diff --git a/src/main/daemon/binary-frame.test.ts b/src/main/daemon/binary-frame.test.ts
deleted file mode 100644
index 81148f18a59..00000000000
--- a/src/main/daemon/binary-frame.test.ts
+++ /dev/null
@@ -1,167 +0,0 @@
-import { describe, expect, it, vi } from 'vitest'
-import { encodeFrame, createFrameParser, FrameType, FRAME_HEADER_SIZE } from './binary-frame'
-
-describe('encodeFrame', () => {
-  it('encodes a data frame with correct header', () => {
-    const payload = Buffer.from('hello')
-    const frame = encodeFrame(FrameType.Data, payload)
-
-    expect(frame.length).toBe(FRAME_HEADER_SIZE + payload.length)
-    expect(frame[0]).toBe(FrameType.Data)
-    expect(frame.readUInt32BE(1)).toBe(payload.length)
-    expect(frame.subarray(FRAME_HEADER_SIZE).toString()).toBe('hello')
-  })
-
-  it('encodes a resize frame', () => {
-    const payload = Buffer.from(JSON.stringify({ cols: 120, rows: 40 }))
-    const frame = encodeFrame(FrameType.Resize, payload)
-
-    expect(frame[0]).toBe(FrameType.Resize)
-    expect(frame.readUInt32BE(1)).toBe(payload.length)
-  })
-
-  it('encodes an exit frame with exit code', () => {
-    const payload = Buffer.from(JSON.stringify({ code: 0 }))
-    const frame = encodeFrame(FrameType.Exit, payload)
-
-    expect(frame[0]).toBe(FrameType.Exit)
-    const decoded = JSON.parse(frame.subarray(FRAME_HEADER_SIZE).toString())
-    expect(decoded.code).toBe(0)
-  })
-
-  it('encodes empty payload', () => {
-    const frame = encodeFrame(FrameType.Kill, Buffer.alloc(0))
-
-    expect(frame.length).toBe(FRAME_HEADER_SIZE)
-    expect(frame[0]).toBe(FrameType.Kill)
-    expect(frame.readUInt32BE(1)).toBe(0)
-  })
-
-  it('throws on payload exceeding max size', () => {
-    const oversized = Buffer.alloc(1024 * 1024 + 1)
-    expect(() => encodeFrame(FrameType.Data, oversized)).toThrow()
-  })
-})
-
-describe('createFrameParser', () => {
-  it('parses a single complete frame', () => {
-    const onFrame = vi.fn()
-    const parser = createFrameParser(onFrame)
-
-    const payload = Buffer.from('test data')
-    const frame = encodeFrame(FrameType.Data, payload)
-    parser.feed(frame)
-
-    expect(onFrame).toHaveBeenCalledOnce()
-    expect(onFrame.mock.calls[0][0]).toBe(FrameType.Data)
-    expect(onFrame.mock.calls[0][1].toString()).toBe('test data')
-  })
-
-  it('parses multiple frames in one chunk', () => {
-    const onFrame = vi.fn()
-    const parser = createFrameParser(onFrame)
-
-    const frame1 = encodeFrame(FrameType.Data, Buffer.from('one'))
-    const frame2 = encodeFrame(FrameType.Data, Buffer.from('two'))
-    parser.feed(Buffer.concat([frame1, frame2]))
-
-    expect(onFrame).toHaveBeenCalledTimes(2)
-    expect(onFrame.mock.calls[0][1].toString()).toBe('one')
-    expect(onFrame.mock.calls[1][1].toString()).toBe('two')
-  })
-
-  it('handles frame split across header boundary', () => {
-    const onFrame = vi.fn()
-    const parser = createFrameParser(onFrame)
-
-    const payload = Buffer.from('split test')
-    const frame = encodeFrame(FrameType.Data, payload)
-
-    // Split in the middle of the header (3 bytes, then the rest)
-    parser.feed(frame.subarray(0, 3))
-    expect(onFrame).not.toHaveBeenCalled()
-
-    parser.feed(frame.subarray(3))
-    expect(onFrame).toHaveBeenCalledOnce()
-    expect(onFrame.mock.calls[0][1].toString()).toBe('split test')
-  })
-
-  it('handles frame split in the middle of payload', () => {
-    const onFrame = vi.fn()
-    const parser = createFrameParser(onFrame)
-
-    const payload = Buffer.from('payload split')
-    const frame = encodeFrame(FrameType.Data, payload)
-
-    // Split after header + 3 bytes of payload
-    const splitPoint = FRAME_HEADER_SIZE + 3
-    parser.feed(frame.subarray(0, splitPoint))
-    expect(onFrame).not.toHaveBeenCalled()
-
-    parser.feed(frame.subarray(splitPoint))
-    expect(onFrame).toHaveBeenCalledOnce()
-    expect(onFrame.mock.calls[0][1].toString()).toBe('payload split')
-  })
-
-  it('handles byte-by-byte feeding', () => {
-    const onFrame = vi.fn()
-    const parser = createFrameParser(onFrame)
-
-    const frame = encodeFrame(FrameType.Exit, Buffer.from('{"code":42}'))
-
-    for (let i = 0; i < frame.length; i++) {
-      parser.feed(frame.subarray(i, i + 1))
-    }
-
-    expect(onFrame).toHaveBeenCalledOnce()
-    expect(onFrame.mock.calls[0][0]).toBe(FrameType.Exit)
-    expect(JSON.parse(onFrame.mock.calls[0][1].toString())).toEqual({ code: 42 })
-  })
-
-  it('handles zero-length payload frame', () => {
-    const onFrame = vi.fn()
-    const parser = createFrameParser(onFrame)
-
-    const frame = encodeFrame(FrameType.Kill, Buffer.alloc(0))
-    parser.feed(frame)
-
-    expect(onFrame).toHaveBeenCalledOnce()
-    expect(onFrame.mock.calls[0][0]).toBe(FrameType.Kill)
-    expect(onFrame.mock.calls[0][1].length).toBe(0)
-  })
-
-  it('parses different frame types correctly', () => {
-    const onFrame = vi.fn()
-    const parser = createFrameParser(onFrame)
-
-    const frames = [
-      encodeFrame(FrameType.Data, Buffer.from('data')),
-      encodeFrame(FrameType.Resize, Buffer.from('resize')),
-      encodeFrame(FrameType.Signal, Buffer.from('signal'))
-    ]
-
-    parser.feed(Buffer.concat(frames))
-
-    expect(onFrame).toHaveBeenCalledTimes(3)
-    expect(onFrame.mock.calls[0][0]).toBe(FrameType.Data)
-    expect(onFrame.mock.calls[1][0]).toBe(FrameType.Resize)
-    expect(onFrame.mock.calls[2][0]).toBe(FrameType.Signal)
-  })
-
-  it('resets buffer state', () => {
-    const onFrame = vi.fn()
-    const parser = createFrameParser(onFrame)
-
-    // Feed partial frame then reset
-    const frame = encodeFrame(FrameType.Data, Buffer.from('lost'))
-    parser.feed(frame.subarray(0, 3))
-    parser.reset()
-
-    // Feed a new complete frame
-    const frame2 = encodeFrame(FrameType.Data, Buffer.from('fresh'))
-    parser.feed(frame2)
-
-    expect(onFrame).toHaveBeenCalledOnce()
-    expect(onFrame.mock.calls[0][1].toString()).toBe('fresh')
-  })
-})
diff --git a/src/main/daemon/binary-frame.ts b/src/main/daemon/binary-frame.ts
deleted file mode 100644
index e8c4fd6ae90..00000000000
--- a/src/main/daemon/binary-frame.ts
+++ /dev/null
@@ -1,56 +0,0 @@
-export { FrameType } from './types'
-import type { FrameType } from './types'
-import { FRAME_HEADER_SIZE, FRAME_MAX_PAYLOAD } from './types'
-
-export { FRAME_HEADER_SIZE }
-
-export function encodeFrame(type: FrameType, payload: Buffer): Buffer {
-  if (payload.length > FRAME_MAX_PAYLOAD) {
-    throw new Error(`Frame payload ${payload.length} exceeds max ${FRAME_MAX_PAYLOAD}`)
-  }
-
-  const frame = Buffer.allocUnsafe(FRAME_HEADER_SIZE + payload.length)
-  frame[0] = type
-  frame.writeUInt32BE(payload.length, 1)
-  payload.copy(frame, FRAME_HEADER_SIZE)
-  return frame
-}
-
-export type FrameParser = {
-  feed(chunk: Buffer): void
-  reset(): void
-}
-
-export function createFrameParser(
-  onFrame: (type: FrameType, payload: Buffer) => void
-): FrameParser {
-  let buffer: Buffer = Buffer.alloc(0)
-
-  function parse(): void {
-    while (buffer.length >= FRAME_HEADER_SIZE) {
-      const payloadLength = buffer.readUInt32BE(1)
-      const totalLength = FRAME_HEADER_SIZE + payloadLength
-
-      if (buffer.length < totalLength) {
-        break
-      }
-
-      const type = buffer[0] as FrameType
-      const payload = buffer.subarray(FRAME_HEADER_SIZE, totalLength)
-      buffer = buffer.subarray(totalLength)
-
-      onFrame(type, payload)
-    }
-  }
-
-  return {
-    feed(chunk: Buffer): void {
-      buffer = buffer.length === 0 ? chunk : Buffer.concat([buffer, chunk])
-      parse()
-    },
-
-    reset(): void {
-      buffer = Buffer.alloc(0)
-    }
-  }
-}
diff --git a/src/main/daemon/types.ts b/src/main/daemon/types.ts
index 865572ea0b1..1f067885467 100644
--- a/src/main/daemon/types.ts
+++ b/src/main/daemon/types.ts
@@ -383,23 +383,6 @@ export type DaemonSessionInfo = SessionInfo & {
 // existing importers keep one types entry point.
 export * from './daemon-stream-events'
 
-// ─── Binary Frame Protocol (Daemon ↔ PTY Subprocess) ────────────────
-//
-// 5-byte header: [type:1][length:4 big-endian]
-// Followed by `length` bytes of payload.
-
-export const enum FrameType {
-  Data = 0x01,
-  Resize = 0x02,
-  Exit = 0x03,
-  Error = 0x04,
-  Kill = 0x05,
-  Signal = 0x06
-}
-
-export const FRAME_HEADER_SIZE = 5
-export const FRAME_MAX_PAYLOAD = 1024 * 1024 // 1MB
-
 // ─── Notify prefix ──────────────────────────────────────────────────
 // Requests with IDs starting with this prefix are fire-and-forget:
 // the daemon processes them but does not send a response.