docs: update ARCHITECTURE.md for v0.6.0 gene mutation system

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thakares committed 2026-05-29 15:55:33 +05:30
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@@ -1,6 +1,6 @@
# ChronoSeal — Architecture
> Note (v0.6.0): Synthetic Gene Mutation flow and mutation handshake updates are documented in [REFRACTORING-v0.6.0.md](REFRACTORING-v0.6.0.md) and [API.md](API.md).
> Note (v0.6.0): Synthetic Gene Mutation flow and mutation handshake updates are documented in [REFRACTORING-v0.6.0.md](https://github.com/thakares/chronoseal-rs/blob/main/docs/REFRACTORING-v0.6.0.md) and [API.md](https://github.com/thakares/chronoseal-rs/blob/main/docs/API.md).
## Overview
@@ -23,8 +23,7 @@ is stored in SQLite keyed on `session_id`. Every HTTP request is independently
verifiable.
**Silent failure.** Validation failures never return an error status or an
error body. The server always responds `{"status":"ok"}` and simply omits
`next_salt`. The client degrades gracefully. Attackers cannot enumerate
error body. The server always responds `{"status":"ok"}` and simply omits `next_salt`. The client degrades gracefully. Attackers cannot enumerate
validation rules by probing error responses.
**Private key isolation.** The Ed25519 signing key is generated inside the
@@ -41,19 +40,25 @@ activity, correct WASM execution, chain state synchronisation, and a valid
Ed25519 signature over a time-windowed payload. For an automated client, the
synchronisation burden alone makes scaled operation expensive.
**Deterministic mutation parity (v0.6.0).** Each heartbeat additionally carries
a `mutation_step` and `gene_commitment` derived from a server-issued mutation
program. Server and WASM execute the same shared opcode engine
(`shared/src/vm_extensions.rs`), and the server rejects any heartbeat where
the recomputed commitment does not match the client-supplied value.
### High-Level Design
- **Core**: Rust + Axum (async web framework)
- **Storage**: `db_type` selectable (`sqlite-in-memory`, `sqlite-in-disk`, `valkey` compatibility mode)
- **Client**: WASM + Rust (runs in browser for proof generation)
- **Security Model**: Behavioral analysis + hash chaining + entropy scoring
- **Security Model**: Behavioral analysis + hash chaining + entropy scoring + deterministic gene mutation parity
- **Deployment**: Static musl binary, systemd service, optional Docker
### Key Components
- `shared/` — Types, constants, crypto primitives used by server and WASM
- `shared/` — Types, constants, crypto primitives, gene model, and mutation engine used by server and WASM
- `server/` — Axum routes, session management, trust engine, rate limiting, cleanup tasks
- `wasm/` — Client-side proof generation
- `wasm/` — Client-side proof generation, mutation preview/commit lifecycle
- `frontend/` — Static assets served by the application
### Unix-Native Design Decisions
@@ -62,12 +67,11 @@ synchronisation burden alone makes scaled operation expensive.
- All state is either in-memory or in standard locations (`/run/`, `/var/log/`, `/etc/`)
- Graceful shutdown and reload support via signals
- Logging designed for `journalctl` and structured parsing
- Configuration will be fully runtime (no recompile needed)
- Configuration is fully runtime (no recompile needed)
### Design Goal
ChronoSeal should feel as natural to use as `nginx` or `redis-server` on a Linux system.
---
## ChronoSeal should feel as natural to use as `nginx` or `redis-server` on a Linux system.
## Component Map
@@ -89,7 +93,10 @@ ChronoSeal should feel as natural to use as `nginx` or `redis-server` on a Linux
│ │ ├ generate_keypair() │ │
│ │ ├ sign_message() │ │
│ │ ├ compute_next_hash() │ │
│ │ └ run_program() │ │
│ │ ├ run_program() │ │
│ │ vm_extensions.rs │ │
│ │ ├ preview_mutation() │ │
│ │ └ commit_mutation() │ │
│ └──────────────────────────────┘ │
└─────────────────────────────────────────────────────────┘
│ HTTPS
@@ -103,6 +110,7 @@ ChronoSeal should feel as natural to use as `nginx` or `redis-server` on a Linux
│ session.rs │
│ ├ create_session() │
│ └ verify_heartbeat() │
│ └ validate_mutation_parity() [v0.6.0] │
│ │ │
│ ┌──────────┼──────────────┐ │
│ ▼ ▼ ▼ │
@@ -112,9 +120,11 @@ ChronoSeal should feel as natural to use as `nginx` or `redis-server` on a Linux
│ │ │
│ ▼ │
│ shared::hashing (Blake3 hash chain) │
│ shared::gene (gene model + commitment) [v0.6.0] │
│ shared::vm_extensions (mutation opcodes) [v0.6.0] │
│ │ │
│ ▼ │
│ storage.rs (in-memory SQLite) │
│ storage.rs (SQLite: in-memory / in-disk / valkey) │
│ │
│ ratelimit.rs cleanup.rs vm.rs middleware.rs │
└─────────────────────────────────────────────────────────┘
@@ -137,14 +147,20 @@ Client Server
│ │ salt₀ = rand::random::<[u8;16]>()
│ │ H(0) = Blake3(session_id║pub_key║salt₀)
│ │ opcodes = generate_random_program(8..=16)
│ │ gene = initial gene buffer [v0.6.0]
│ │ mutation_order = generate_mutation_program() [v0.6.0]
│ │ INSERT INTO sessions …
│ │
│◄── { session_id, salt, opcodes_b64, │
│ initial_hash, expires_at } ───────┤
│ initial_hash, expires_at, │
│ mutation_step, │ [v0.6.0]
│ mutation_order_b64 } ─────────────┤ [v0.6.0]
│ │
│ prevHash = initial_hash │
│ currentSalt = salt │
│ opcodesB64 = opcodes_b64 │
│ prevHash = initial_hash │
│ currentSalt = salt │
│ opcodesB64 = opcodes_b64 │
│ mutationStep = mutation_step │ [v0.6.0]
│ mutationOrderB64 = mutation_order_b64 │ [v0.6.0]
```
### 2. Heartbeat — `POST /hb`
@@ -154,21 +170,25 @@ Fired every 12–25 seconds with uniform random jitter.
```
Client Server
│ │
│ stackState = run_program(opcodesB64) │
│ events = collectEntropy(lastTime) │
│ ts = Date.now() │
│ stackState = run_program(opcodesB64) │
│ commitment = preview_mutation( │ [v0.6.0]
│ mutationOrderB64, mutationStep) │
│ events = collectEntropy(lastTime)│
│ ts = Date.now() │
│ │
│ signable = { │
│ entropyData, fingerprint, │ ← keys sorted alphabetically
│ prevHash, sessionId, │
│ stackState, timestamp │
│ stackState, timestamp, │
│ mutation_step, gene_commitment │ [v0.6.0]
│ } │
│ sig = sign_message( │
│ JSON.stringify(signable, keys.sort))│
│ │
├─── { session_id, prev_hash, timestamp, │
│ entropy_data, stack_state, │
│ fingerprint, signature } ────────►│
│ fingerprint, signature, │
│ mutation_step, gene_commitment }─►│ [v0.6.0]
│ │ 1. Rate limit check
│ │ 2. Lookup session, check expiry
│ │ 3. Verify Ed25519 signature
@@ -176,22 +196,28 @@ Client Server
│ │ 5. Validate timestamp window ±30s
│ │ 6. Validate mouse behavior
│ │ 7. Validate fingerprint signals
│ │ 8. Compute H(n), rotate salt
│ │ 9. UPDATE sessions …
│ │ 8. Validate mutation step parity [v0.6.0]
│ │ 9. Validate gene commitment [v0.6.0]
│ │ 10. Compute H(n), rotate salt
│ │ 11. Advance gene state [v0.6.0]
│ │ 12. UPDATE sessions …
│ │
│◄── { status: "ok", next_salt } ────────┤
│◄── { status: "ok", next_salt, │
│ next_mutation_step, │ [v0.6.0]
│ next_mutation_order_b64 } ────────┤ [v0.6.0]
│ │
│ sentSalt = currentSalt ◄── captured BEFORE rotation
│ currentSalt = next_salt │
│ prevHash = compute_next_hash( │
│ sentSalt = currentSalt ◄── captured BEFORE rotation
│ currentSalt = next_salt │
│ mutationStep = next_mutation_step │ [v0.6.0]
│ mutationOrderB64 = next_mutation_order_b64 [v0.6.0]
│ prevHash = compute_next_hash( │
│ prevHash, ts, entropy, │
│ stackState, sentSalt) │
```
### 3. Failure Path
On any validation failure the server returns `{"status":"ok"}` with no
`next_salt`. The client logs a warning and continues scheduling heartbeats.
On any validation failure the server returns `{"status":"ok"}` with no `next_salt`. The client logs a warning and continues scheduling heartbeats.
The chain is broken — subsequent heartbeats will also fail silently.
No error is surfaced to the page or its visitors.
@@ -224,19 +250,40 @@ H(n) = Blake3(
Salt rotation means an attacker who intercepts a heartbeat cannot compute
future chain links without also intercepting every subsequent server response.
### Gene Commitment (v0.6.0)
A domain-separated BLAKE3 commitment binds both the gene buffer and the sorted
environment records into a single 32-byte value that is included in the signed
heartbeat payload and validated server-side:
```
gene_commitment = BLAKE3(
"chronoseal/gene/v1" ← domain separator
║ gene_bytes ← Vec<u8> gene buffer
║ for each (symbol, qty) sorted by symbol:
symbol_u16_le ║ qty_u32_le
)
```
The server recomputes the candidate gene state from its authoritative
`pending_mutation` program and rejects any heartbeat where
`recomputed_commitment != client_gene_commitment`.
### Canonical Signing Payload
The signed message is a JSON object with top-level keys sorted alphabetically,
serialised with no extra whitespace:
```json
```
{
"entropyData": { "events": [{"t":…,"x":…,"y":…}] },
"fingerprint": { "aspectRatio":"…","devicePixelRatio":"…","hardwareConcurrency":… },
"prevHash": "hex…",
"sessionId": "hex…",
"stackState": { "ip":…,"stack":[…] },
"timestamp": 1234567890123
"entropyData": { "events": [{"t":…,"x":…,"y":…}] },
"fingerprint": { "aspectRatio":"…","devicePixelRatio":"…","hardwareConcurrency":… },
"gene_commitment": "hex…",
"mutation_step": N,
"prevHash": "hex…",
"sessionId": "hex…",
"stackState": { "ip":…,"stack":[…] },
"timestamp": 1234567890123
}
```
@@ -247,8 +294,8 @@ key order difference, or whitespace difference causes a signature failure.
### Hashing Algorithm
Blake3 is used throughout: hash chain links, entropy data digest, stack state
digest, and the VM HASH opcode. Blake3 is chosen for speed in WASM,
resistance to length-extension attacks, and a clean Rust API.
digest, gene commitment, and the VM HASH opcode. Blake3 is chosen for speed
in WASM, resistance to length-extension attacks, and a clean Rust API.
---
@@ -259,24 +306,51 @@ on every heartbeat and includes the resulting `StackState { stack, ip }` in
the signed payload. This ensures each heartbeat carries unique, verifiable
computation without additional round-trips.
### Instruction Set
### Core Instruction Set
| Opcode | Mnemonic | Operand | Stack effect | Description |
|--------|----------|---------------|--------------|-------------|
| `0x00` | PUSH | u32 (4B LE) | +1 | Push literal |
| `0x01` | ADD | — | −1 | `a + b` wrapping |
| `0x02` | SUB | — | −1 | `a - b` wrapping |
| `0x03` | MUL | — | −1 | `a * b` wrapping |
| `0x04` | XOR | — | −1 | `a ^ b` |
| `0x05` | AND | — | −1 | `a & b` |
| `0x06` | OR | — | −1 | `a \| b` |
| `0x07` | ROT | — | −1 | `a.rotate_left(b % 32)` |
| `0x08` | NOT | — | 0 | `!a` (unary) |
| `0x09` | HASH | — | -(depth-1) | Blake3 of all stack items → single u32 |
| Opcode | Mnemonic | Operand | Stack effect | Description |
| ------ | -------- | ----------- | ------------ | -------------------------------------- |
| `0x00` | PUSH | u32 (4B LE) | +1 | Push literal |
| `0x01` | ADD | — | −1 | `a + b` wrapping |
| `0x02` | SUB | — | −1 | `a - b` wrapping |
| `0x03` | MUL | — | −1 | `a * b` wrapping |
| `0x04` | XOR | — | −1 | `a ^ b` |
| `0x05` | AND | — | −1 | `a & b` |
| `0x06` | OR | — | −1 | `a \| b` |
| `0x07` | ROT | — | −1 | `a.rotate_left(b % 32)` |
| `0x08` | NOT | — | 0 | `!a` (unary) |
| `0x09` | HASH | — | -(depth-1) | Blake3 of all stack items → single u32 |
The generator ensures ≥ 2 items on the stack before any binary opcode.
NOT (0x08) does not change depth. HASH resets depth to 1.
### Mutation Opcodes (v0.6.0)
The gene mutation extension operates on a separate `Vec<u8>` gene buffer and a
bounded environment map `Vec<(u16 symbol, u32 quantity)>`. These opcodes are
defined in `shared/src/vm_extensions.rs` and executed identically by both
server and WASM to guarantee deterministic parity.
| Opcode | Mnemonic | Effect |
| ------ | ------------------ | ------------------------------------------------------------- |
| `0x23` | GENE_LOAD | Push `gene[idx]` onto the stack |
| `0x24` | GENE_STORE | Pop stack top and store at `gene[idx]` |
| `0x25` | MUTATE_POINT | Apply wrapping byte delta at index |
| `0x26` | INSERT | Insert popped byte at index |
| `0x27` | DELETE | Delete byte at index and push the removed value |
| `0x28` | TRANSCRIBE | Push deterministic transcription hash of current gene state |
| `0x29` | APPLY_MUTAGEN | Mix environment symbol quantity into gene byte at index |
| `0x2A` | FINALIZE_GENE_HASH | Push commitment-derived `u32` onto the stack |
| `0x2B` | CONSUME | Pop amount, subtract from environment symbol quantity |
| `0x2C` | PRODUCE | Pop amount, add to environment symbol quantity |
**Constraints enforced at runtime:**
- Mutation program length capped at `MAX_MUTATION_PROGRAM_BYTES`
- Environment record count capped at `MAX_ENV_RECORDS`
- Environment records validated for sortedness, uniqueness, non-zero quantity
- Stack underflow and unknown opcodes cause deterministic, symmetric failures on both server and WASM paths
---
## Behavioral Validation
@@ -286,20 +360,20 @@ NOT (0x08) does not change depth. HASH resets depth to 1.
Every heartbeat includes the mouse events collected since the previous
heartbeat. Server checks:
| Check | Threshold |
|---|---|
| Minimum event count | ≥ 3 |
| Minimum cumulative distance | ≥ 10 px |
| Maximum average speed | ≤ 2.0 px/ms (distance / elapsed ms) |
| Minimum pause count | ≥ 1 (movement < 0.2 px over > 50 ms) |
| Check | Threshold |
| --------------------------- | ------------------------------------ |
| Minimum event count | ≥ 3 |
| Minimum cumulative distance | ≥ 10 px |
| Maximum average speed | ≤ 2.0 px/ms (distance / elapsed ms) |
| Minimum pause count | ≥ 1 (movement < 0.2 px over > 50 ms) |
### Browser Fingerprint
| Signal | Valid range |
|---|---|
| `aspectRatio` (width / height) | 0.5 – 3.0 |
| `devicePixelRatio` | 0 < dpr ≤ 5.0 |
| `hardwareConcurrency` | ≥ 1 |
| Signal | Valid range |
| ------------------------------ | ------------- |
| `aspectRatio` (width / height) | 0.5 – 3.0 |
| `devicePixelRatio` | 0 < dpr ≤ 5.0 |
| `hardwareConcurrency` | ≥ 1 |
---
@@ -313,21 +387,84 @@ Rate-limited responses are indistinguishable from validation failures.
## SQLite Schema
The schema is extended in v0.6.0 with four new columns to persist per-session
gene mutation state. Migration is additive — columns are created when missing,
preserving compatibility with existing deployments.
```sql
CREATE TABLE IF NOT EXISTS sessions (
session_id TEXT PRIMARY KEY,
public_key BLOB NOT NULL, -- 32-byte Ed25519 verifying key
salt BLOB NOT NULL, -- 16-byte current salt
last_hash BLOB NOT NULL, -- 32-byte Blake3 chain head
chain_length INTEGER NOT NULL DEFAULT 1,
created_at INTEGER NOT NULL, -- Unix ms
last_seen INTEGER NOT NULL, -- Unix ms
expires_at INTEGER NOT NULL -- Unix ms
session_id TEXT PRIMARY KEY,
public_key BLOB NOT NULL, -- 32-byte Ed25519 verifying key
salt BLOB NOT NULL, -- 16-byte current salt
last_hash BLOB NOT NULL, -- 32-byte Blake3 chain head
chain_length INTEGER NOT NULL DEFAULT 1,
created_at INTEGER NOT NULL, -- Unix ms
last_seen INTEGER NOT NULL, -- Unix ms
expires_at INTEGER NOT NULL, -- Unix ms
-- v0.6.0: gene mutation state
gene BLOB NOT NULL DEFAULT X'', -- Vec<u8> gene buffer
environment BLOB NOT NULL DEFAULT X'', -- Vec<(u16, u32)> env records
pending_mutation BLOB NOT NULL DEFAULT X'', -- server-issued mutation program
pending_mutation_step INTEGER NOT NULL DEFAULT 0 -- current mutation step counter
);
```
In-memory SQLite — all sessions lost on server restart by design.
Clients re-initialise transparently on the next page load.
In-memory SQLite (`sqlite-in-memory`) — all sessions lost on server restart by
design. Clients re-initialise transparently on the next page load. Use
`sqlite-in-disk` for persistent sessions across restarts.
---
## Storage Backend (v0.6.0)
ChronoSeal v0.6.0 introduces selectable database backends via the `db_type`
configuration option. The default remains in-memory to preserve ephemeral
session behavior.
### Backend Options
| `db_type` | Behavior |
| ------------------ | -------------------------------------------------------------------- |
| `sqlite-in-memory` | Default. All sessions ephemeral; lost on restart. Zero disk I/O. |
| `sqlite-in-disk` | Persistent sessions. Requires `db_path`. Survives restarts. |
| `valkey` | Compatibility mode. Currently falls back to in-memory. CLI contract preserved. |
### Configuration
**Config file** (`/etc/chronoseal/config.toml`):
```toml
db_type = "sqlite-in-disk"
db_path = "/var/lib/chronoseal/chronoseal.sqlite"
```
**Environment variable**:
```bash
CHRONOSEAL_DB_TYPE=sqlite-in-disk
CHRONOSEAL_DB_PATH=/var/lib/chronoseal/chronoseal.sqlite
```
**CLI flag**:
```bash
chronoseal run --db-type sqlite-in-disk --db-path /var/lib/chronoseal/chronoseal.sqlite
```
**Inspect active backend**:
```bash
chronoseal db-type --format text
```
### Precedence
```
CLI flags > CHRONOSEAL_* environment variables > config file > defaults
```
### Migration Notes
- Schema migration is additive; new columns are created when missing on startup.
- Switching from `sqlite-in-memory` to `sqlite-in-disk` requires no code changes — only config.
- `valkey` is available in the CLI contract today; full backend support is tracked for a future release.
- Existing deployments without the v0.6.0 mutation columns will have those columns added automatically on first start.
---
@@ -335,24 +472,27 @@ Clients re-initialise transparently on the next page load.
### In Scope
| Threat | Mitigation |
|---|---|
| Playwright / Puppeteer / Selenium | Mouse entropy + behavioral validation |
| Puppeteer Stealth, undetected-chromedriver | Signature over VM execution state |
| Heartbeat replay | Hash chain + ±30s timestamp window |
| Signature forgery | Private key isolated in WASM memory |
| Parallel session sharing | Each session bound to a unique keypair |
| Brute-forced session IDs | 256-bit random entropy |
| Flooding with fake session IDs | Rate limiter + periodic HashMap eviction |
| Traffic analysis | Uniform `{"status":"ok"}` on all failure paths |
| Threat | Mitigation |
| ------------------------------------------ | --------------------------------------------------------------- |
| Playwright / Puppeteer / Selenium | Mouse entropy + behavioral validation |
| Puppeteer Stealth, undetected-chromedriver | Signature over VM execution state |
| Heartbeat replay | Hash chain + ±30s timestamp window |
| Mutation replay | mutation_step + gene_commitment parity check (v0.6.0) |
| Mutation tampering | Server recomputes candidate gene from authoritative program (v0.6.0) |
| Signature forgery | Private key isolated in WASM memory |
| Parallel session sharing | Each session bound to a unique keypair |
| Brute-forced session IDs | 256-bit random entropy |
| Flooding with fake session IDs | Rate limiter + periodic HashMap eviction |
| Traffic analysis | Uniform `{"status":"ok"}` on all failure paths |
| Malformed mutation programs | Strict parsing, length caps, underflow/unknown-opcode errors |
### Out of Scope
| Threat | Reason |
|---|---|
| Threat | Reason |
| ---------------------------------- | ---------------------------------------- |
| Real browser with real human input | Indistinguishable from a legitimate user |
| WASM reverse engineering | Obfuscation is not a security primitive |
| Server-side compromise | Outside the scope of client attestation |
| WASM reverse engineering | Obfuscation is not a security primitive |
| Server-side compromise | Outside the scope of client attestation |
ChronoSeal raises cost and complexity of automated access. It is not a
cryptographic proof of humanity and does not claim to be.
@@ -361,23 +501,26 @@ cryptographic proof of humanity and does not claim to be.
## Module Reference
| Path | Purpose |
|---|---|
| `shared/src/protocol.rs` | Shared types: `InitRequest`, `HeartbeatRequest`, `StackState`, … |
| `shared/src/hashing.rs` | `initial_hash`, `next_chain_hash`, `hash_stack` |
| `shared/src/constants.rs` | All tunable parameters |
| `server/src/routes/init.rs` | `POST /init` handler |
| `server/src/routes/heartbeat.rs` | `POST /hb` handler |
| `server/src/session.rs` | `create_session`, `verify_heartbeat` |
| `server/src/crypto.rs` | `verify_signature` — BTreeMap canonical JSON |
| `server/src/trust.rs` | `validate_mouse` — speed, distance, pauses |
| `server/src/fingerprint.rs` | `validate` — aspect ratio, DPR, HW concurrency |
| `server/src/vm.rs` | `generate_random_program` |
| `server/src/ratelimit.rs` | `RateLimiter::check`, `evict_stale` |
| `server/src/cleanup.rs` | Background loop: expire sessions + evict rate limiter |
| `server/src/storage.rs` | SQLite init, `current_time_ms` |
| `wasm/src/crypto.rs` | `generate_keypair`, `sign_message`, `compute_next_hash` |
| `wasm/src/vm.rs` | `run_program` — stack machine executor |
| `frontend/heartbeat.js` | Session init, heartbeat loop, chain advancement |
| `frontend/entropy.js` | Mouse event ring buffer, `collectEntropy` |
| `frontend/transport.js` | `sendRequest` fetch wrapper |
| Path | Purpose |
| ------------------------------------- | -------------------------------------------------------------------- |
| `shared/src/protocol.rs` | Shared types: `InitRequest`, `HeartbeatRequest`, `StackState`, … |
| `shared/src/hashing.rs` | `initial_hash`, `next_chain_hash`, `hash_stack` |
| `shared/src/constants.rs` | All tunable parameters |
| `shared/src/gene.rs` | Gene model, deterministic commitment (`chronoseal/gene/v1`) [v0.6.0] |
| `shared/src/vm_extensions.rs` | Mutation opcode set, shared engine for server/WASM parity [v0.6.0] |
| `server/src/routes/init.rs` | `POST /init` handler |
| `server/src/routes/heartbeat.rs` | `POST /hb` handler |
| `server/src/session.rs` | `create_session`, `verify_heartbeat`, `validate_mutation_parity` |
| `server/src/crypto.rs` | `verify_signature` — BTreeMap canonical JSON |
| `server/src/trust.rs` | `validate_mouse` — speed, distance, pauses |
| `server/src/fingerprint.rs` | `validate` — aspect ratio, DPR, HW concurrency |
| `server/src/vm.rs` | `generate_random_program` |
| `server/src/ratelimit.rs` | `RateLimiter::check`, `evict_stale` |
| `server/src/cleanup.rs` | Background loop: expire sessions + evict rate limiter |
| `server/src/storage.rs` | SQLite init, backend selection, `current_time_ms` |
| `wasm/src/crypto.rs` | `generate_keypair`, `sign_message`, `compute_next_hash` |
| `wasm/src/vm.rs` | `run_program` — stack machine executor |
| `wasm/src/vm_extensions.rs` | `preview_mutation`, `commit_mutation` [v0.6.0] |
| `frontend/heartbeat.js` | Session init, heartbeat loop, chain advancement |
| `frontend/entropy.js` | Mouse event ring buffer, `collectEntropy` |
| `frontend/transport.js` | `sendRequest` fetch wrapper |