Sizing Estimate


Date	2026-03-21
Method	Architecture-Driven PERT v3
Scope Clarity	B – Partially Defined (60%)
Repos Explored	5 of 7 affected repos
Calibrated From	333 historic stories, 10 comparable epics

Estimate Summary

================================================================
PRD SIZING ESTIMATE (PERT)
Feature: Uncrew Industrial Operations Platform
----------------------------------------------------------------
Stories:                 36
Expected Duration:       167.7 days  (range: 155 - 180, 95% CI)
Weeks:                   33.5
Confidence:              High  (stddev ratio: 0.037)

Expected Cost:           $201,200
Cost Range:              $186,200 - $216,200  (95% CI)
Cost Basis:              $1,200/day fully-loaded
                         ($200k avg salary x 1.4 overhead)

Scope:  B (60%)  |  Stats age: 1d
Method: Architecture-driven PERT v3 -- 5 repos explored
================================================================

Cost Breakdown by Domain

Domain	Stories	Expected Days	Expected Cost
Backend Go (orchestration + dock + missions)	19	91.1d	$109,300
Frontend React	8	38.5d	$46,200
Firmware C++ (pathfinding + mavlink + camera)	3	23.2d	$27,800
Protobuf / API Definitions	4	10.7d	$12,800
Infrastructure + Structural	2	10.0d	$12,000
Totals	36	167.7d	$201,200

Cost basis: $200,000 average annual salary with 1.4x fully-loaded multiplier (benefits, overhead, tools, management) = $280,000 / 230 effective working days = $1,200/day. Adjust the multiplier for your team’s actual overhead.

Story Breakdown

Proto Layer – `uncrew-api-private`

#	Story	Opt	Likely	Pess	Expected	Cost
1	Define orchestration service protos (templates, schedules, dispatch, webhooks)	2d	4d	7d	4.2d	$5,000
2	Define dock status service protos (status, health, adapter interface)	1d	2d	4d	2.2d	$2,600
3	Define data delivery service protos (delivery status, webhook config)	1d	2d	4d	2.2d	$2,600
4	Add camera_objectives + template_ref to mission.proto	1d	2d	4d	2.2d	$2,600

New Orchestration Service – Go + Temporal

#	Story	Opt	Likely	Pess	Expected	Cost
5	Service scaffolding: Go project, Temporal SDK, K8s Helm chart, CI pipeline	3d	5d	10d	5.5d	$6,600
6	Mission template CRUD (Temporal activities + PostgreSQL persistence)	3d	5d	8d	5.2d	$6,200
7	Recurring schedule cron workflows (Temporal cron, blackout windows)	3d	5d	10d	5.5d	$6,600
8	On-demand mission API + priority queuing (urgent vs routine)	2d	4d	8d	4.3d	$5,200
9	Mission dispatch workflow (template resolve, dock check, plan, dispatch)	4d	7d	14d	7.7d	$9,200
10	Webhook dispatch for mission status + data delivery events	2d	3d	6d	3.3d	$4,000
11	Mission failure notification workflow (weather, dock offline, drone unavailable)	2d	3d	6d	3.3d	$4,000
12	OAuth2/API key auth + multi-tenant isolation	2d	4d	8d	4.3d	$5,200
13	Usage metering API (read from existing hubops-core data)	2d	3d	6d	3.3d	$4,000

Dock Management – Go + MQTT (in orchestration service)

#	Story	Opt	Likely	Pess	Expected	Cost
14	Dock adapter interface + MQTT broker integration	3d	5d	10d	5.5d	$6,600
15	Horizon dock adapter implementation (depends on dock protocol docs)	4d	7d	14d	7.7d	$9,200
16	Dock readiness gating as Temporal activity (pre-dispatch check)	1d	2d	5d	2.3d	$2,800
17	Dock health history storage + anomaly alerts	2d	4d	7d	4.2d	$5,000

Missions Service – `uncrew-missions-service`

#	Story	Opt	Likely	Pess	Expected	Cost
18	Add camera_objectives to Mission model + CameraObjective SOP + mission items	3d	6d	10d	6.2d	$7,400
19	Add template_ref to MissionRequest + accept missions from orchestration service	1d	3d	5d	3.0d	$3,600

Pathfinding – `uncrew-pathfinding` (C++)

#	Story	Opt	Likely	Pess	Expected	Cost
20	Camera-objective cost function component (inspect targets, altitude, angles)	4d	7d	14d	7.7d	$9,200

Mavlink Shim – `uncrew-mavlink-shim` (C++)

#	Story	Opt	Likely	Pess	Expected	Cost
21	Gimbal control policy + MAVLink gimbal passthrough commands	5d	8d	16d	8.8d	$10,600

Data Passthrough – `uncrew-uav-camera-capture` + GCP

#	Story	Opt	Likely	Pess	Expected	Cost
22	Data passthrough pipeline: inference results to customer GCS bucket (Cloud Functions)	4d	6d	12d	6.7d	$8,000
23	Data delivery confirmation + retry logic	2d	3d	6d	3.3d	$4,000

Frontend – `uncrew-apollo-frontend`

#	Story	Opt	Likely	Pess	Expected	Cost
24	Mission template builder UI (extend existing POC Mission Planner)	3d	6d	10d	6.2d	$7,400
25	Scheduling UI + calendar view (FullCalendar integration)	4d	7d	12d	7.3d	$8,800
26	Dock status dashboard (map + status list + indicators)	3d	5d	9d	5.3d	$6,400
27	Usage metering dashboard (Recharts, filters, metric cards)	3d	5d	9d	5.3d	$6,400
28	Camera objectives in mission planning UI (angle, altitude, target selection)	2d	4d	8d	4.3d	$5,200
29	Data delivery status in mission detail view + manual retry	1d	2d	5d	2.3d	$2,800
30	Operations calendar view with conflict detection	2d	4d	8d	4.3d	$5,200
31	Usage export (CSV/PDF download + scheduled email)	2d	3d	6d	3.3d	$4,000

Structural Stories

#	Story	Opt	Likely	Pess	Expected	Cost
32	Spike: Investigate Horizon dock protocol + document interface	2d	3d	5d	3.2d	$3,800
33	Spike: Validate HX1 MAVLink gimbal command compatibility	2d	3d	7d	3.5d	$4,200
34	Infrastructure: Temporal Cloud setup + new service K8s namespace + Helm	2d	4d	8d	4.3d	$5,200
35	Cross-service integration testing (orchestration -> missions -> mavlink -> data)	3d	6d	12d	6.5d	$7,800
36	OpenAPI spec + API documentation for customer-facing endpoints	2d	3d	5d	3.2d	$3,800

Architectural Decisions

Decision	Rationale
Temporal Cloud for orchestration + scheduling	Eliminates custom scheduler engine (~15-20d saved). Durable workflows handle crash recovery. Cron workflows are built-in. Go SDK is first-class. Visibility UI comes free.
MQTT for dock communication	Industry standard for IoT telemetry. Horizon dock likely supports it. Push-based (vs polling) reduces latency.
GCP Cloud Functions for data passthrough	Serverless, scales to 100+ sites without infra management. Routes inference results to customer cloud buckets.
FullCalendar (React library) for scheduling UI	Mature open-source calendar component. Saves weeks of custom frontend work.

Architecture Sketch

                        +----------------------------------------------+
                        |     NEW: Orchestration Service (Go)           |
                        |              + Temporal Cloud                 |
  Customer UI --------->|  +-------------+  +------------------+       |
  Customer API -------->|  |  Scheduler   |  | Mission Templates|       |
                        |  | (Temporal    |  | (CRUD, versioned)|       |
                        |  |  cron)       |  +--------+---------+       |
                        |  +------+-------+           |                |
                        |         |                   |                |
                        |  +------v-------------------v------+         |
                        |  |    Mission Dispatch Workflow      |         |
                        |  |  (dock check, queue, priority)   |         |
                        |  +------+---------------------------+         |
                        |         |                                    |
                        |  +------v-----------+                        |
                        |  | Dock Manager     |                        |
                        |  | (MQTT adapter,   |<--- Horizon Dock       |
                        |  |  health history) |     (MQTT)             |
                        |  +-----------------+                         |
                        |                                              |
                        |  +-----------------+                         |
                        |  | Usage Metering  |                         |
                        |  | (read hubops)   |                         |
                        |  +-----------------+                         |
                        +------------------+---------------------------+
                                           | gRPC
                    +----------------------v--------------------------+
                    |      uncrew-missions-service (Go)                |
                    |  + camera_objectives field on Mission            |
                    |  + template_ref field on MissionRequest          |
                    |  + CameraObjective -> CameraSOP -> items         |
                    +------------------+------------------------------+
                                       |
              +------------------------+------------------------+
              v                        v                        v
   uncrew-pathfinding (C++)   mavlink-shim (C++)    uav-camera-capture
   + camera_objective_cost    + gimbal_control      + data passthrough
     function component         policy (new)          to customer cloud
                              + MAVLink gimbal         (GCP Cloud Funcs)
                                passthrough

                    +----------------------------------------------+
                    |     uncrew-apollo-frontend (React)             |
                    |  + Mission Template Builder UI                 |
                    |  + Dock Status Dashboard                      |
                    |  + Scheduling / Calendar View (FullCalendar)  |
                    |  + Usage Metering Dashboard (Recharts)        |
                    |  + Camera objectives in mission planner       |
                    +----------------------------------------------+

                    +----------------------------------------------+
                    |     uncrew-api-private (Protobuf)              |
                    |  + orchestration/v1/ (new domain)              |
                    |  + dock_status/v1/ (new domain)                |
                    |  + data_delivery/v1/ (new domain)              |
                    |  + camera_objectives in mission.proto          |
                    +----------------------------------------------+

Repos Explored

Repo	Tech Stack	Exploration Depth	Key Findings
`uncrew-missions-service`	Go / gRPC / GORM / PostgreSQL	Deep	Objectives -> SOPs -> MissionItems pipeline. Clear extension points for camera_objectives and template_ref.
`uncrew-apollo-frontend`	React 18 / Vite / TypeScript / Zustand	Deep	POC Mission Planner page exists with drag-drop objectives. Mapbox+Deck.gl, Recharts already available.
`uncrew-api-private`	Protobuf / gRPC (multi-language codegen)	Deep	20+ gRPC services. Well-established pattern for adding new service domains.
`uncrew-mavlink-shim`	C++ / MAVSDK / Boost.Asio	Medium	No existing gimbal control code. Camera capture is HTTP-only. Gimbal needs new policy + MAVLink passthrough.
`uncrew-pathfinding`	C++ / Boost / Theta*	Medium	C++ library (not Python as PRD assumed). Composable cost function system. Camera-objective routing = new cost function component.

Comparable Epics (Historic Data)

Epic	Summary	Actual Days	Stories	Relevance
CORE-2552	Uncrew Bundled Deployment (New Service)	166.4d	18	Closest: greenfield Go service with K8s deployment
CORE-2472	AirDEX Ingest (External Integration)	298.5d	23	External integration, multi-repo, streaming data
CORE-2775	Simulator Failure Injection	38.2d	26	Multi-repo (7 repos), firmware + frontend + backend

Historic accuracy note: Across 296 past stories, actuals averaged 4x estimates (median), with only 24% of stories completing within 2x of their estimate. This estimate uses PERT with conservative pessimistic values to account for this pattern. The 95% CI range of 155-180 days represents the statistical spread, but systemic risks (undocumented dock protocol, untested gimbal compatibility, Temporal learning curve) could push actual duration toward the comparable epic range of 166-298 days.

Risk Flags

Flag	Source	Impact
`hard_repo_mavlink`	Detected (mavlink-shim in scope)	Gimbal work is specialized C++ with no existing code to build on
`new_service`	PRD input	Greenfield orchestration service is the largest single work item
`external_integration`	PRD input	Horizon dock protocol undocumented; HX1 gimbal compatibility untested
`multi_repo`	PRD input	7 repos affected; coordination overhead
`api_design`	PRD input	New REST + gRPC APIs require contract-first design
`infrastructure`	PRD input	Temporal Cloud, new K8s namespace, MQTT broker

Phase Mapping

The PRD defines three phases. Here is how stories map:

Phase 0: Discovery (Stories 32-33) – ~6.7 days / $8,000

Spike: Horizon dock protocol investigation
Spike: HX1 MAVLink gimbal compatibility

Phase 1: MVP (Stories 1-19, 22-27, 34-36) – ~131.5 days / $157,800

Proto definitions (all)
Orchestration service (scaffolding, templates, scheduling, dispatch, auth)
Dock management (adapter, Horizon implementation, readiness gating)
Missions service changes (camera objectives, template ref)
Data passthrough pipeline + confirmation
Frontend: template builder, scheduling UI, dock dashboard, metering dashboard
Infrastructure + integration testing + documentation

Phase 1.1 / Phase 2: Full Vision (Stories 20-21, 28-31) – ~29.5 days / $35,400

Camera-objective cost function (pathfinding, C++)
Gimbal control policy (mavlink-shim, C++)
Camera objectives in mission planning UI
Data delivery status UI
Operations calendar with conflict detection
Usage export (CSV/PDF)

Last updated on May 11, 2026