feat: match Go TLS fingerprint for MITM upstream (#11)

* feat: match Go TLS fingerprint for MITM upstream connections

Replace rustls with boring2 (BoringSSL) for all MITM→Google upstream
connections, configured with Go crypto/tls exact defaults:

- Cipher suites: TLS_AES_128_GCM_SHA256 + 14 others in Go order
- Curves: X25519, P-256, P-384
- Signature algorithms: ECDSA+SHA256, RSA-PSS+SHA256, etc.
- HTTP/2 SETTINGS: 4MB stream window, 1GB connection window, 10MB
  header list, no adaptive windowing

Local TLS (LS→MITM) still uses rustls for CA cert presentation.
boring2/tokio-boring2 were already compiled as transitive deps from
wreq — no new build time added.

* chore: fmt + update README TLS description

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,102 @@
+name: Bug Report
+description: Something isn't working right
+labels: ["bug"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for reporting! Please fill out the info below so we can debug faster.
+
+  - type: input
+    id: os
+    attributes:
+      label: Operating System
+      description: e.g. Ubuntu 24.04, macOS 15.2, Windows 11
+      placeholder: Ubuntu 24.04
+    validations:
+      required: true
+
+  - type: dropdown
+    id: mode
+    attributes:
+      label: Running Mode
+      description: How are you running ZeroGravity?
+      options:
+        - Headless (default, --headless)
+        - Classic (--classic, attached to running Antigravity)
+        - No MITM (--no-mitm)
+    validations:
+      required: true
+
+  - type: input
+    id: version
+    attributes:
+      label: ZeroGravity Version / Commit
+      description: "Output of `git rev-parse --short HEAD` or the version you downloaded"
+      placeholder: 4966d8f
+    validations:
+      required: true
+
+  - type: input
+    id: model
+    attributes:
+      label: Model Used
+      description: Which model were you using when the issue occurred?
+      placeholder: gemini-3-flash
+
+  - type: textarea
+    id: description
+    attributes:
+      label: What happened?
+      description: Describe the issue clearly. What did you expect vs what actually happened?
+    validations:
+      required: true
+
+  - type: textarea
+    id: logs
+    attributes:
+      label: Logs
+      description: |
+        Paste relevant log output. You can get logs with:
+        - `zg logs-all` (full logs)
+        - `journalctl --user -u zerogravity --no-pager -n 200` (systemd)
+        - Or check `~/.config/zerogravity/` for log files
+      render: text
+
+  - type: textarea
+    id: trace
+    attributes:
+      label: Call Trace
+      description: |
+        If available, paste the trace summary for the failing request.
+        Traces are saved to `~/.config/zerogravity/traces/YYYY-MM-DD/`.
+        You can get the latest one with:
+        ```
+        TRACE_DIR=~/.config/zerogravity/traces/$(date +%Y-%m-%d)
+        cat "$TRACE_DIR/$(ls -t "$TRACE_DIR" | head -1)/summary.md"
+        ```
+      render: markdown
+
+  - type: textarea
+    id: health
+    attributes:
+      label: Health Check Output
+      description: |
+        Paste the output of:
+        ```
+        curl -s http://localhost:8741/health | jq .
+        zg status
+        ```
+      render: json
+
+  - type: textarea
+    id: repro
+    attributes:
+      label: Steps to Reproduce
+      description: How can we reproduce this? Include the curl command or client config if applicable.
+
+  - type: textarea
+    id: extra
+    attributes:
+      label: Additional Context
+      description: Anything else — screenshots, network setup (VPN/proxy), Antigravity version, etc.

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -0,0 +1,23 @@
+name: Feature Request
+description: Suggest an idea or improvement
+labels: ["enhancement"]
+body:
+  - type: textarea
+    id: description
+    attributes:
+      label: What do you want?
+      description: Describe the feature or improvement you'd like to see.
+    validations:
+      required: true
+
+  - type: textarea
+    id: usecase
+    attributes:
+      label: Use Case
+      description: Why do you need this? What problem does it solve?
+
+  - type: textarea
+    id: alternatives
+    attributes:
+      label: Alternatives Considered
+      description: Any workarounds or alternative approaches you've tried?

Cargo.lock

@@ -2366,6 +2366,7 @@ dependencies = [
  "async-stream",
  "axum",
  "base64",
+ "boring2",
  "brotli 7.0.0",
  "bytes",
  "chrono",
@@ -2386,6 +2387,7 @@ dependencies = [
  "serde_json",
  "time",
  "tokio",
+ "tokio-boring2",
  "tokio-rustls",
  "tokio-stream",
  "tower-http",

Cargo.toml

@@ -40,6 +40,8 @@ rustls = { version = "0.23", features = ["ring"] }
 tokio-rustls = "0.26"
 rustls-native-certs = "0.8"
 rustls-pemfile = "2"
+boring2 = "5.0.0-alpha.12"
+tokio-boring2 = "5.0.0-alpha.12"
 time = "0.3"
 base64 = "0.22"
 httparse = "1"

README.md

@@ -20,8 +20,12 @@
 
 > **Early stage.** Ran this on OpenCode with an Ultra account for 3 days straight, stress testing the whole time. No issues so far. For comparison, a Pro account got banned after about 3 hours using CLIProxyAPI / Antigravity Manager. Not using a firewall since I'm living overseas, so your situation may vary if google detects any suspicious activity. PS: The tool call part is still unstable and may hang sometimes.
 >
+> This software is developed on Linux. I aim to support every OS as best as possible, so if there is any issue please open an issue and I will be happy to assist.
+>
 > Star the repo so more people can find it while it still works. Issues and PRs are welcome.
 
+> **Should this stay open source?** [I need your help. Read the discussion and share your thoughts.](https://github.com/NikkeTryHard/zerogravity/discussions/10)
+
 ---
 
 ## Skip Reading This — It's the Age of AI
@@ -57,7 +61,7 @@ Explain to the user what this project unlocks — not what it _is_, but what bec
 
 ## How It Works
 
-The LS or Language Server is Antigravity's closed source Go binary that talks to Google's API over gRPC. The Extension Server is what feeds it auth tokens and settings/configs, we fake it with a stub so the LS thinks it's inside a real Antigravity window. ZeroGravity turns your OpenAI-compatible requests into dummy prompts and tells the LS to make an API call. The MITM proxy intercepts that call before it leaves the machine, swaps in your real prompt, tools, images, and generation params, re-encrypts it with BoringSSL matching Chrome's exact TLS fingerprint, and forwards it to Google. Google sees what looks like a normal Antigravity session. The response streams back as SSE events which the MITM parses for text, thinking tokens, tool calls, and usage. The iptables redirect is a UID-scoped firewall rule that routes only the LS's traffic through the MITM without touching anything else.
+The LS or Language Server is Antigravity's closed source Go binary that talks to Google's API over gRPC. The Extension Server is what feeds it auth tokens and settings/configs, we fake it with a stub so the LS thinks it's inside a real Antigravity window. ZeroGravity turns your OpenAI-compatible requests into dummy prompts and tells the LS to make an API call. The MITM proxy intercepts that call before it leaves the machine, swaps in your real prompt, tools, images, and generation params, re-encrypts it over TLS, and forwards it to Google. All proxy-to-LS communication uses BoringSSL with Chrome's exact TLS and HTTP/2 fingerprint so the LS can't tell it's not a real Antigravity window. Google sees what looks like a normal Antigravity session. The response streams back as SSE events which the MITM parses for text, thinking tokens, tool calls, and usage. The iptables redirect is a UID-scoped firewall rule that routes only the LS's traffic through the MITM without touching anything else.
 
 ```mermaid
 %%{init: {'theme': 'dark', 'themeVariables': {'primaryColor': '#2a2a2a', 'primaryTextColor': '#d0d0d0', 'primaryBorderColor': '#888', 'lineColor': '#888', 'secondaryColor': '#333', 'tertiaryColor': '#3a3a3a', 'edgeLabelBackground': '#2a2a2a', 'nodeTextColor': '#d0d0d0'}}}%%

docs/ls-binary-analysis.md

@@ -505,6 +505,76 @@ Team/organization management. Handles licensing, seats, credits.
 - `UpdateCascadeWebSearchEnabled` — toggle web search
 - `SetUserApiProviderKey` — BYOK key management
 
+### AnalyticsService (7+ methods)
+
+Separate analytics service for recording telemetry and training data.
+
+```
+BatchRecordCompletions
+BatchRecordPrompts
+RecordCommandUsage
+RecordCompletions
+RecordContextToPrompt
+RecordCortexTrajectory
+RecordCortexTrajectoryStep
+```
+
+**Notable:** Distinct from `ApiServerService.Record*` — likely a dedicated analytics pipeline.
+
+### UserAnalyticsService (5+ methods)
+
+Per-user analytics dashboard service.
+
+```
+Analytics
+CascadeAnalytics
+GetAnalytics
+GetPreferredTimeZone
+UserPageAnalytics
+```
+
+### KnowledgeBaseService (17+ methods)
+
+Enterprise knowledge base with multi-source ingestion. Uses OpenSearch backend.
+
+```
+AddGithubUsers
+AddUsers
+CancelKnowledgeBaseJobs
+ConnectKnowledgeBaseAccount
+DeleteKnowledgeBaseConnection
+ForwardSlackPayload
+GetConnectorInternalConfig
+GetKnowledgeBaseConnectorState
+GetKnowledgeBaseItemsFromScopeItems
+GetKnowledgeBaseJobStates
+GetKnowledgeBaseScopeItems
+GetKnowledgeBaseWebhookUrl
+IngestGithubData
+IngestGoogleDriveData
+IngestJiraData
+IngestJiraPayload
+IngestSlackData
+IngestSlackPayload
+KnowledgeBaseSearch
+UpdateConnectorConfig
+```
+
+**Key insight:** Supports ingesting from **GitHub**, **Google Drive**, **Jira**, and **Slack** — full enterprise knowledge integration.
+
+### CodeIndexService (4+ methods)
+
+Code search and indexing. Uses OpenSearch for hybrid vector+keyword search.
+
+```
+GraphSearch
+HybridSearch
+OpenSearchAddRepository
+OpenSearchGetIndex
+```
+
+**Notable:** `GraphSearch` suggests code graph traversal, `HybridSearch` combines vector embeddings with keyword matching.
+
 ### ModelManagementService (8 methods)
 
 Self-hosted model management for hybrid deployments.
@@ -935,6 +1005,539 @@ https://iamcredentials.googleapis.com/v1/ ← Service account impersonation
 
 ---
 
+## Memory & Brain System
+
+The LS has a sophisticated memory system that persists across conversations.
+
+### Memory Sources
+
+```
+MEMORY_SOURCE_UNSPECIFIED
+MEMORY_SOURCE_USER           — manually created by user
+MEMORY_SOURCE_CASCADE         — extracted from cascade conversations
+MEMORY_SOURCE_AUTO_CASCADE    — automatically generated from cascades
+```
+
+### Memory Triggers
+
+```
+MEMORY_TRIGGER_UNSPECIFIED
+MEMORY_TRIGGER_ALWAYS_ON      — always active
+MEMORY_TRIGGER_GLOB           — glob pattern match on file paths
+MEMORY_TRIGGER_MANUAL         — only when explicitly invoked
+MEMORY_TRIGGER_MODEL_DECISION — model decides when to use
+```
+
+### Memory Actions
+
+```
+MEMORY_ACTION_TYPE_UNSPECIFIED
+MEMORY_ACTION_TYPE_CREATE
+MEMORY_ACTION_TYPE_UPDATE
+MEMORY_ACTION_TYPE_DELETE
+```
+
+### Brain Entry Types
+
+```
+BRAIN_ENTRY_TYPE_UNSPECIFIED
+BRAIN_ENTRY_TYPE_PLAN         — implementation plans
+BRAIN_ENTRY_TYPE_TASK         — task checklists
+```
+
+### Brain Update Triggers
+
+```
+BRAIN_UPDATE_TRIGGER_UNSPECIFIED
+BRAIN_UPDATE_TRIGGER_USER_REQUESTED   — user explicitly asks
+BRAIN_UPDATE_TRIGGER_USER_NEW_INFO    — user provides new info
+BRAIN_UPDATE_TRIGGER_RESEARCH_NEW_INFO — research discovers new info
+BRAIN_UPDATE_TRIGGER_SYSTEM_FORCED    — system-initiated update
+```
+
+### Brain Filter Strategies
+
+```
+BRAIN_FILTER_STRATEGY_UNSPECIFIED
+BRAIN_FILTER_STRATEGY_NO_MEMORIES              — exclude all memories
+BRAIN_FILTER_STRATEGY_NO_SYSTEM_INJECTED_STEPS — exclude system steps
+```
+
+---
+
+## Expanded Cascade Configuration Keys
+
+Full list of all cascade config keys extracted from binary (60+ keys):
+
+### Core Behavior
+
+```
+CASCADE_ENFORCE_QUOTA              — quota enforcement toggle
+CASCADE_BASE_MODEL_ID              — default model selection
+CASCADE_DEFAULT_MODEL_OVERRIDE     — model override
+CASCADE_GLOBAL_CONFIG_OVERRIDE     — global cascade config
+CASCADE_MEMORY_CONFIG_OVERRIDE     — memory subsystem config
+CASCADE_PLAN_BASED_CONFIG_OVERRIDE — planner config
+CASCADE_FREE_CONFIG_OVERRIDE       — free-tier config
+```
+
+### Tool Access
+
+```
+CASCADE_ENABLE_MCP_TOOLS           — MCP tool use
+CASCADE_ANTIGRAVITY_BROWSER_TOOLS_ENABLED
+CASCADE_ENABLE_PROXY_WEB_SERVER    — proxy web server
+CASCADE_ENABLE_IDE_TERMINAL_EXECUTION
+CASCADE_VIEW_FILE_TOOL_CONFIG_OVERRIDE
+CASCADE_USE_REPLACE_CONTENT_EDIT_TOOL
+```
+
+### Web Search
+
+```
+CASCADE_WEB_SEARCH_TOOL_ENABLED
+CASCADE_WEB_SEARCH_TOOL_DISABLED
+CASCADE_WEB_SEARCH_TOOL_UNSPECIFIED
+CASCADE_WEB_APP_DEPLOYMENTS_ENABLED
+```
+
+### Extension Code Execution
+
+```
+CASCADE_RUN_EXTENSION_CODE_ENABLED
+CASCADE_RUN_EXTENSION_CODE_DISABLED
+CASCADE_RUN_EXTENSION_CODE_ONLY
+CASCADE_RUN_EXTENSION_CODE_AUTO_RUN_ENABLED
+CASCADE_RUN_EXTENSION_CODE_AUTO_RUN_MODEL_DECIDES
+CASCADE_RUN_EXTENSION_CODE_AUTO_RUN_UNSPECIFIED
+```
+
+### Command Auto-Execution Policy
+
+```
+CASCADE_COMMANDS_AUTO_EXECUTION_UNSPECIFIED
+CASCADE_COMMANDS_AUTO_EXECUTION_OFF    — always ask
+CASCADE_COMMANDS_AUTO_EXECUTION_AUTO   — auto-run safe commands
+CASCADE_COMMANDS_AUTO_EXECUTION_EAGER  — auto-run most commands
+```
+
+### Memory & Learning
+
+```
+CASCADE_ENABLE_AUTOMATED_MEMORIES  — auto-generate memories
+CASCADE_USER_MEMORIES_IN_SYS_PROMPT
+CASCADE_ENABLE_CUSTOM_RECIPES
+CASCADE_BACKGROUND_RESEARCH_CONFIG_OVERRIDE
+CASCADE_USE_EXPERIMENT_CHECKPOINTER
+CASCADE_USE_SUBAGENT_CHECKPOINTER
+```
+
+### Autocomplete & Input
+
+```
+CASCADE_INPUT_AUTOCOMPLETE_ENABLED
+CASCADE_INPUT_AUTOCOMPLETE_DISABLED
+CASCADE_INPUT_AUTOCOMPLETE_UNSPECIFIED
+CASCADE_RECIPES_AT_MENTION_VISIBILITY
+```
+
+### Run Status
+
+```
+CASCADE_RUN_STATUS_UNSPECIFIED
+CASCADE_RUN_STATUS_IDLE
+CASCADE_RUN_STATUS_BUSY
+CASCADE_RUN_STATUS_RUNNING
+CASCADE_RUN_STATUS_CANCELING
+```
+
+### Edit Importance (for code diffs)
+
+```
+CASCADE_EDIT_IMPORTANCE_UNSPECIFIED
+CASCADE_EDIT_IMPORTANCE_LOW
+CASCADE_EDIT_IMPORTANCE_MEDIUM
+CASCADE_EDIT_IMPORTANCE_HIGH
+```
+
+### Seat Types
+
+```
+CASCADE_SEAT_TYPE_UNSPECIFIED
+CASCADE_SEAT_TYPE_ENTRY      — entry tier
+CASCADE_SEAT_TYPE_STANDARD   — standard tier
+```
+
+---
+
+## Supercomplete (Tab Completion) System
+
+The "Supercomplete" system powers multi-line tab completions, distinct from basic autocomplete.
+
+### Trigger Conditions
+
+```
+SUPERCOMPLETE_TRIGGER_CONDITION_UNSPECIFIED
+SUPERCOMPLETE_TRIGGER_CONDITION_TYPING
+SUPERCOMPLETE_TRIGGER_CONDITION_AUTOCOMPLETE_ACCEPT
+SUPERCOMPLETE_TRIGGER_CONDITION_AUTOCOMPLETE_PREDICTIVE
+SUPERCOMPLETE_TRIGGER_CONDITION_SUPERCOMPLETE_ACCEPT
+SUPERCOMPLETE_TRIGGER_CONDITION_SUPERCOMPLETE_PREDICTIVE
+SUPERCOMPLETE_TRIGGER_CONDITION_TAB_JUMP_ACCEPT
+SUPERCOMPLETE_TRIGGER_CONDITION_TAB_JUMP_EDIT
+SUPERCOMPLETE_TRIGGER_CONDITION_TAB_JUMP_PREDICTIVE
+SUPERCOMPLETE_TRIGGER_CONDITION_CURSOR_LINE_NAVIGATION
+SUPERCOMPLETE_TRIGGER_CONDITION_FORCED
+```
+
+### Filters
+
+```
+SUPERCOMPLETE_FILTER_PREFIX_MATCH
+SUPERCOMPLETE_FILTER_SUFFIX_MATCH
+SUPERCOMPLETE_FILTER_INSERTION_CAP
+SUPERCOMPLETE_FILTER_DELETION_CAP
+SUPERCOMPLETE_FILTER_NO_OP
+SUPERCOMPLETE_FILTER_REVERT
+SUPERCOMPLETE_FILTER_PREVIOUSLY_SHOWN
+SUPERCOMPLETE_FILTER_WHITESPACE_ONLY
+SUPERCOMPLETE_FILTER_SCORE_THRESHOLD
+```
+
+### Config Keys
+
+```
+SUPERCOMPLETE_TEMPERATURE
+SUPERCOMPLETE_MODEL_CONFIG
+SUPERCOMPLETE_LINE_RADIUS
+SUPERCOMPLETE_MIN_SCORE
+SUPERCOMPLETE_MAX_INSERTIONS
+SUPERCOMPLETE_MAX_DELETIONS
+SUPERCOMPLETE_MAX_TRAJECTORY_STEPS
+SUPERCOMPLETE_MAX_TRAJECTORY_STEP_SIZE
+SUPERCOMPLETE_MAX_CONCURRENT_REQUESTS
+SUPERCOMPLETE_FAST_DEBOUNCE
+SUPERCOMPLETE_REGULAR_DEBOUNCE
+SUPERCOMPLETE_RECENT_STEPS_DURATION
+SUPERCOMPLETE_USE_CODE_DIAGNOSTICS
+SUPERCOMPLETE_CODE_DIAGNOSTICS_TOP_K
+SUPERCOMPLETE_DIAGNOSTIC_SEVERITY_THRESHOLD
+SUPERCOMPLETE_DISABLE_TYPING_CACHE
+SUPERCOMPLETE_DONT_FILTER_MID_STREAMED
+SUPERCOMPLETE_ALWAYS_USE_CACHE_ON_EQUAL_STATE
+SUPERCOMPLETE_CACHE_ON_PARENT_ID_KILL_SWITCH
+SUPERCOMPLETE_ON_ACCEPT_ONLY
+SUPERCOMPLETE_PRUNE_RESPONSE
+SUPERCOMPLETE_PRUNE_MAX_INSERT_DELETE_LINE_DELTA
+SUPERCOMPLETE_INLINE_PURE_DELETE
+SUPERCOMPLETE_INLINE_RICH_GHOST_TEXT_INSERTIONS
+SUPERCOMPLETE_USE_CURRENT_LINE
+SUPERCOMPLETE_NO_ACTIVE_NODE
+```
+
+### Tab Jump (Cursor Navigation)
+
+```
+TAB_JUMP_ENABLED
+TAB_JUMP_LINE_RADIUS
+TAB_JUMP_CUMULATIVE_PROMPT_CONFIG
+TAB_JUMP_FILTER_IN_SELECTION
+TAB_JUMP_FILTER_INSERTION_CAP
+TAB_JUMP_FILTER_DELETION_CAP
+TAB_JUMP_FILTER_SCORE_THRESHOLD
+TAB_JUMP_FILTER_WHITESPACE_ONLY
+TAB_JUMP_FILTER_NO_OP
+TAB_JUMP_FILTER_REVERT
+TAB_JUMP_STOP_TOKEN_MIDSTREAM
+TAB_JUMP_ON_ACCEPT_ONLY
+TAB_JUMP_PRUNE_RESPONSE
+TAB_JUMP_PRUNE_MAX_INSERT_DELETE_LINE_DELTA
+TAB_JUMP_MIN_FILTER_RADIUS
+```
+
+---
+
+## Browser Automation Policies
+
+### JS Execution Policy (user can control)
+
+```
+BROWSER_JS_EXECUTION_POLICY_UNSPECIFIED
+BROWSER_JS_EXECUTION_POLICY_ALWAYS_ASK
+BROWSER_JS_EXECUTION_POLICY_MODEL_DECIDES
+BROWSER_JS_EXECUTION_POLICY_TURBO      — never ask
+BROWSER_JS_EXECUTION_POLICY_DISABLED
+```
+
+### JS Auto-Run Policy (cascade-level)
+
+```
+BROWSER_JS_AUTO_RUN_POLICY_UNSPECIFIED
+BROWSER_JS_AUTO_RUN_POLICY_ENABLED
+BROWSER_JS_AUTO_RUN_POLICY_DISABLED
+BROWSER_JS_AUTO_RUN_POLICY_MODEL_DECIDES
+```
+
+### Browser Subagent Mode
+
+```
+BROWSER_SUBAGENT_MODE_UNSPECIFIED
+BROWSER_SUBAGENT_MODE_MAIN_AGENT_ONLY
+BROWSER_SUBAGENT_MODE_SUBAGENT_ONLY
+BROWSER_SUBAGENT_MODE_SUBAGENT_PRIMARILY
+BROWSER_SUBAGENT_MODE_BOTH_AGENTS
+```
+
+### Tool Set Mode (input/output level)
+
+```
+BROWSER_TOOL_SET_MODE_UNSPECIFIED
+BROWSER_TOOL_SET_MODE_ALL_TOOLS
+BROWSER_TOOL_SET_MODE_PIXEL_ONLY
+BROWSER_TOOL_SET_MODE_ALL_INPUT_PIXEL_OUTPUT
+```
+
+### Ephemeral Options (what gets captured)
+
+```
+BROWSER_EPHEMERAL_OPTION_UNSPECIFIED
+BROWSER_EPHEMERAL_OPTION_DOM
+BROWSER_EPHEMERAL_OPTION_SCREENSHOT
+```
+
+### Action Waiting Reasons
+
+```
+BROWSER_ACTION_WAITING_REASON_UNSPECIFIED
+BROWSER_ACTION_WAITING_REASON_PAGE_ACCESS
+BROWSER_ACTION_WAITING_REASON_ACTION_PERMISSION
+BROWSER_ACTION_WAITING_REASON_PAGE_ACCESS_AND_ACTION_PERMISSION
+```
+
+### Installation Status
+
+```
+BROWSER_INSTALLATION_STATUS_UNSPECIFIED
+BROWSER_INSTALLATION_STATUS_NOT_INSTALLED
+BROWSER_INSTALLATION_STATUS_IN_PROGRESS
+BROWSER_INSTALLATION_STATUS_COMPLETE
+BROWSER_INSTALLATION_STATUS_ERROR
+```
+
+---
+
+## Sandbox System (macOS Seatbelt)
+
+The LS includes a `sandbox-wrapper.sh` that sandboxes command execution on macOS using Apple's Seatbelt framework.
+
+### Key Behaviors
+
+- **File writes**: Denied by default, allowed only to workspace dir and `/tmp`
+- **Network**: Denied unless `--allow-network` flag is passed
+- **Gitignore**: Reads `.gitignore` and `.agyignore` to deny access to ignored files
+- **Process isolation**: Uses `sandbox-exec` with a generated Seatbelt profile
+- **Violation detection**: Detects "Operation not permitted" errors and suggests disabling sandbox
+
+### `.agyignore` File
+
+Custom ignore file (like `.gitignore`) specifically for the sandbox. Patterns in `.agyignore` deny both read and write access within the sandbox.
+
+---
+
+## Trainer / RLHF Infrastructure
+
+The binary contains extensive proto definitions for model training, suggesting the LS participates in or configures training runs.
+
+### Proto Package: `exa.trainer_pb`
+
+**Training Objectives:**
+
+```
+DPOConfig           — Direct Preference Optimization
+KTOConfig           — Kahneman-Tversky Optimization
+OnPolicyGRPOConfig  — Group Relative Policy Optimization
+KnowledgeDistillationConfig
+PreferenceLoss      — preference-based loss functions
+```
+
+**Model Architecture:**
+
+```
+BaseModelConfig
+EncoderDecoderModelConfig
+MixtureOfExpertsConfig       — MoE architecture
+MultiLatentAttentionConfig   — MLA (DeepSeek-style?)
+MultiTokenPredictionConfig
+CrossAttentionConfig
+SlidingWindowAttentionConfig
+```
+
+**Quantization:**
+
+```
+QuantizationConfig
+QuantizationMethod
+QuantizationPrecision
+QuantizationPolicy / PolicySet
+LinearQuantization
+LayerNormQuantization
+```
+
+**Training Infrastructure:**
+
+```
+OptimizerType / OptimizerExpAvgDtype
+CheckpointBackend (TORCH_DCP, ZARR)
+ParallelismConfig / LayerParallelismConfig
+RoPEEmbeddingConfig (Llama, DeepseekV scaling)
+SGLangInferenceProviderConfig
+MockedInferenceProviderConfig
+```
+
+**Experiment Management:**
+
+```
+ExperimentProject / ExperimentMetadata
+SweepAxis / SweepItem
+ScheduledModel / SchedulingGroupConfig
+DeviceWorkerRoutingInfo
+DraftTargetModelPair    — speculative decoding?
+```
+
+### Key Proto Packages
+
+```
+exa.cortex_pb        — agent/cascade core
+exa.chat_pb          — chat message/conversation protos
+exa.trainer_pb       — training/RLHF
+exa.analytics_pb     — telemetry
+exa.api_server_pb    — cloud API server
+exa.seat_management_pb — user/team management
+exa.user_analytics_pb  — user analytics
+exa.opensearch_clients_pb — knowledge base / code index
+exa.language_server_pb    — LS service
+exa.extension_server_pb   — extension server
+exa.model_management_pb   — model management
+```
+
+---
+
+## MCP Integration Constants
+
+```
+MCP_SERVER_STATUS_UNSPECIFIED
+MCP_SERVER_STATUS_PENDING
+MCP_SERVER_STATUS_READY
+MCP_SERVER_STATUS_ERROR
+MCP_ADD_SERVER
+MCP_SAVE_CONFIG
+MCP_EXPAND_TOOLS
+MCP_TOOL
+MCP_RESOURCE
+```
+
+---
+
+## Cortex Step Statuses
+
+```
+CORTEX_STEP_STATUS_UNSPECIFIED
+CORTEX_STEP_STATUS_PENDING
+CORTEX_STEP_STATUS_QUEUED
+CORTEX_STEP_STATUS_GENERATING
+CORTEX_STEP_STATUS_RUNNING
+CORTEX_STEP_STATUS_WAITING
+CORTEX_STEP_STATUS_DONE
+CORTEX_STEP_STATUS_ERROR
+CORTEX_STEP_STATUS_CANCELED
+CORTEX_STEP_STATUS_CLEARED
+CORTEX_STEP_STATUS_HALTED
+CORTEX_STEP_STATUS_INTERRUPTED
+CORTEX_STEP_STATUS_INVALID
+```
+
+### Step Sources
+
+```
+CORTEX_STEP_SOURCE_UNSPECIFIED
+CORTEX_STEP_SOURCE_MODEL          — generated by LLM
+CORTEX_STEP_SOURCE_SYSTEM         — system-generated
+CORTEX_STEP_SOURCE_SYSTEM_SDK     — SDK-generated
+CORTEX_STEP_SOURCE_USER_EXPLICIT  — user-initiated
+CORTEX_STEP_SOURCE_USER_IMPLICIT  — implied by user action
+```
+
+### Step Credit Reasons
+
+```
+CORTEX_STEP_CREDIT_REASON_UNSPECIFIED
+CORTEX_STEP_CREDIT_REASON_LINT_FIXING_DISCOUNT — lint fixes are discounted
+```
+
+### Manager Feedback Status
+
+```
+CORTEX_STEP_MANAGER_FEEDBACK_STATUS_UNSPECIFIED
+CORTEX_STEP_MANAGER_FEEDBACK_STATUS_APPROVED
+CORTEX_STEP_MANAGER_FEEDBACK_STATUS_DENIED
+CORTEX_STEP_MANAGER_FEEDBACK_STATUS_ERROR
+```
+
+### Error Categories
+
+```
+CORTEX_ERROR_CATEGORY_UNSPECIFIED
+CORTEX_ERROR_CATEGORY_OVERALL
+CORTEX_ERROR_CATEGORY_ACTION_PREPARE
+CORTEX_ERROR_CATEGORY_ACTION_APPLY
+```
+
+### Compile Tools (Lint Integration)
+
+```
+CORTEX_STEP_COMPILE_TOOL_UNSPECIFIED
+CORTEX_STEP_COMPILE_TOOL_PYLINT
+```
+
+---
+
+## Onboarding Flow
+
+```
+ONBOARDING_PROGRESS_UNKNOWN
+ONBOARDING_PROGRESS_NONE
+ONBOARDING_PROGRESS_ELIGIBLE
+ONBOARDING_PROGRESS_ONBOARDED
+
+ONBOARDING_ACTION_TYPE_UNSPECIFIED
+ONBOARDING_ACTION_TYPE_CHAT
+ONBOARDING_ACTION_TYPE_AUTOCOMPLETE
+ONBOARDING_ACTION_TYPE_COMMAND
+
+ONBOARDING_PAGE_TYPE_UNSPECIFIED
+ONBOARDING_PAGE_TYPE_HOTKEY
+ONBOARDING_PAGE_TYPE_LENS
+ONBOARDING_PAGE_TYPE_SEARCH
+```
+
+**Onboarding pages discovered:**
+
+```
+ONBOARDING_LANDING_PAGE_OPENED
+ONBOARDING_AUTH_PAGE_OPENED
+ONBOARDING_AUTH_MANUAL_PAGE_OPENED
+ONBOARDING_CHOOSE_THEME_PAGE_OPENED
+ONBOARDING_KEYBINDINGS_PAGE_OPENED
+ONBOARDING_AGENT_CONFIG_PAGE_OPENED
+ONBOARDING_IMPORT_PAGE_OPENED
+ONBOARDING_MIGRATION_SCOPE_PAGE_OPENED
+ONBOARDING_SETUP_PAGE_OPENED
+ONBOARDING_TERMS_OF_USE_PAGE_OPENED
+ONBOARDING_USAGE_MODE_PAGE_OPENED
+```
+
+---
+
 ## Protobuf Enum Numbers (from extension.js)
 
 Extracted from the compiled protobuf enum definitions in `extension.js`.

scripts/setup-linux.sh

@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 # ZeroGravity — Linux setup
-# Creates the zerogravity-ls system user for UID-scoped iptables isolation,
-# installs the systemd user service, and builds the dns_redirect.so preload lib.
+# Checks prerequisites, creates the zerogravity-ls system user for
+# UID-scoped iptables isolation, and builds the release binary.
 set -euo pipefail
 
 SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
@@ -18,7 +18,26 @@ if [ ${#MISSING[@]} -gt 0 ]; then
     exit 1
 fi
 
-# ── 1. System user for UID isolation ──
+# ── 1. Prerequisite check: Antigravity must be installed ──
+LS_BINARY="${ZEROGRAVITY_LS_PATH:-/usr/share/antigravity/resources/app/extensions/antigravity/bin/language_server_linux_x64}"
+echo "→ Checking for Antigravity installation…"
+if [ ! -f "$LS_BINARY" ]; then
+    echo ""
+    echo "✗ Antigravity is not installed (or the LS binary is missing)."
+    echo "  ZeroGravity requires a working Antigravity installation."
+    echo "  The Language Server binary is bundled with the Antigravity app"
+    echo "  and cannot be downloaded separately."
+    echo ""
+    echo "  Expected path:"
+    echo "    $LS_BINARY"
+    echo ""
+    echo "  Install Antigravity first, then re-run this script."
+    echo "  Alternatively, set ZEROGRAVITY_LS_PATH to a custom LS binary location."
+    exit 1
+fi
+echo "  Found: $LS_BINARY"
+
+# ── 2. System user for UID isolation ──
 echo "→ Creating zerogravity-ls system user…"
 if id -u zerogravity-ls &>/dev/null; then
     echo "  Already exists."
@@ -27,7 +46,7 @@ else
     echo "  Created."
 fi
 
-# ── 2. Sudoers rule (run commands as zerogravity-ls without password) ──
+# ── 3. Sudoers rule (run commands as zerogravity-ls without password) ──
 SUDOERS="/etc/sudoers.d/zerogravity"
 echo "→ Installing sudoers rule…"
 if [ -f "$SUDOERS" ]; then
@@ -38,41 +57,15 @@ else
     echo "  Installed: $SUDOERS"
 fi
 
-# ── 3. Data directory permissions ──
+# ── 4. Data directory permissions ──
 echo "→ Setting up /tmp/zerogravity-standalone…"
 sudo mkdir -p /tmp/zerogravity-standalone
 sudo chmod 1777 /tmp/zerogravity-standalone
 
-# ── 4. Config directory ──
+# ── 5. Config directory ──
 echo "→ Setting up ~/.config/zerogravity…"
 mkdir -p "$HOME/.config/zerogravity"
 
-# ── 5. Systemd user service ──
-echo "→ Installing systemd user service…"
-UNIT_DIR="$HOME/.config/systemd/user"
-mkdir -p "$UNIT_DIR"
-cat > "$UNIT_DIR/zerogravity.service" << EOF
-[Unit]
-Description=ZeroGravity Proxy
-After=network.target
-
-[Service]
-Type=simple
-ExecStart=$PROJECT_DIR/target/release/zerogravity
-WorkingDirectory=$PROJECT_DIR
-Environment=RUST_LOG=info
-Restart=on-failure
-RestartSec=3
-StandardOutput=journal
-StandardError=journal
-
-[Install]
-WantedBy=default.target
-EOF
-systemctl --user daemon-reload
-echo "  Installed: $UNIT_DIR/zerogravity.service"
-echo "  Enable with: systemctl --user enable zerogravity"
-
 # ── 6. Build ──
 echo "→ Building release binary…"
 cd "$PROJECT_DIR"

scripts/setup-macos.sh

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 # ZeroGravity — macOS setup
-# Installs a launchd plist for automatic startup and sets up config directories.
+# Checks prerequisites, sets up config directories, and builds the release binary.
 # No UID isolation on macOS — runs in headless/HTTPS_PROXY mode only.
 set -euo pipefail
 
@@ -16,50 +16,37 @@ mkdir -p "$CONFIG_DIR"
 echo "→ Setting up /tmp/zerogravity-standalone…"
 mkdir -p /tmp/zerogravity-standalone
 
-# ── 3. Launchd plist ──
-echo "→ Installing launchd plist…"
-PLIST_DIR="$HOME/Library/LaunchAgents"
-PLIST="$PLIST_DIR/com.zerogravity.proxy.plist"
-mkdir -p "$PLIST_DIR"
-cat > "$PLIST" << EOF
-<?xml version="1.0" encoding="UTF-8"?>
-<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
-<plist version="1.0">
-<dict>
-    <key>Label</key>
-    <string>com.zerogravity.proxy</string>
-    <key>ProgramArguments</key>
-    <array>
-        <string>$PROJECT_DIR/target/release/zerogravity</string>
-    </array>
-    <key>WorkingDirectory</key>
-    <string>$PROJECT_DIR</string>
-    <key>EnvironmentVariables</key>
-    <dict>
-        <key>RUST_LOG</key>
-        <string>info</string>
-    </dict>
-    <key>KeepAlive</key>
-    <dict>
-        <key>SuccessfulExit</key>
-        <false/>
-    </dict>
-    <key>StandardOutPath</key>
-    <string>$HOME/Library/Logs/zerogravity.log</string>
-    <key>StandardErrorPath</key>
-    <string>$HOME/Library/Logs/zerogravity.log</string>
-</dict>
-</plist>
-EOF
-echo "  Installed: $PLIST"
-echo "  Start with: launchctl load $PLIST"
-echo "  Stop with:  launchctl unload $PLIST"
+# ── 3. Prerequisite check: Antigravity must be installed ──
+LS_BINARY="${ZEROGRAVITY_LS_PATH:-}"
+if [ -z "$LS_BINARY" ]; then
+    # Check both /Applications and ~/Applications
+    for base in "/Applications/Antigravity.app" "$HOME/Applications/Antigravity.app"; do
+        candidate="$base/Contents/Resources/app/extensions/antigravity/bin/language_server_darwin_arm64"
+        if [ -f "$candidate" ]; then
+            LS_BINARY="$candidate"
+            break
+        fi
+    done
+fi
+echo "→ Checking for Antigravity installation…"
+if [ -z "$LS_BINARY" ] || [ ! -f "$LS_BINARY" ]; then
+    echo ""
+    echo "✗ Antigravity is not installed (or the LS binary is missing)."
+    echo "  ZeroGravity requires a working Antigravity installation."
+    echo "  The Language Server binary is bundled with the Antigravity app"
+    echo "  and cannot be downloaded separately."
+    echo ""
+    echo "  Expected in: /Applications/Antigravity.app or ~/Applications/Antigravity.app"
+    echo ""
+    echo "  Install Antigravity first, then re-run this script."
+    echo "  Alternatively, set ZEROGRAVITY_LS_PATH to a custom LS binary location."
+    exit 1
+fi
+echo "  Found: $LS_BINARY"
 
 # ── 4. Build ──
 echo "→ Building release binary…"
 cd "$PROJECT_DIR"
 cargo build --release 2>&1 | tail -1
 echo ""
-echo "✓ Setup complete."
-echo "  Start with: launchctl load $PLIST"
-echo "  Or manually: zg start"
+echo "✓ Setup complete. Start with: zg start"

scripts/setup-windows.ps1

@@ -1,6 +1,5 @@
 # ZeroGravity — Windows setup
-# Creates config directories, builds the release binary, and optionally
-# installs as a scheduled task for automatic startup.
+# Creates config directories, checks prerequisites, and builds the release binary.
 # Run as: powershell -ExecutionPolicy Bypass -File scripts\setup-windows.ps1
 
 $ErrorActionPreference = "Stop"
@@ -19,7 +18,26 @@ $DataDir = Join-Path $env:TEMP "zerogravity-standalone"
 New-Item -ItemType Directory -Force -Path $DataDir | Out-Null
 Write-Host "  $DataDir"
 
-# ── 3. Build ──
+# ── 3. Prerequisite check: Antigravity must be installed ──
+Write-Host "→ Checking for Antigravity installation…"
+$LsBinary = Join-Path $env:LOCALAPPDATA "Programs\Antigravity\resources\app\extensions\antigravity\bin\language_server_windows_x64.exe"
+if (-not (Test-Path $LsBinary)) {
+    Write-Host ""
+    Write-Host "✗ Antigravity is not installed (or the LS binary is missing)." -ForegroundColor Red
+    Write-Host "  ZeroGravity requires a working Antigravity installation."
+    Write-Host "  The Language Server binary is bundled with the Antigravity app"
+    Write-Host "  and cannot be downloaded separately."
+    Write-Host ""
+    Write-Host "  Expected path:"
+    Write-Host "    $LsBinary"
+    Write-Host ""
+    Write-Host "  Install Antigravity first, then re-run this script."
+    Write-Host "  Alternatively, set ZEROGRAVITY_LS_PATH to a custom LS binary location."
+    exit 1
+}
+Write-Host "  Found: $LsBinary"
+
+# ── 4. Build ──
 Write-Host "→ Building release binary…"
 Push-Location $ProjectDir
 cargo build --release
@@ -32,37 +50,6 @@ if (-not (Test-Path $Binary)) {
 }
 Write-Host "  Built: $Binary"
 
-# ── 4. Scheduled task (optional) ──
-$TaskName = "ZeroGravity Proxy"
-$Existing = Get-ScheduledTask -TaskName $TaskName -ErrorAction SilentlyContinue
-
-if ($Existing) {
-    Write-Host "→ Scheduled task '$TaskName' already exists. Updating…"
-    Unregister-ScheduledTask -TaskName $TaskName -Confirm:$false
-}
-
-Write-Host "→ Creating scheduled task '$TaskName'…"
-$Action = New-ScheduledTaskAction `
-    -Execute $Binary `
-    -WorkingDirectory $ProjectDir
-
-$Trigger = New-ScheduledTaskTrigger -AtLogOn
-$Settings = New-ScheduledTaskSettingsSet `
-    -AllowStartIfOnBatteries `
-    -DontStopIfGoingOnBatteries `
-    -RestartCount 3 `
-    -RestartInterval (New-TimeSpan -Minutes 1)
-
-Register-ScheduledTask `
-    -TaskName $TaskName `
-    -Action $Action `
-    -Trigger $Trigger `
-    -Settings $Settings `
-    -Description "ZeroGravity OpenAI-compatible proxy" | Out-Null
-
-Write-Host "  Installed as logon task."
 Write-Host ""
 Write-Host "✓ Setup complete."
-Write-Host "  Start now:  schtasks /run /tn '$TaskName'"
-Write-Host "  Stop:       schtasks /end /tn '$TaskName'"
-Write-Host "  Or manually: .\target\release\zerogravity.exe"
+Write-Host "  Start: .\target\release\zerogravity.exe"

src/bin/zg.rs

@@ -325,9 +325,7 @@ fn svc_stop() -> bool {
     }
     #[cfg(not(windows))]
     {
-        let _ = Command::new("pkill")
-            .args(["-f", "zerogravity"])
-            .status();
+        let _ = Command::new("pkill").args(["-f", "zerogravity"]).status();
     }
     true
 }
@@ -517,9 +515,8 @@ fn do_test(msg: &str) {
         .replace('\n', "\\n")
         .replace('\r', "\\r")
         .replace('\t', "\\t");
-    let body = format!(
-        r#"{{"model":"gemini-3-flash","input":"{escaped}","stream":false,"timeout":30}}"#
-    );
+    let body =
+        format!(r#"{{"model":"gemini-3-flash","input":"{escaped}","stream":false,"timeout":30}}"#);
     match curl_post("/v1/responses", &body) {
         Some(json) => jq_print(&json),
         None => {

src/mitm/h2_handler.rs

@@ -42,15 +42,15 @@ use tracing::{debug, info, trace, warn};
 /// We mirror this by maintaining a single upstream connection per domain.
 struct UpstreamPool {
     domain: String,
-    tls_config: Arc<rustls::ClientConfig>,
+    tls_connector: boring2::ssl::SslConnector,
     sender: Mutex<Option<hyper::client::conn::http2::SendRequest<Full<Bytes>>>>,
 }
 
 impl UpstreamPool {
-    fn new(domain: String, tls_config: Arc<rustls::ClientConfig>) -> Self {
+    fn new(domain: String, tls_connector: boring2::ssl::SslConnector) -> Self {
         Self {
             domain,
-            tls_config,
+            tls_connector,
             sender: Mutex::new(None),
         }
     }
@@ -82,17 +82,29 @@ impl UpstreamPool {
             .await
             .map_err(|e| format!("upstream TCP connect to {} failed: {e}", self.domain))?;
 
-        let connector = tokio_rustls::TlsConnector::from(self.tls_config.clone());
-        let server_name = rustls::pki_types::ServerName::try_from(self.domain.clone())
-            .map_err(|e| format!("invalid domain {}: {e}", self.domain))?;
+        let ssl = self
+            .tls_connector
+            .configure()
+            .map_err(|e| format!("SSL configure: {e}"))?
+            .into_ssl(&self.domain)
+            .map_err(|e| format!("SSL into_ssl: {e}"))?;
 
-        let upstream_tls = connector
-            .connect(server_name, upstream_tcp)
-            .await
+        let mut upstream_tls = tokio_boring2::SslStream::new(ssl, upstream_tcp)
             .map_err(|e| format!("upstream TLS to {} failed: {e}", self.domain))?;
 
+        std::pin::Pin::new(&mut upstream_tls)
+            .connect()
+            .await
+            .map_err(|e| format!("TLS handshake to {} failed: {e}", self.domain))?;
+
         let upstream_io = TokioIo::new(upstream_tls);
+        // Configure HTTP/2 SETTINGS to match Go's net/http2 defaults
+        // Source: golang.org/x/net/http2/transport.go
         let (sender, conn) = hyper::client::conn::http2::Builder::new(TokioExecutor::new())
+            .initial_stream_window_size(4 << 20) // 4MB  (Go: transportDefaultStreamFlow)
+            .initial_connection_window_size(1 << 30) // 1GB  (Go: transportDefaultConnFlow)
+            .max_header_list_size(10 * 1024 * 1024) // 10MB (Go: defaultMaxHeaderListSize)
+            .adaptive_window(false) // Go doesn't use adaptive windowing
             .handshake(upstream_io)
             .await
             .map_err(|e| format!("upstream h2 handshake to {} failed: {e}", self.domain))?;
@@ -140,22 +152,11 @@ where
 {
     info!(domain = %domain, "MITM H2: handling HTTP/2 connection");
 
-    // Build TLS config for upstream connections
-    let mut root_store = rustls::RootCertStore::empty();
-    let native_certs = rustls_native_certs::load_native_certs();
-    for cert in native_certs.certs {
-        let _ = root_store.add(cert);
-    }
-    let mut upstream_tls_config = rustls::ClientConfig::builder()
-        .with_root_certificates(root_store)
-        .with_no_client_auth();
-    upstream_tls_config.alpn_protocols = vec![b"h2".to_vec()];
+    // Build upstream TLS connector matching Go's crypto/tls fingerprint (with ALPN h2)
+    let upstream_connector = super::tls::build_go_tls_connector(Some(&[b"h2"]));
 
     // Shared upstream connection pool (single connection, multiplexed)
-    let pool = Arc::new(UpstreamPool::new(
-        domain.clone(),
-        Arc::new(upstream_tls_config),
-    ));
+    let pool = Arc::new(UpstreamPool::new(domain.clone(), upstream_connector));
 
     let io = TokioIo::new(tls_stream);
     let domain = Arc::new(domain);

src/mitm/mod.rs

@@ -18,3 +18,4 @@ pub mod modify;
 pub mod proto;
 pub mod proxy;
 pub mod store;
+pub mod tls;

src/mitm/proxy.rs

@@ -368,20 +368,11 @@ async fn handle_http_over_tls(
 ) -> Result<(), String> {
     let mut tmp = vec![0u8; 32768];
 
-    // Build upstream TLS connector once for this connection
-    let mut root_store = rustls::RootCertStore::empty();
-    let native_certs = rustls_native_certs::load_native_certs();
-    for cert in native_certs.certs {
-        let _ = root_store.add(cert);
-    }
-    let upstream_config = Arc::new(
-        rustls::ClientConfig::builder()
-            .with_root_certificates(root_store)
-            .with_no_client_auth(),
-    );
+    // Build upstream TLS connector matching Go's crypto/tls fingerprint
+    let upstream_connector = super::tls::build_go_tls_connector(None);
 
     // Reusable upstream connection — created lazily, reconnected if stale
-    let mut upstream: Option<tokio_rustls::client::TlsStream<TcpStream>> = None;
+    let mut upstream: Option<tokio_boring2::SslStream<TcpStream>> = None;
 
     // Keep-alive loop: handle multiple requests on this connection
     loop {
@@ -575,7 +566,7 @@ async fn handle_http_over_tls(
         let conn = match upstream.as_mut() {
             Some(c) => c,
             None => {
-                let c = connect_upstream(domain, &upstream_config).await?;
+                let c = connect_upstream(domain, &upstream_connector).await?;
                 upstream.insert(c)
             }
         };
@@ -583,7 +574,7 @@ async fn handle_http_over_tls(
         // Forward the request — if write fails, reconnect and retry once
         if let Err(e) = conn.write_all(&request_buf).await {
             debug!(domain, error = %e, "MITM: upstream write failed, reconnecting");
-            let c = connect_upstream(domain, &upstream_config).await?;
+            let c = connect_upstream(domain, &upstream_connector).await?;
             let conn = upstream.insert(c);
             conn.write_all(&request_buf)
                 .await
@@ -905,15 +896,15 @@ async fn read_full_request(
 
 /// Connect (or reconnect) to the real upstream via TLS.
 ///
+/// Uses BoringSSL configured to match Go's `crypto/tls` fingerprint.
 /// Bypasses /etc/hosts by resolving via direct DNS query (dig @8.8.8.8),
 /// then falls back to cached IPs file, then to normal system resolution.
 async fn connect_upstream(
     domain: &str,
-    config: &Arc<rustls::ClientConfig>,
-) -> Result<tokio_rustls::client::TlsStream<TcpStream>, String> {
-    let connector = tokio_rustls::TlsConnector::from(config.clone());
+    connector: &boring2::ssl::SslConnector,
+) -> Result<tokio_boring2::SslStream<TcpStream>, String> {
     let addr = resolve_upstream(domain).await;
-    info!(domain, addr = %addr, "MITM: connecting upstream");
+    info!(domain, addr = %addr, "MITM: connecting upstream (BoringSSL)");
 
     let tcp = match tokio::time::timeout(
         std::time::Duration::from_secs(15),
@@ -926,20 +917,26 @@ async fn connect_upstream(
         Err(_) => return Err(format!("Connect to upstream {domain} ({addr}): timed out")),
     };
 
-    let server_name = rustls::pki_types::ServerName::try_from(domain.to_string())
-        .map_err(|e| format!("Invalid server name: {e}"))?;
+    let ssl = connector
+        .configure()
+        .map_err(|e| format!("SSL configure: {e}"))?
+        .into_ssl(domain)
+        .map_err(|e| format!("SSL into_ssl: {e}"))?;
+
+    let mut stream = tokio_boring2::SslStream::new(ssl, tcp)
+        .map_err(|e| format!("SslStream::new for {domain}: {e}"))?;
 
     match tokio::time::timeout(
         std::time::Duration::from_secs(15),
-        connector.connect(server_name, tcp),
+        std::pin::Pin::new(&mut stream).connect(),
     )
     .await
     {
-        Ok(Ok(s)) => {
-            info!(domain, "MITM: upstream TLS connected ✓");
-            Ok(s)
+        Ok(Ok(())) => {
+            info!(domain, "MITM: upstream TLS connected ✓ (BoringSSL)");
+            Ok(stream)
         }
-        Ok(Err(e)) => Err(format!("TLS connect to upstream {domain}: {e}")),
+        Ok(Err(e)) => Err(format!("TLS handshake to upstream {domain}: {e}")),
         Err(_) => Err(format!("TLS connect to upstream {domain}: timed out")),
     }
 }

src/mitm/tls.rs

@@ -0,0 +1,86 @@
+//! Upstream TLS configuration matching Go's `crypto/tls` defaults.
+//!
+//! The LS is a Go binary — its outbound TLS to Google uses Go's default
+//! cipher suites, curves, and signature algorithms. This module configures
+//! BoringSSL to produce a matching TLS ClientHello so Google sees the same
+//! JA3/JA4 fingerprint regardless of whether our MITM is active.
+
+use boring2::ssl::{SslConnector, SslMethod};
+use tracing::debug;
+
+/// Go's default cipher suites in the exact order Go's `crypto/tls` sends them.
+///
+/// TLS 1.3 ciphers (hardcoded in Go, not configurable):
+///   TLS_AES_128_GCM_SHA256, TLS_AES_256_GCM_SHA384, TLS_CHACHA20_POLY1305_SHA256
+///
+/// TLS 1.2 ciphers (Go's default preference order):
+///   ECDHE-ECDSA-AES128-GCM-SHA256, ECDHE-RSA-AES128-GCM-SHA256,
+///   ECDHE-ECDSA-AES256-GCM-SHA384, ECDHE-RSA-AES256-GCM-SHA384,
+///   ECDHE-ECDSA-CHACHA20-POLY1305, ECDHE-RSA-CHACHA20-POLY1305,
+///   ECDHE-RSA-AES128-SHA, ECDHE-RSA-AES256-SHA,
+///   AES128-GCM-SHA256, AES256-GCM-SHA384, AES128-SHA, AES256-SHA
+const GO_CIPHER_LIST: &str = "\
+TLS_AES_128_GCM_SHA256:\
+TLS_AES_256_GCM_SHA384:\
+TLS_CHACHA20_POLY1305_SHA256:\
+ECDHE-ECDSA-AES128-GCM-SHA256:\
+ECDHE-RSA-AES128-GCM-SHA256:\
+ECDHE-ECDSA-AES256-GCM-SHA384:\
+ECDHE-RSA-AES256-GCM-SHA384:\
+ECDHE-ECDSA-CHACHA20-POLY1305:\
+ECDHE-RSA-CHACHA20-POLY1305:\
+ECDHE-RSA-AES128-SHA:\
+ECDHE-RSA-AES256-SHA:\
+AES128-GCM-SHA256:\
+AES256-GCM-SHA384:\
+AES128-SHA:\
+AES256-SHA";
+
+/// Go's default signature algorithms.
+const GO_SIGALGS: &str = "\
+ECDSA+SHA256:\
+RSA-PSS+SHA256:\
+RSA+SHA256:\
+ECDSA+SHA384:\
+RSA-PSS+SHA384:\
+RSA+SHA384:\
+RSA-PSS+SHA512:\
+RSA+SHA512:\
+RSA+SHA1";
+
+/// Build an `SslConnector` that mimics Go's `crypto/tls` defaults.
+///
+/// If `alpn` is provided, sets ALPN protocols (e.g. `&[b"h2"]` for HTTP/2).
+pub fn build_go_tls_connector(alpn: Option<&[&[u8]]>) -> SslConnector {
+    let mut builder =
+        SslConnector::builder(SslMethod::tls_client()).expect("SslConnector::builder");
+
+    // Set Go's cipher list
+    builder
+        .set_cipher_list(GO_CIPHER_LIST)
+        .expect("set_cipher_list");
+
+    // Set Go's signature algorithms
+    builder
+        .set_sigalgs_list(GO_SIGALGS)
+        .expect("set_sigalgs_list");
+
+    // Set Go's default curves: X25519, P-256, P-384
+    // BoringSSL uses set_curves_list with colon-separated names
+    builder
+        .set_curves_list("X25519:P-256:P-384")
+        .expect("set_curves_list");
+
+    // ALPN if requested (for HTTP/2)
+    if let Some(protos) = alpn {
+        let mut wire = Vec::new();
+        for proto in protos {
+            wire.push(proto.len() as u8);
+            wire.extend_from_slice(proto);
+        }
+        builder.set_alpn_protos(&wire).expect("set_alpn_protos");
+    }
+
+    debug!("Built Go-matching TLS connector (BoringSSL)");
+    builder.build()
+}

src/standalone/spawn.rs

@@ -275,22 +275,32 @@ impl StandaloneLS {
             // With iptables, all outbound traffic is transparently redirected at the
             // kernel level — setting HTTPS_PROXY on top causes double-proxying.
             if headless || !platform::supports_uid_isolation() {
-                // proxy_addr already includes the scheme (e.g. "http://127.0.0.1:8742")
-                env_vars.push(("HTTPS_PROXY".into(), mitm.proxy_addr.clone()));
-                env_vars.push(("HTTP_PROXY".into(), mitm.proxy_addr.clone()));
-
                 // LD_PRELOAD DNS redirect: hooks getaddrinfo() so Google API domains
                 // resolve to 127.0.0.1. Combined with the port-modified endpoint URL,
                 // this makes the LS connect to our MITM proxy for ALL API calls —
                 // even the CodeAssistClient which has Proxy:nil hardcoded.
                 let so_path = build_dns_redirect_so();
-                if let Some(so) = so_path {
+                if let Some(ref so) = so_path {
                     info!(path = %so, "Enabling LD_PRELOAD DNS redirect for headless MITM");
-                    env_vars.push(("LD_PRELOAD".into(), so));
+                    env_vars.push(("LD_PRELOAD".into(), so.clone()));
                     env_vars.push((
                         "DNS_REDIRECT_LOG".into(),
                         format!("{data_dir}/dns-redirect.log"),
                     ));
+                    // Force Go binaries to use cgo (libc) DNS resolver instead of
+                    // the pure-Go resolver. Without this, LD_PRELOAD getaddrinfo()
+                    // hooks are bypassed because Go resolves DNS internally.
+                    env_vars.push(("GODEBUG".into(), "netdns=cgo".into()));
+                }
+
+                // Only set HTTPS_PROXY as fallback when DNS redirect is NOT available.
+                // When DNS redirect IS active, HTTPS_PROXY is redundant and harmful:
+                // Go's net/http sends HTTP CONNECT through the proxy, but the MITM
+                // proxy expects direct TLS connections (SNI-based interception).
+                // This causes OAuth token refresh and other non-gRPC calls to fail.
+                if so_path.is_none() {
+                    env_vars.push(("HTTPS_PROXY".into(), mitm.proxy_addr.clone()));
+                    env_vars.push(("HTTP_PROXY".into(), mitm.proxy_addr.clone()));
                 }
             }
         }