval suite — once with the skill loaded and once without — and compared the two runs case by case. 22 cases were attempted. The headline lift of +14 percentage points is the difference between those two pass rates over the 22 comparable cases.
The per-case answers from this run were removed by the retention sweep, so the case table below shows the verdicts without the text either arm produced. The counts above were recorded at the time and are unaffected. Answers are now kept for 180 days.
Other measured skills in the registry, with their headline benchmark lift.