perch vs Snyk DeepCode AI

The core split is curated detection versus authored rules. Snyk DeepCode AI pairs symbolic analysis with ML models fine-tuned on security context and a knowledge base built on 25M+ data flow cases across 19+ languages. It also runs real-time in IDEs, CLI, CI/CD, and source managers, and Snyk Secrets catches hardcoded credentials before commit. Priority-setting is where Snyk is strongest: context-aware risk scoring weighs package popularity, code reachability, and exploit maturity so developers chase exploitable flaws rather than every alert. Agent Fix generates autofixes at 85% advertised accuracy, and Snyk cites an 84%-or-greater reduction in mean time to remediate. DeepCode AI Search lets you write custom queries with autocomplete, then test, run, and save them.

Perch inverts the model. You install it globally and run perch scan to find defects and security issues, then write your own rules in perch.yaml using --ensure plain-language guarantees, scoped by --each method or --each file and --where "src/**/*.ts". Findings carry rule ID, file:line, severity, confidence percentage (91%, 78%), and method name. It filters to one rule with --filter rule=<name>, tests against a symbol with perch check <file>::<method>, scans only changed files with --since origin/main, and fails CI on breaking findings via exit code 3. Detections include off-by-one loop errors, weak cryptography like MD5-hashed tokens, and unhandled nulls. It integrates with GitHub Actions, Claude Code, Codex, and Cursor. Snyk gives you breadth and remediation; Perch gives you repository-specific precision and no vendor rule pack.

Snyk DeepCode AI is freemium on paper but the buy decision is an Enterprise Platform Subscription. Evo Continuous Offensive Security and coding-agent security are not available on Free or Team — Snyk requires the Enterprise tier for those. Team also caps at 10 developers, 100 projects, and 1,000 Snyk Code tests per month, which is tight for small teams running SAST across many repos. Enterprise pricing is credit-based and scales with active contributors rather than findings, so cost grows with headcount even if your finding volume drops. That structure rewards organizations already running Snyk for SCA or container scanning, since SAST and autofix land in a platform they already pay for, and it favors open-source maintainers applying for no-cost platform access.

Perch is free. The real cost is engineering time: value depends entirely on writing perch.yaml rules, and there is no hosted dashboard, multi-user policy management, or org-wide analytics. There is also no documented REST API or SDK to trigger scans programmatically, and no GUI for non-technical stakeholders. You also need to be comfortable sending relevant source to a third-party service for analysis. For a small team or solo developer, the comparison is stark: Snyk charges recurring platform fees that scale with contributors; Perch charges zero dollars and some rule-writing hours. Decide whether your bottleneck is detection breadth and autofix (pay Snyk) or enforcement of rules only your team knows (use Perch).