fastlike
Trigger and scope
Trigger on: Fastly Compute, Compute@Edge, WASM on Fastly, fastlike, XQD ABI, Compute request lifecycle, 508 loop detection, backend subrequests, body streaming, embedding a Fastly Compute runtime in Go code, or any question about how Compute platform primitives work internally (caching, KV stores, edge rate limiting, ACLs, geolocation, secret stores, config stores, dictionaries, logging, dynamic backends, request collapsing, async I/O).
Do NOT use for: Fastly VCL (use falco), Fastly CLI/API (use fastly-cli or fastly), Viceroy, CDN comparison, WAF, Terraform, cache purging via API, or Fastly logging/stats configuration.
Fastlike — Local Compute Runtime & Reference
Fastlike is a Go implementation of the Fastly Compute ABI. It runs compiled WebAssembly programs locally, implementing the same 249+ host functions that Fastly's production Compute platform provides: backends, dictionaries, KV stores, caching, geolocation, rate limiting, ACLs, secret stores, and more.
Equally important, the fastlike source code is the most complete programmatic specification of how Fastly Compute works — its ABI implementations document every platform primitive, request lifecycle detail, and data structure as executable code.
Fastlike documentation: https://github.com/avidal/fastlike
Source Code as Compute Reference
When you have access to the fastlike source code locally (default: ~/src/fastlike), use these paths to answer specific Compute questions:
More from fastly/fastly-agent-toolkit
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47viceroy
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45fastly-cli
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43xvcl
Extends Fastly VCL with loops, functions, constants, macros, conditionals, and includes via XVCL — a VCL transpiler that compiles .xvcl files into standard VCL. Use when writing VCL for Fastly, working with .xvcl files, generating repetitive VCL (multiple backends, routing rules, headers) with loops, defining reusable VCL functions with return values, using compile-time constants instead of magic numbers, or writing any Fastly VCL configuration. XVCL syntax is not in training data so this skill is required. Also applies when writing and testing VCL locally (compile with `uvx xvcl`, test with falco), reducing VCL code duplication, splitting large VCL into modular includes, or doing any VCL development task for Fastly — even without explicitly mentioning XVCL.
24fastly-ngwaf
Performs an internal audit of Fastly Next-Gen WAF (NGWAF) workspaces to audit that critical templated protection rules are configured and enabled. Use when auditing NGWAF workspace security posture, checking for missing or disabled login protection rules (LOGINDISCOVERY, LOGINATTEMPT, LOGINSUCCESS, LOGINFAILURE), auditing credit card validation rules (CC-VAL-ATTEMPT, CC-VAL-FAILURE, CC-VAL-SUCCESS), auditing gift card protection rules (GC-VAL-ATTEMPT, GC-VAL-FAILURE, GC-VAL-SUCCESS), or identifying potential login endpoints not covered by NGWAF rules.
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