SR-9(1): Multiple Stages of System Development Life Cycle

SR-9(1) requires you to employ anti-tamper technologies, tools, and techniques across multiple stages of your system development life cycle (SDLC), not just at release. To operationalize it fast, define “anti-tamper” expectations per SDLC phase, embed them into engineering workflows (requirements, build, test, deploy), and retain objective evidence that controls ran and were reviewed. ¹

Key takeaways:

• SR-9(1) is a “throughout SDLC” control: you need anti-tamper measures in design, build, test, delivery, and updates, with evidence at each stage. ¹
• Auditors will look for repeatable mechanisms (tooling + process) and artifacts that prove the mechanisms ran for real releases, not a one-time policy.
• The fastest path is a phase-by-phase anti-tamper checklist mapped to control owners, pipeline gates, and recurring evidence packages.

The sr-9(1): multiple stages of system development life cycle requirement is part of NIST SP 800-53’s Supply Chain Risk Management family and focuses on tampering risk while systems are being built, integrated, delivered, and updated. The operational trap is treating “anti-tamper” as a single feature (for example, a code-signing step) and declaring it done. SR-9(1) expects coverage across the SDLC, meaning you can explain what you do to prevent, detect, and respond to unauthorized modifications at several points where tampering commonly occurs: source control, build environments, dependencies, artifacts, and release channels. ¹

For a Compliance Officer, CCO, or GRC lead, your job is to translate this into enforceable engineering requirements, make ownership unambiguous, and collect evidence that stands up in an assessment. This page gives you requirement-level implementation guidance you can hand to Engineering and Product Security: what to implement in each SDLC stage, how to verify it, and what artifacts to retain so you are not rebuilding the story during an audit.

Regulatory text

Requirement (SR-9(1)): “Employ anti-tamper technologies, tools, and techniques throughout the system development life cycle.” ¹

Operator interpretation (what you must do):

• Define what “anti-tamper” means for your environment (code, infrastructure-as-code, firmware, container images, CI/CD pipelines, third-party components).
• Implement preventative and detective controls at multiple SDLC stages (not only at deployment).
• Produce evidence that these controls ran on real changes and releases, and that exceptions are governed. ¹

Plain-English interpretation

SR-9(1) requires you to make tampering hard and detectable from the moment code is written to the moment software (and updates) reach production or customers. “Throughout the SDLC” means you need more than end-stage inspection. You need controls earlier where attacks often happen quietly: developer workstations, source control, dependency intake, build systems, artifact repositories, and release processes.

Anti-tamper in practice includes:

• Integrity protections (prevent unauthorized modification): signed commits, protected branches, least privilege on build systems, immutable artifact repositories.
• Integrity verification (detect modification): hashes, signature verification, reproducible build checks where feasible, integrity monitoring on CI runners.
• Provenance (prove what was built and from what): build attestations, SBOMs, traceability from ticket → commit → build → deployment.

Who it applies to

Entity scope

• Federal information systems and contractors handling federal data that implement NIST SP 800-53 controls as part of an authorization, contractual requirement, or internal control baseline. ²

Operational scope (where the control “lives”)

• Product engineering teams building applications, services, or firmware.
• Platform/DevOps teams running CI/CD, build agents/runners, artifact registries, package repositories, and deployment tooling.
• Security/PSIRT or product security teams defining secure build and release requirements.
• Third-party and open-source intake processes (because tampering risk often enters via dependencies and build tooling).

What you actually need to do (step-by-step)

Step 1 — Assign ownership and define SDLC stages you will control

1. Name a control owner (often Product Security or DevSecOps) and operators (CI/CD platform team, repo admins).
2. Define your SDLC stages as you run them (example: Plan/Design → Code → Build → Test → Release → Deploy/Operate → Patch/Update).
3. For each stage, decide what “tampering” means and what assets must be protected (source code, build scripts, signing keys, artifacts).
   Practical shortcut: create a one-page RACI plus a stage list, then attach it to your secure SDLC standard.

Step 2 — Establish an anti-tamper control set per SDLC stage (minimum viable)

Use a stage-by-stage checklist that engineering can implement and auditors can understand.

SDLC stage	Anti-tamper controls to implement	What “good” looks like (testable)
Code (SCM)	Protected branches, mandatory reviews, signed commits where feasible, restricted admin actions	Unauthorized pushes are blocked; changes have attributable reviewers; repo settings are auditable
Dependency intake	Pinning/lockfiles, trusted registries, checksum/signature validation for critical components	Builds fail when dependency integrity checks fail; exceptions require approval
Build	Hardened build runners, ephemeral build workers, least privilege, build logs retained, controlled secrets access	Build environment changes are reviewed; builds are traceable to commits
Artifact management	Immutable artifact repository, signing of artifacts, access controls and logging	Artifacts can be verified as untampered; overwrites are blocked or tightly controlled
Release	Release approvals, signature verification gates, separation of duties for signing keys	Only approved builds are released; key use is logged and monitored
Update/Patch	Signed updates, secure distribution channel integrity checks, rollback protections	Clients/production reject unsigned or altered updates

Your exact control choices vary by architecture, but the control design must show coverage at multiple points “throughout” the SDLC. ¹

Step 3 — Implement pipeline “gates” so anti-tamper controls run by default

Policy statements do not stop tampering. Put enforcement into tooling:

• CI checks that verify signatures/hashes for build inputs.
• Build steps that generate and store provenance (attestation) and tie it to artifact IDs.
• Release gates that require signed artifacts and documented approvals.
• Automated drift detection for build configuration (for example, detecting unauthorized changes to CI templates).

CCO/GRC action: require Engineering to document which gates are blocking vs monitoring, and who can change gate rules.

Step 4 — Govern keys, secrets, and privileged SDLC access

Anti-tamper fails quickly if signing keys or CI admin accounts are loosely controlled. Require:

• Defined owners for signing keys, rotation and access approval, and logging of key use.
• Privileged access controls for CI/CD administration and artifact repository administration.
• Break-glass procedures with after-action review for emergency releases.

Step 5 — Build an evidence package that can be sampled per release

Design your evidence so an assessor can pick a recent release and you can prove anti-tamper controls were applied across stages. For each sampled release, you want traceability:

• Ticket/requirement → code changes → build run → test results → artifact in repository → release approval → deployment record.

Step 6 — Add third-party and open-source touchpoints

SR-9(1) sits in supply chain risk management, so incorporate third-party realities:

• Require integrity controls for third-party components you build into production (libraries, container base images, build actions/plugins).
• Ensure contracts or security addenda for critical third parties address build integrity where they deliver code or artifacts to you.
• For internally hosted forks/mirrors, control write access and validate upstream updates.

Required evidence and artifacts to retain

Keep artifacts that prove operation, not intent. A practical evidence set:

• Secure SDLC / anti-tamper standard that maps controls to SDLC stages and owners.
• SCM configuration exports or screenshots: branch protection rules, required reviews, who has admin rights.
• CI/CD configuration and change history: pipeline definitions, approvals for pipeline changes, logs from key jobs.
• Build and release logs for sampled releases showing integrity checks executed (pass/fail).
• Artifact signing records: signing policy, verification results, and where signatures are stored.
• Access control lists for artifact repositories and CI/CD admin roles, plus audit logs for changes.
• Exception register: documented deviations (what, why, risk acceptance, compensating controls, expiration).

If you need a fast way to manage this, Daydream can help you map SR-9(1) to a control owner, implementation procedure, and recurring evidence artifacts so releases generate an audit-ready packet without manual scrambles. ¹

Common exam/audit questions and hangups

Expect assessors to probe “throughout the SDLC” claims:

• “Show me how you prevent unauthorized modification of source code and build definitions.”
• “Pick a recent release. Prove the artifact deployed to production matches the artifact produced by CI.”
• “Who can bypass branch protections or release gates, and how is that monitored?”
• “How do you detect tampering in third-party components or build tooling?”
• “What happens if integrity checks fail? Is release blocked or only alerted?”

Common hangup: teams can describe controls verbally but cannot produce objective evidence for a sampled release.

Frequent implementation mistakes and how to avoid them

1. Only signing at the end of the pipeline.
   Fix: add integrity checks for inputs (dependencies, build scripts) and lock down SCM and build environments earlier.

2. Controls exist, but exceptions are informal.
   Fix: require time-bound exceptions with approver, rationale, and compensating controls.

3. CI/CD is treated as “ops tooling,” outside compliance scope.
   Fix: explicitly scope CI/CD, artifact repos, and signing infrastructure as in-scope systems for SR-9(1).

4. No separation of duties for releases.
   Fix: define who can approve releases, who can modify gates, and who can access signing keys; document and review regularly.

5. Evidence is screenshot-heavy and inconsistent.
   Fix: standardize an evidence checklist per release and automate exports/log retention.

Enforcement context and risk implications

No public enforcement cases were provided for this requirement in the supplied sources, so you should treat SR-9(1) primarily as an assessment and authorization risk: if you cannot demonstrate anti-tamper controls across SDLC stages, you risk failed assessments, delayed ATO decisions, contractual noncompliance findings, and increased exposure to software supply chain attacks. ²

Practical 30/60/90-day execution plan

First 30 days (Immediate stabilization)

• Assign control owner and publish an SR-9(1) implementation memo: SDLC stages, in-scope systems, and minimum anti-tamper requirements.
• Inventory build pipelines, artifact repositories, signing mechanisms, and who administers them.
• Pick one “reference product” and define the evidence package you will produce per release.

Days 31–60 (Embed controls into engineering workflows)

• Implement or tighten SCM protections (branch protections, review requirements, admin restrictions).
• Add CI gates for dependency integrity and artifact signing/verification for the reference product.
• Stand up an exception workflow with required fields and approvals, then socialize it with engineering leads.

Days 61–90 (Scale and prove operating effectiveness)

• Expand the control set to other products and shared pipelines.
• Run an internal sample-based review: pick releases and validate you can show traceability and integrity checks across stages.
• Operationalize recurring evidence collection (automated logs, configuration exports, and a standardized release evidence packet).

Frequently Asked Questions

Does SR-9(1) require specific anti-tamper tools?

No specific tools are named in the requirement text. You must employ “technologies, tools, and techniques” across the SDLC and be able to prove they operate for real builds and releases. ¹

What counts as “throughout the SDLC” for a SaaS team shipping daily?

Define stages that match your delivery model (code, build, test, release, deploy, update) and place enforceable integrity controls at multiple points. Daily shipping is fine if controls run automatically and you can evidence them per sampled release. ¹

Are SBOMs required for SR-9(1)?

The text does not explicitly require SBOMs. SBOMs can support anti-tamper objectives by improving provenance and component traceability, but you should treat them as an implementation option rather than a textual mandate. ¹

How do we handle third-party developers or contractors contributing code?

Apply the same SCM and review controls to their access, and ensure accounts are uniquely identified and governed. If they deliver artifacts instead of code, require integrity verification (signatures/hashes) and controlled intake into your build process. ²

What evidence is strongest in an audit for SR-9(1)?

Release-level traceability with system-generated logs is stronger than narrative descriptions. Provide a sampled release packet that shows SCM protections, CI run logs, integrity checks, artifact signing/verification, and release approval records. ¹

We can’t make builds fully reproducible. Can we still meet SR-9(1)?

Yes. Focus on integrity controls you can enforce now: hardened build environments, strong access controls, signed artifacts, dependency verification, and immutable artifact storage, then document limitations and compensating controls in your exception register. ¹

Footnotes

1. NIST SP 800-53 Rev. 5 OSCAL JSON

2. NIST SP 800-53 Rev. 5