---
id: TASK-009
title: 'TUI: Hash-seeded poll jitter on startup'
status: To Do
assignee: []
created_date: '2026-06-12 04:21'
labels:
  - tui
  - enhancement
dependencies: []
priority: medium
ordinal: 9000
---

## Description

<!-- SECTION:DESCRIPTION:BEGIN -->
All sources currently refresh simultaneously at t=0 on every startup and every 30s interval, causing a thundering herd against the Next.js API. Add deterministic per-source jitter so each source's first fetch is offset by `hash(source_kind) % MAX_JITTER_MS` milliseconds. The offset should be stable across restarts (same source = same offset), so phase relationships don't change between runs.

Implementation sketch:
- Write a `_jitter(kind: str, max_ms: int = 8000) -> float` function using `hashlib.md5(kind.encode()).digest()` as seed
- In `on_mount`, instead of `self.set_interval(REFRESH_SECS, self.refresh_data)`, fire each source's first refresh after its individual jitter offset via `self.set_timer(jitter_secs, lambda: ...)` then start the repeating interval
- Or: a single interval timer that checks per-source "next due" timestamps rather than refreshing everything at once
<!-- SECTION:DESCRIPTION:END -->

## Acceptance Criteria
<!-- AC:BEGIN -->
- [ ] #1 Restarting the TUI does not cause all API calls to fire at the same instant
- [ ] #2 Same source always gets the same jitter offset across restarts
- [ ] #3 Max jitter is configurable via a constant at the top of the file
- [ ] #4 Overall data refresh still completes within REFRESH_SECS of startup
<!-- AC:END -->