Zone A - General Arrangement

Approved

Rev 1.0

Confidential

Murmly

DWG NO. MRM-2026-001
Scale: NTS

Units: Metric

AI Speech-to-Text System

macOS Menu Bar Application · Tauri v2 + React + Rust
BYOK Architecture · Zero Telemetry · Ephemeral Audio

<15s

End-to-End Latency

95%+

Transcription Accuracy

<15MB

Bundle Size

Zone B — System Schematic

Signal Flow Diagram

REF: MRM-SCH-001 · All Connections Active

AUDIO IN cpal/mic

WAV ENCODER hound

API ROUTER reqwest

DEEPGRAM Nova-2

OPENAI GPT-4o

Transcribe Via

DEEPGRAM Nova-2

OPENAI GPT-4o

TEXT OUT result

PROMPT ENGINE GPT-4o-mini

FINAL OUTPUT clipboard

NOTE: Audio data is ephemeral. WAV files deleted immediately after API transmission. No persistent storage.

Zone C — Performance Specifications

Engineering Specification Sheet

DOCUMENT: MRM-SPEC-001 · All Values Nominal

#	Parameter	Specification	Tolerance	Status
01	End-to-End Latency	15s (3min audio)	±2s	PASS
02	Transcription Accuracy	>95%	±3%	PASS
03	Cost per Minute	$0.0043	Variable	NOMINAL
04	Bundle Size	<15MB	—	PASS
05	Cold Start Time	<200ms	±50ms	PASS
06	Recording Start	<100ms	±20ms	PASS
07	Memory Usage	<200MB	—	PASS
08	Telemetry Data	ZERO	ABSOLUTE	ENFORCED

Zone D — Provider Analysis

Parallel Circuit Paths

Select provider based on resistance (cost) and throughput (features)

Deepgram NOVA-2

Resistance (cost) $0.0043/min

Throughput (accuracy) HIGH

Latency FAST

Streaming SUPPORTED

RECOMMENDED: COST-OPTIMIZED PATH

OPENAI GPT-4O AUDIO

RESISTANCE (cost) $0.006/min

THROUGHPUT (accuracy) VERY HIGH

LATENCY MODERATE

TRANSFORM BUILT-IN

RECOMMENDED: FEATURE-RICH PATH

Zone E — Components

Bill of Materials

BOM REF: MRM-BOM-001 · All Components Required

#	COMPONENT	DESCRIPTION	QTY	MATERIAL
M-001	Recording Engine	Real-time audio capture & WAV encoding	1	cpal + hound (Rust)
M-002	Transcription API	Cloud AI speech-to-text processing	2	OpenAI / Deepgram
M-003	Prompt Engine	Text transformation & cleanup	1	GPT-4o-mini
M-004	Security Module	API key storage & retrieval	1	macOS Keychain
M-005	Runtime Shell	Native macOS application wrapper	1	Tauri v2
M-006	Interface Layer	User interface rendering engine	1	React 19 + TypeScript
M-007	Async Runtime	Non-blocking I/O & task scheduling	1	Tokio (Rust)
M-008	HTTP Client	API communication layer	1	reqwest (Rust)

Zone F — Procedures

Assembly Instructions

Procedure: MRM-ASM-001 · Follow in sequence

01

INSTALL APPLICATION

Download .dmg and drag Murmly.app to /Applications. Bundle includes all dependencies. No homebrew, no CLI, no prerequisites.

est. 30 seconds

02

CONFIGURE API KEYS

Open Preferences panel. Enter your OpenAI or Deepgram API key. Credentials stored securely in macOS Keychain — never written to disk.

BYOK required

03

ACTIVATE RECORDING

Click the menu bar icon or use the global shortcut. Recording begins in <100ms. Audio level indicator confirms capture.

<100ms activation

04

RECEIVE TRANSCRIPTION

Stop recording. Audio is encoded to WAV, transmitted to your chosen API, transcribed, and (optionally) transformed via prompt. Result copied to clipboard.

auto-processed

CAUTION: This application collects ZERO analytics, ZERO telemetry, and maintains ZERO persistent history. All audio data is destroyed immediately after transcription. Your API keys never leave your machine's Keychain.

Zone G - Deployment

APP COST: $0.00 · API USAGE: ~ $0.006/min

Ready for Deployment

Zero-cost application. Bring your own API key.
Pay only for what you transcribe.

macOS 12+ REQUIRED · APPLE SILICON + INTEL