LedgerLine/docs/roadmap/summary.md

Roadmap summary — all phases at a glance

Part of docs/roadmap/ — the one-page overview. Read intro.md first for platform/background context; read the individual phase-N.md file for the phase you're actually working on. This file exists so an agent (or you) can check overall status and sequencing without loading every phase's full detail.

Twelve phases (0 through 11 — Phase 0 has two halves, 0a and 0b). Each phase file follows the same shape: Status, Message (what's done, notes, warnings), Time-box, Concepts, Resources, Build, Done when.

Status and focus

Phase	File	Status	Focus	Time-box	Main output
0a	phase-0.md	Done	Integration test suite (agent, tests only)	1 evening	Red suite + RED-BASELINE.md
0b	phase-0.md	Done	Base project implemented to green (second agent)	1–2 evenings	Ledgerline running, list of frustrations
1	phase-1.md	Done	Deployment: Compose + Traefik on a server	1 evening	https://ledgerline.vione.cloud
2	phase-2.md	Done	Concepts + first trace	1 evening	One trace in Tempo
3	phase-3.md	In progress	Distributed tracing	2–3 evenings	Connected trace across 7 services incl. the async hop
4	phase-4.md	Not started	Structured logs	1–2 evenings	Two-way trace↔log correlation
5	phase-5.md	Not started	Metrics	2 evenings	RED per service, service map, exemplars
6	phase-6.md	Not started	Dashboards as code	2 evenings	kubectl apply -k k8s/ restores all dashboards
7	phase-7.md	Not started	k6 + percentiles	1–2 evenings	Baseline vs degraded load profiles
8	phase-8.md	Not started	SLO / error budget / RTO / RPO	1–2 evenings	docs/SLO.md + burn-rate alerts
9	phase-9.md	Not started	Bottleneck hunting	2 evenings	docs/INVESTIGATION.md
10	phase-10.md	Not started	Filebeat / Logstash / OTel judgment	1–2 evenings	docs/PIPELINE-CHOICES.md
11	phase-11.md	Not started	Delivery	1 evening	README + rehearsed demo

What each phase is, in one line

• 0 — Build the base project, test-first. Write the black-box test suite, then implement the seven-service system against it as a frozen contract. Done — see phase-0.md for the full implementation report.
• 1 — Deployment. Put Ledgerline on a server with Docker Compose behind Traefik and a Let's Encrypt certificate, served at a real domain. Plumbing only — no telemetry, no app changes. Done — see phase-1.md.
• 2 — The model, and one signal end to end. Learn the OTel API/SDK/Collector split and the M.E.L.T. vocabulary; deploy the real Grafana-stack platform (the mentor's Ansible stack, ported to k3s as k8s/ — already deployed on falken) and get one auto-instrumented trace into Tempo. Done — see phase-2.md for what carries forward.
• 3 — Distributed tracing. The heart of the task: auto- and manual-instrument all seven services, and hand-propagate trace context across the Redis Stream hop, which carries none by default.
• 4 — Structured logs, correlated to traces. Replace prose logging with structured events carrying a lowercase trace_id, so Loki and Tempo link in both directions.
• 5 — Metrics. Instrument RED metrics per service, understand cardinality limits, and route app metrics to Prometheus given Alloy rejects OTLP metrics (404 on /v1/metrics). Tempo's metrics-generator already produces span metrics and the service graph — don't duplicate it in the collector.
• 6 — Dashboards and alerts as code. Generate dashboard JSON with the Grafana Foundation SDK and ship it with the platform (k8s/grafana/), so "destroy and recreate in seconds" is a real, repeatable command.
• 7 — Load testing with k6, and percentiles. Learn why percentiles can't be averaged, what coordinated omission is, and drive Ledgerline with arrival-rate executors to get a clean before/after load profile.
• 8 — SLI, SLO, SLA, error budgets, RTO, RPO. Define Ledgerline's SLIs and SLOs from the Phase 7 baseline (not from thin air), write an error-budget policy, and wire multi-burn-rate alerts.
• 9 — Bottleneck hunting (the capstone). Given a random, undisclosed set of chaos flags, find the pathologies from telemetry alone using a top-down, hypothesis-driven method, and write it up as an incident doc.
• 10 — Tool-selection judgment. Reason through Filebeat vs Logstash vs OpenTelemetry on six concrete axes, using the platform's real second stack (Filebeat → Logstash → Elasticsearch → Kibana) as the counterpoint.
• 11 — Package the delivery. README, a rehearsed five-minute demo, the written deliverables (SLO.md, PIPELINE-CHOICES.md, INVESTIGATION.md, CONCEPTS.md), and an honest "what I'd do differently in production" section.

If you have to cut scope

Cut Phase 10's build (keep the writing) and Phase 7's soak test first. Do not cut Phase 9 — it's the only phase that proves you learned anything.