ECC/skills/latency-critical-systems/SKILL.md
Samarjeet Singh Tomar 754b8dd76c
fix: make the installer runtime pass strict supply-chain vetting (#2503)
* fix: make the installer runtime pass strict supply-chain vetting

Remediate the four enterprise supply-chain vetting blockers from
affaan-m/ECC#2502 so the installer runtime (package.json + manifests +
scripts/lib/**) passes strict exact-pin evidence policy:

1. Remove the package.json `postinstall` lifecycle script (it only echoed a
   post-install banner) and move that banner to an explicit opt-in
   `npm run welcome` command. No install-time lifecycle script remains.
2. Exact-pin every dependency in package.json (dependencies + devDependencies)
   to the versions already resolved in package-lock.json; no ^/~ ranges.
3. Replace non-ASCII characters on the installer runtime script/config surface:
   em-dashes (U+2014) in scripts/lib/{path-safety,install-executor,
   install/link-rewrite}.js comments and the two "Itô" (U+00F4) occurrences in
   manifests/{install-components,install-modules}.json descriptions become
   ASCII, so strict-surface Unicode scanners are clean.
4. Drop the bare `require("ajv")` from scripts/lib/install-state.js; the file
   already carries a complete hand-rolled validator enforcing the same
   schemas/install-state.schema.json (ecc.install.v1) constraints, so the
   installer closure is dependency-free (zero non-builtin bare requires).

Refs affaan-m/ECC#2502

* fix: avoid unpinned welcome invocations

Signed-off-by: Samar Tomar <samar_tomar@hotmail.com>

* fix: validate translated skill frontmatter

Signed-off-by: Samar Tomar <samar_tomar@hotmail.com>

* fix: repair skill frontmatter YAML

Signed-off-by: Samar Tomar <samar_tomar@hotmail.com>

* fix: add MIT license to core skill manifests; pin verification-loop tsc invocation

* fix: preserve tsc/pyright exit status in verification-loop type-check (set -o pipefail)

* chore(deps): sync lockfiles with exact-pinned package.json

Regenerate package-lock.json and yarn.lock so the pinned dependency
specs are reflected in both lockfiles. npm ci and Yarn's --immutable
install now pass the sync check. The resolution tree is unchanged
(231 yarn resolutions, byte-identical set; zero npm transitive drift);
only the root descriptor strings move from ranges to the versions
already resolved in the committed lockfiles.

Addresses the Codex P1 on #2503.

---------

Signed-off-by: Samar Tomar <samar_tomar@hotmail.com>
Co-authored-by: Samarjeet Singh Tomar <samartomar@gmail.com>
2026-07-17 17:13:49 -04:00

2.3 KiB

name description license metadata tools
latency-critical-systems Use for latency-sensitive systems such as realtime dashboards, market data, streaming agents, execution gateways, queues, caches, or HFT-like infrastructure where freshness and p95 latency matter. MIT
origin
ECC
Read, Write, Edit, Bash, Grep, Glob

Latency Critical Systems

Use this skill when the user cares about realtime behavior, hot paths, streaming freshness, or execution speed. This includes HFT-like infrastructure, but the skill is engineering-focused. It does not authorize live trading or financial advice.

Split The Metrics

Do not collapse everything into "fast." Track:

  • p50, p95, and p99 latency;
  • throughput;
  • freshness age;
  • queue depth;
  • cache hit rate;
  • provider/API response time;
  • browser render time;
  • correctness under load;
  • failure and retry behavior.

Map The Hot Path

Write the path from user/event to final visible state:

source event -> provider API -> ingest worker -> queue -> cache -> edge route
-> client stream -> browser render -> user-visible state

Then measure each segment separately.

Optimization Order

  1. Remove unnecessary round trips.
  2. Cache stable reads with freshness metadata.
  3. Batch small calls and writes.
  4. Move compute closer to the data or the user.
  5. Split hot and cold paths.
  6. Apply backpressure before queues grow unbounded.
  7. Use streaming only when it improves freshness or user experience.
  8. Add canaries for stale data, degraded providers, and bad cache state.

Verification

Use live readbacks when a deployed surface exists:

  • HTTP timing and response headers;
  • provider freshness timestamp;
  • queue or job state;
  • edge/cache state;
  • browser verification for actual UI freshness;
  • logs around retries and degraded mode.

For market-data or execution-adjacent paths, also verify orderbook age, VWAP assumptions, provider status, and kill-switch behavior before calling the path ready.

Guardrails

  • Do not optimize latency by dropping required validation.
  • Do not hide stale data behind fast cache hits.
  • Do not claim millisecond behavior from client labels without measurement.
  • Do not run live orders, destructive migrations, or customer-impacting deploys without an explicit approval gate.
  • Keep secrets and private payloads out of logs and benchmark artifacts.