OccamO

CI-native complexity and performance regression detection with SARIF and policy-based gates.

2025 - Present

  • Python
  • TypeScript
  • Docker

OccamO focuses on one practical outcome: detect only what got worse in a pull request and make that signal actionable in the same CI context where teams already work.

OccamO architecture graph showing repository diff analysis, policy gate evaluation, and SARIF plus PR comment outputs.
Architecture graph: OccamO ingests base vs head diffs, computes regression risk, applies policy budgets, and emits GitHub-native feedback.

Problem

Most static analysis tools generate too much noise in pull requests. Teams needed a system that highlights regressions, not generic findings.

Constraints

  • CI runtime had to remain practical for active repositories.
  • Findings had to map clearly to changed functions and base-branch baselines.
  • Outputs needed to integrate with existing workflows (PR comments, check runs, SARIF).

Architecture

  • Baseline diff model comparing base and head snapshots to isolate regressions.
  • Stable function IDs (path, qualified name, normalized body hash) for robust cross-branch matching.
  • Multi-output adapters (JSON, Markdown, SARIF, annotations, check payloads).
  • Policy-as-code gating for warning/fail thresholds and no-regression paths.

Tradeoffs and Failures

  • Deep analysis increases precision but can raise CI cost on very large pull requests.
  • Polyglot parser support improves coverage but introduces dependency and maintenance overhead.
  • Strict policies reduce drift but can block teams if baseline quality is already poor.

Engineering Impact

  • Shifted performance and complexity governance directly into PR review.
  • Reduced alert fatigue by reporting only worsened signals.
  • Enabled enforceable engineering quality controls through CI gate presets.

Outcomes

  • Actionable regression deltas with before-vs-after context.
  • Native ecosystem integration through SARIF upload and PR feedback.
  • Improved review velocity by combining changed-only mode with policy budgets.

What Made This Approach Different

OccamO is built around comparative signal quality: not “what exists,” but “what degraded.” This baseline-first philosophy drives both architecture and developer experience.