diff --git a/docs/languages/jupyter-notebook.md b/docs/languages/jupyter-notebook.md
new file mode 100644
index 000000000..c6b79090b
--- /dev/null
+++ b/docs/languages/jupyter-notebook.md
@@ -0,0 +1,38 @@
+# Jupyter notebook (.ipynb) indexing
+
+Status: implemented (Python code cells)
+
+GitNexus indexes Jupyter notebooks by extracting Python code cells and parsing them with the existing Python language provider. Notebooks are not executed.
+
+## Goal
+
+After `analyze`, functions, classes, and imports defined in Python code cells are queryable like ordinary `.py` files.
+
+## Compatibility
+
+- `.ipynb` is detected as Python (`gitnexus-shared` `EXTENSION_MAP` and `pythonProvider.extensions`).
+- Extraction lives in `gitnexus/src/core/ingestion/ipynb-extractor.ts`. Shared ingestion modules do not name nbformat AST types.
+- Notebooks are **not** Python import targets. A notebook may import `.py` modules; `import some_notebook` does not resolve to an `.ipynb`.
+- Files over the walker size cap (default 512KB, `GITNEXUS_MAX_FILE_SIZE`) are skipped like any other oversized file. Output-heavy notebooks may need a higher cap. Outputs are not stripped in this slice.
+- Group-layer FastAPI/Flask/Django scanners that require a `.py` suffix still ignore notebooks.
+
+## Kernel and magics
+
+- Skip the file when `kernelspec.language` or `language_info.name` is present and is not a Python-family name (`python`, `python2`, `python3`, `ipython`). Disagreeing fields skip the file.
+- If those fields are absent, code cells are treated as Python unless a cell's own language metadata says otherwise.
+- A cell whose first non-empty line is a cell magic (`%%`) is skipped.
+- Line magics (`%`) and shell (`!`) lines are commented in place so JSON line mapping stays affine.
+
+## Line numbers
+
+Graph `startLine` / `endLine` are 0-based coordinates in the on-disk `.ipynb` JSON. FTS/MCP symbol snippets reconstruct cell Python; they do not slice raw JSON.
+
+Concatenating cells in document order is notebook semantics. An earlier cell with a syntax error may cause later definitions to be missed; that is a documented limitation, not a per-cell fallback parse.
+
+## Tests
+
+- `gitnexus/test/unit/ipynb-extractor.test.ts`
+- `gitnexus/test/unit/ingestion-utils.test.ts` (`.ipynb` detection)
+- `gitnexus/test/integration/ipynb-python-pipeline.test.ts`
+
+No Jupyter, nbconvert, or nbformat runtime dependency.
diff --git a/gitnexus-shared/src/language-detection.ts b/gitnexus-shared/src/language-detection.ts
index 3fe27f7b7..b17c1d629 100644
--- a/gitnexus-shared/src/language-detection.ts
+++ b/gitnexus-shared/src/language-detection.ts
@@ -29,7 +29,7 @@ const RUBY_EXTENSIONLESS_FILES = new Set([
 const EXTENSION_MAP: Record<SupportedLanguages, readonly string[]> = {
   [SupportedLanguages.JavaScript]: ['.js', '.jsx', '.mjs', '.cjs'],
   [SupportedLanguages.TypeScript]: ['.ts', '.tsx', '.mts', '.cts'],
-  [SupportedLanguages.Python]: ['.py'],
+  [SupportedLanguages.Python]: ['.py', '.ipynb'],
   [SupportedLanguages.Java]: ['.java'],
   [SupportedLanguages.C]: ['.c'],
   [SupportedLanguages.ObjectiveC]: ['.m', '.mm'],
diff --git a/gitnexus/src/core/embeddings/ast-utils.ts b/gitnexus/src/core/embeddings/ast-utils.ts
index b29ca80fb..3e393f2c1 100644
--- a/gitnexus/src/core/embeddings/ast-utils.ts
+++ b/gitnexus/src/core/embeddings/ast-utils.ts
@@ -11,6 +11,7 @@ import {
 } from '../tree-sitter/parser-loader.js';
 import { parseSourceSafe } from '../tree-sitter/safe-parse.js';
 import { getLanguageForFileContent, getProvider } from '../ingestion/languages/index.js';
+import { extractNotebookPython } from '../ingestion/ipynb-extractor.js';
 
 const parserCache = new Map<string, any>();
 
@@ -39,7 +40,13 @@ export const ensureAndParse = async (content: string, filePath: string): Promise
   // error-recovered tree. Resolved from `language` so the transform and the
   // parser always come from the same provider. Length-preserving, so node
   // offsets still index `content`.
-  const parseContent = getProvider(language).preprocessSource?.(content, filePath) ?? content;
+  let parseContent = getProvider(language).preprocessSource?.(content, filePath) ?? content;
+  if (filePath.replace(/\\/g, '/').toLowerCase().endsWith('.ipynb')) {
+    const extracted = extractNotebookPython(content);
+    if (!extracted) return null;
+    parseContent = getProvider(language).preprocessSource?.(extracted.pythonSource, filePath) ??
+      extracted.pythonSource;
+  }
 
   return parseSourceSafe(parserInstance, parseContent);
 };
diff --git a/gitnexus/src/core/ingestion/cfg/collect.ts b/gitnexus/src/core/ingestion/cfg/collect.ts
index bdf1b095d..62d20ecb6 100644
--- a/gitnexus/src/core/ingestion/cfg/collect.ts
+++ b/gitnexus/src/core/ingestion/cfg/collect.ts
@@ -83,12 +83,30 @@ function shiftCfgLines(cfg: FunctionCfg, offset: number): FunctionCfg {
   };
 }
 
+function remapCfgLines(cfg: FunctionCfg, mapLine: (row: number) => number): FunctionCfg {
+  return {
+    ...cfg,
+    functionStartLine: mapLine(cfg.functionStartLine),
+    functionEndLine: mapLine(cfg.functionEndLine),
+    blocks: cfg.blocks.map((b) => ({
+      ...b,
+      startLine: mapLine(b.startLine),
+      endLine: mapLine(b.endLine),
+      statements: b.statements?.map((s) => ({ ...s, line: mapLine(s.line) })),
+    })),
+    bindings: cfg.bindings?.map((bd) =>
+      bd.declLine > 0 ? { ...bd, declLine: mapLine(bd.declLine) } : bd,
+    ),
+  };
+}
+
 export function collectFunctionCfgs(
   root: SyntaxNode,
   visitor: CfgVisitor<SyntaxNode>,
   filePath: string,
   maxFunctionLines = 0,
   lineOffset = 0,
+  mapLine?: (row: number) => number,
 ): CollectedCfgs {
   const cfgs: FunctionCfg[] = [];
   let tooManyLines = 0;
@@ -109,7 +127,9 @@ export function collectFunctionCfgs(
         // and silently drop every remaining function's CFG (#2195).
         try {
           const cfg = visitor.buildFunctionCfg(node, filePath);
-          if (cfg) cfgs.push(shiftCfgLines(cfg, lineOffset));
+          if (cfg) {
+            cfgs.push(mapLine ? remapCfgLines(cfg, mapLine) : shiftCfgLines(cfg, lineOffset));
+          }
         } catch (err) {
           if (err instanceof CfgNestingDepthError) tooDeeplyNested++;
           else buildError++;
diff --git a/gitnexus/src/core/ingestion/ipynb-extractor.ts b/gitnexus/src/core/ingestion/ipynb-extractor.ts
new file mode 100644
index 000000000..65486a4de
--- /dev/null
+++ b/gitnexus/src/core/ingestion/ipynb-extractor.ts
@@ -0,0 +1,298 @@
+/**
+ * Jupyter notebook (.ipynb) Python extractor.
+ *
+ * Pulls code-cell source from nbformat JSON so the Python tree-sitter
+ * grammar can parse it. Pure — no I/O, no tree-sitter, worker-safe.
+ *
+ * Graph coordinates stay 0-based lines in the on-disk JSON file. Extract
+ * buffer lines map through {@link mapExtractLine}.
+ */
+
+export interface NotebookLineSegment {
+  readonly extractStartLine: number;
+  readonly extractEndLine: number;
+  readonly jsonStartLine: number;
+  readonly jsonEndLine: number;
+}
+
+export interface NotebookPythonExtraction {
+  readonly pythonSource: string;
+  readonly segments: readonly NotebookLineSegment[];
+}
+
+const PYTHON_FAMILY = new Set(['python', 'python2', 'python3', 'ipython']);
+
+export function isPythonFamilyLanguage(name: string | undefined | null): boolean {
+  if (name === undefined || name === null) return false;
+  const n = name.trim().toLowerCase();
+  if (PYTHON_FAMILY.has(n)) return true;
+  return /^python\d/.test(n);
+}
+
+function indexToLine(content: string, index: number): number {
+  let line = 0;
+  const end = Math.max(0, Math.min(index, content.length));
+  for (let i = 0; i < end; i++) {
+    if (content.charCodeAt(i) === 10) line++;
+  }
+  return line;
+}
+
+function skipWs(content: string, i: number): number {
+  while (i < content.length) {
+    const c = content.charCodeAt(i);
+    if (c === 32 || c === 9 || c === 10 || c === 13) i++;
+    else break;
+  }
+  return i;
+}
+
+/** Span of a JSON string or array value starting at the first `"` or `[`. */
+function jsonValueSpan(content: string, start: number): { start: number; end: number } | null {
+  const i = skipWs(content, start);
+  if (i >= content.length) return null;
+  if (content[i] === '"') {
+    let j = i + 1;
+    while (j < content.length) {
+      if (content[j] === '\\') {
+        j += 2;
+        continue;
+      }
+      if (content[j] === '"') return { start: i, end: j + 1 };
+      j++;
+    }
+    return null;
+  }
+  if (content[i] === '[') {
+    let depth = 1;
+    let j = i + 1;
+    let inStr = false;
+    while (j < content.length && depth > 0) {
+      const ch = content[j];
+      if (inStr) {
+        if (ch === '\\') j += 2;
+        else {
+          if (ch === '"') inStr = false;
+          j++;
+        }
+        continue;
+      }
+      if (ch === '"') inStr = true;
+      else if (ch === '[') depth++;
+      else if (ch === ']') depth--;
+      j++;
+    }
+    return { start: i, end: j };
+  }
+  return null;
+}
+
+function findNextCodeCellSourceSpan(
+  content: string,
+  from: number,
+): { span: { start: number; end: number }; nextFrom: number } | null {
+  let search = from;
+  while (search < content.length) {
+    const typeKey = content.indexOf('"cell_type"', search);
+    if (typeKey < 0) return null;
+    const colon = content.indexOf(':', typeKey + 11);
+    if (colon < 0) return null;
+    const valueStart = skipWs(content, colon + 1);
+    if (content.slice(valueStart, valueStart + 6) !== '"code"') {
+      search = typeKey + 11;
+      continue;
+    }
+    const sourceKey = content.indexOf('"source"', valueStart);
+    if (sourceKey < 0) return null;
+    const srcColon = content.indexOf(':', sourceKey + 8);
+    if (srcColon < 0) return null;
+    const span = jsonValueSpan(content, srcColon + 1);
+    if (!span) return null;
+    return { span, nextFrom: span.end };
+  }
+  return null;
+}
+
+function flattenSource(source: unknown): string {
+  if (typeof source === 'string') return source;
+  if (Array.isArray(source)) {
+    return source.map((part) => (typeof part === 'string' ? part : '')).join('');
+  }
+  return '';
+}
+
+function cellLanguage(cell: Record<string, unknown>): string | undefined {
+  const meta = cell.metadata;
+  if (!meta || typeof meta !== 'object') return undefined;
+  const m = meta as Record<string, unknown>;
+  if (typeof m.language === 'string') return m.language;
+  const vscode = m.vscode;
+  if (vscode && typeof vscode === 'object') {
+    const langId = (vscode as Record<string, unknown>).languageId;
+    if (typeof langId === 'string') return langId;
+  }
+  return undefined;
+}
+
+function notebookLanguageFields(nb: Record<string, unknown>): {
+  kernelspec?: string;
+  languageInfo?: string;
+} {
+  const metadata = nb.metadata;
+  if (!metadata || typeof metadata !== 'object') return {};
+  const md = metadata as Record<string, unknown>;
+  const ks = md.kernelspec;
+  const li = md.language_info;
+  return {
+    kernelspec:
+      ks && typeof ks === 'object' && typeof (ks as Record<string, unknown>).language === 'string'
+        ? String((ks as Record<string, unknown>).language)
+        : undefined,
+    languageInfo:
+      li && typeof li === 'object' && typeof (li as Record<string, unknown>).name === 'string'
+        ? String((li as Record<string, unknown>).name)
+        : undefined,
+  };
+}
+
+function kernelShouldSkip(nb: Record<string, unknown>): boolean {
+  const { kernelspec, languageInfo } = notebookLanguageFields(nb);
+  const fields = [kernelspec, languageInfo].filter((x): x is string => x !== undefined);
+  if (fields.length === 0) return false;
+  if (fields.some((f) => !isPythonFamilyLanguage(f))) return true;
+  if (fields.length === 2 && fields[0].toLowerCase() !== fields[1].toLowerCase()) {
+    const a = isPythonFamilyLanguage(fields[0]);
+    const b = isPythonFamilyLanguage(fields[1]);
+    if (a !== b) return true;
+  }
+  return false;
+}
+
+function processCellLines(raw: string): { skipCell: boolean; lines: string[] } {
+  const lines = raw.split('\n');
+  const firstNonEmpty = lines.find((l) => l.trim().length > 0);
+  if (firstNonEmpty !== undefined && firstNonEmpty.trimStart().startsWith('%%')) {
+    return { skipCell: true, lines: [''] };
+  }
+  const out = lines.map((line) => {
+    const t = line.trimStart();
+    if (t.startsWith('%') || t.startsWith('!')) {
+      return `# ${line}`;
+    }
+    return line;
+  });
+  return { skipCell: false, lines: out };
+}
+
+export function extractNotebookPython(content: string): NotebookPythonExtraction | null {
+  let parsed: unknown;
+  try {
+    parsed = JSON.parse(content);
+  } catch {
+    return null;
+  }
+  if (!parsed || typeof parsed !== 'object') return null;
+  const nb = parsed as Record<string, unknown>;
+  if (!Array.isArray(nb.cells)) return null;
+  if (kernelShouldSkip(nb)) return null;
+
+  const chunks: string[] = [];
+  const segments: NotebookLineSegment[] = [];
+  let extractLine = 0;
+  let searchFrom = 0;
+  let codeCellIndex = 0;
+
+  for (const rawCell of nb.cells) {
+    if (!rawCell || typeof rawCell !== 'object') continue;
+    const cell = rawCell as Record<string, unknown>;
+    if (cell.cell_type !== 'code') continue;
+
+    const located = findNextCodeCellSourceSpan(content, searchFrom);
+    if (!located) return null;
+    searchFrom = located.nextFrom;
+    codeCellIndex++;
+
+    const lang = cellLanguage(cell);
+    if (lang !== undefined && !isPythonFamilyLanguage(lang)) {
+      continue;
+    }
+
+    const { skipCell, lines } = processCellLines(flattenSource(cell.source));
+    const jsonStartLine = indexToLine(content, located.span.start);
+    const jsonEndLine = Math.max(jsonStartLine, indexToLine(content, located.span.end - 1));
+
+    if (skipCell) {
+      continue;
+    }
+
+    const text = lines.join('\n');
+    if (text.trim().length === 0) {
+      chunks.push('');
+      const start = extractLine;
+      extractLine += 1;
+      segments.push({
+        extractStartLine: start,
+        extractEndLine: start,
+        jsonStartLine,
+        jsonEndLine,
+      });
+      continue;
+    }
+
+    if (chunks.length > 0) {
+      chunks.push('\n');
+      extractLine += 1;
+    }
+    const extractStartLine = extractLine;
+    chunks.push(text);
+    const addedLines = text.split('\n').length;
+    extractLine += addedLines;
+    segments.push({
+      extractStartLine,
+      extractEndLine: extractLine - 1,
+      jsonStartLine,
+      jsonEndLine,
+    });
+  }
+
+  void codeCellIndex;
+  const pythonSource = chunks.join('');
+  if (pythonSource.trim().length === 0) return null;
+  return { pythonSource, segments };
+}
+
+export function mapExtractLine(row: number, segments: readonly NotebookLineSegment[]): number {
+  if (segments.length === 0) return row;
+  for (const seg of segments) {
+    if (row >= seg.extractStartLine && row <= seg.extractEndLine) {
+      const delta = row - seg.extractStartLine;
+      const jsonSpan = seg.jsonEndLine - seg.jsonStartLine;
+      return seg.jsonStartLine + Math.min(delta, jsonSpan);
+    }
+  }
+  if (row < segments[0].extractStartLine) return segments[0].jsonStartLine;
+  const last = segments[segments.length - 1];
+  return last.jsonEndLine;
+}
+
+/** Python snippet for a graph span stored in JSON file coordinates. */
+export function notebookPythonSnippet(
+  fileContent: string,
+  startLine: number,
+  endLine: number,
+): string | null {
+  const extracted = extractNotebookPython(fileContent);
+  if (!extracted) return null;
+  const pyLines = extracted.pythonSource.split('\n');
+  const out: string[] = [];
+  for (const seg of extracted.segments) {
+    for (let extract = seg.extractStartLine; extract <= seg.extractEndLine; extract++) {
+      const jsonLine = mapExtractLine(extract, extracted.segments);
+      if (jsonLine >= startLine && jsonLine <= endLine) {
+        out.push(pyLines[extract] ?? '');
+      }
+    }
+  }
+  if (out.length === 0) return null;
+  return out.join('\n');
+}
diff --git a/gitnexus/src/core/ingestion/languages/python.ts b/gitnexus/src/core/ingestion/languages/python.ts
index ce8d0fa90..d07902f66 100644
--- a/gitnexus/src/core/ingestion/languages/python.ts
+++ b/gitnexus/src/core/ingestion/languages/python.ts
@@ -107,7 +107,7 @@ function normalizePythonStringLiteral(text: string): string | undefined {
 
 export const pythonProvider = defineLanguage({
   id: SupportedLanguages.Python,
-  extensions: ['.py'],
+  extensions: ['.py', '.ipynb'],
   entryPointPatterns: [/^app$/, /^(get|post|put|delete|patch)_/i, /^api_/, /^view_/],
   astFrameworkPatterns: [
     {
diff --git a/gitnexus/src/core/ingestion/languages/python/captures.ts b/gitnexus/src/core/ingestion/languages/python/captures.ts
index a6d19fdc4..1ae0cfdb2 100644
--- a/gitnexus/src/core/ingestion/languages/python/captures.ts
+++ b/gitnexus/src/core/ingestion/languages/python/captures.ts
@@ -24,6 +24,7 @@ import {
 } from '../../utils/ast-helpers.js';
 import { splitImportStatement } from './import-decomposer.js';
 import { getPythonParser, getPythonScopeQuery } from './query.js';
+import { extractNotebookPython } from '../../ipynb-extractor.js';
 import {
   synthesizeConstructorFieldTypeBindings,
   synthesizeReceiverTypeBinding,
@@ -57,23 +58,34 @@ const PYTHON_CALLABLE_CAPTURE_OPTIONS = {
 
 export function emitPythonScopeCaptures(
   sourceText: string,
-  _filePath: string,
+  filePath: string,
   cachedTree?: unknown,
+  sourceMeta?: { sourceKind?: 'full-file' | 'pre-extracted-script' },
 ): readonly CaptureMatch[] {
+  let parseText = sourceText;
+  let tree = cachedTree as ReturnType<ReturnType<typeof getPythonParser>['parse']> | undefined;
+  if (
+    filePath.replace(/\\/g, '/').toLowerCase().endsWith('.ipynb') &&
+    sourceMeta?.sourceKind !== 'pre-extracted-script'
+  ) {
+    const extracted = extractNotebookPython(sourceText);
+    if (extracted === null) return [];
+    parseText = extracted.pythonSource;
+    tree = undefined;
+  }
   // Skip the parse when the caller (the scope-resolution orchestrator's
   // `treeCache`) already produced a Tree for this source — empty under
   // worker-pool runs, so cache miss = re-parse. The cachedTree parameter
   // is typed as `unknown` at the
   // contract layer (see `LanguageProvider.emitScopeCaptures`); cast
   // here at the use site.
-  let tree = cachedTree as ReturnType<ReturnType<typeof getPythonParser>['parse']> | undefined;
   if (tree === undefined) {
     try {
-      tree = parseSourceSafe(getPythonParser(), sourceText, undefined, {
-        bufferSize: getTreeSitterBufferSize(sourceText),
+      tree = parseSourceSafe(getPythonParser(), parseText, undefined, {
+        bufferSize: getTreeSitterBufferSize(parseText),
       });
     } catch (err) {
-      throw scopeExtractionError('parse', _filePath, err);
+      throw scopeExtractionError('parse', filePath, err);
     }
     recordCacheMiss();
   } else {
@@ -84,7 +96,7 @@ export function emitPythonScopeCaptures(
   try {
     rawMatches = getPythonScopeQuery().matches(tree.rootNode);
   } catch (err) {
-    throw scopeExtractionError('scope query', _filePath, err);
+    throw scopeExtractionError('scope query', filePath, err);
   }
 
   const out: CaptureMatch[] = [];
diff --git a/gitnexus/src/core/ingestion/workers/parse-worker.ts b/gitnexus/src/core/ingestion/workers/parse-worker.ts
index 1145b38e7..9a2c6d1e6 100644
--- a/gitnexus/src/core/ingestion/workers/parse-worker.ts
+++ b/gitnexus/src/core/ingestion/workers/parse-worker.ts
@@ -135,6 +135,11 @@ import {
   extractTemplateComponents,
   isVueSetupTopLevel,
 } from '../vue-sfc-extractor.js';
+import {
+  extractNotebookPython,
+  mapExtractLine,
+  type NotebookLineSegment,
+} from '../ipynb-extractor.js';
 import type { NodeLabel, ParameterTypeClass } from 'gitnexus-shared';
 import type { FieldInfo, FieldExtractorContext } from '../field-types.js';
 import type { MethodInfo, MethodExtractorContext } from '../method-types.js';
@@ -1597,6 +1602,9 @@ const processFileGroup = (
     let scopeSourceKind: ScopeCaptureSourceKind = 'full-file';
     let lineOffset = 0;
     let isVueSetup = false;
+    let notebookSegments: readonly NotebookLineSegment[] | undefined;
+    const mapRow = (row: number): number =>
+      notebookSegments ? mapExtractLine(row, notebookSegments) : row + lineOffset;
     if (language === SupportedLanguages.Vue) {
       const extracted = extractVueScript(file.content);
       if (!extracted) continue; // skip .vue files with no script block
@@ -1604,6 +1612,15 @@ const processFileGroup = (
       scopeSourceKind = 'pre-extracted-script';
       lineOffset = extracted.lineOffset;
       isVueSetup = extracted.isSetup;
+    } else if (
+      language === SupportedLanguages.Python &&
+      file.path.replace(/\\/g, '/').toLowerCase().endsWith('.ipynb')
+    ) {
+      const extracted = extractNotebookPython(file.content);
+      if (!extracted) continue;
+      parseContent = extracted.pythonSource;
+      scopeSourceKind = 'pre-extracted-script';
+      notebookSegments = extracted.segments;
     }
 
     // Per-language source-text transform (e.g., UE macro stripping for C++).
@@ -1722,6 +1739,7 @@ const processFileGroup = (
             // `lineOffset` in the file — shift the CFG into file coordinates so
             // it joins its graph node and BasicBlock lines map to source.
             lineOffset,
+            notebookSegments ? mapRow : undefined,
           );
           if (cfgs.length) withChannels = { ...withChannels, cfgSideChannel: cfgs };
           // Surface per-function CFG skips per-language (#2195): merged + logged
@@ -2483,10 +2501,10 @@ const processFileGroup = (
           : definitionNode?.startPosition;
       const startLine =
         startPosition !== undefined
-          ? startPosition.row + lineOffset
+          ? mapRow(startPosition.row)
           : nameNode
-            ? nameNode.startPosition.row + lineOffset
-            : lineOffset;
+            ? mapRow(nameNode.startPosition.row)
+            : mapRow(0);
       const startColumn = startPosition?.column ?? nameNode?.startPosition.column ?? 0;
 
       // Compute enclosing class BEFORE node ID — needed to qualify method IDs
@@ -2958,7 +2976,7 @@ const processFileGroup = (
                 filePath: file.path,
                 toolName: nodeName,
                 description: (dec.arg || description || '').slice(0, 200),
-                lineNumber: definitionNode.startPosition.row + lineOffset,
+                lineNumber: mapRow(definitionNode.startPosition.row),
                 handlerNodeId: nodeId,
               });
             }
@@ -3063,7 +3081,7 @@ const processFileGroup = (
           (objectLiteralBindingInfo?.ownerName || isArrayContainedObjectCallable)
             ? { startColumn }
             : {}),
-          endLine: definitionNode ? definitionNode.endPosition.row + lineOffset : startLine,
+          endLine: definitionNode ? mapRow(definitionNode.endPosition.row) : startLine,
           language: language,
           isExported,
           ...(qualifiedTypeName !== undefined ? { qualifiedName: qualifiedTypeName } : {}),
diff --git a/gitnexus/src/core/lbug/csv-generator.ts b/gitnexus/src/core/lbug/csv-generator.ts
index 5e652319c..fdfd6ecc8 100644
--- a/gitnexus/src/core/lbug/csv-generator.ts
+++ b/gitnexus/src/core/lbug/csv-generator.ts
@@ -23,6 +23,7 @@ import { VALID_NODE_TABLES, parseRelationSchemaPairs, RelPairRouter } from './re
 import { parseTruthyEnv } from '../ingestion/utils/env.js';
 import { SYMBOL_NODE_LABELS } from '../ingestion/utils/symbol-labels.js';
 import { applyCjkSegmentationIfEnabled } from '../search/cjk-segmentation.js';
+import { notebookPythonSnippet } from '../ingestion/ipynb-extractor.js';
 
 /** Computed once — `RELATION_SCHEMA` is a static template literal. Exported so
  *  the streamed sinks (`GraphEmitSink`, `PdgEmitSink`) share this parse
@@ -325,6 +326,21 @@ const extractContent = async (
   const endLine = node.properties.endLine;
   if (startLine === undefined || endLine === undefined) return '';
 
+  const notebookPath = String(filePath ?? '')
+    .replace(/\\/g, '/')
+    .toLowerCase();
+  if (notebookPath.endsWith('.ipynb')) {
+    const reconstructed = notebookPythonSnippet(content, startLine, endLine);
+    if (reconstructed) {
+      const MAX_SNIPPET = 5000;
+      const capped =
+        reconstructed.length > MAX_SNIPPET
+          ? reconstructed.slice(0, MAX_SNIPPET) + '\n... [truncated]'
+          : reconstructed;
+      return normalizeFtsText(applyCjkSegmentationIfEnabled(capped));
+    }
+  }
+
   const lines = prepared.lines;
   const exactSymbolContent = EXACT_SYMBOL_CONTENT_LABELS.has(node.label);
   const start = Math.max(0, exactSymbolContent ? startLine : startLine - 2);
diff --git a/gitnexus/src/storage/parse-cache.ts b/gitnexus/src/storage/parse-cache.ts
index 7e91cee4c..2c95bfb69 100644
--- a/gitnexus/src/storage/parse-cache.ts
+++ b/gitnexus/src/storage/parse-cache.ts
@@ -778,7 +778,12 @@ import { copyV8CacheIfPresent, tryLoadV8Cache, writeV8CacheFile } from './v8-sid
 // v104 (#3339 review): TS/JS pair-HOC queries now name object-pair
 // `mutation(withAuth(arrow))` handlers. Warm caches replay the pre-fix
 // capture set (anonymous arrows, no Function name), so both stores re-extract.
-const SCHEMA_BUMP = 104;
+// v104 (#3339 review): TS/JS pair-HOC queries now name object-pair
+// `mutation(withAuth(arrow))` handlers. Warm caches replay the pre-fix
+// capture set (anonymous arrows, no Function name), so both stores re-extract.
+// v105 (#3371): `.ipynb` code cells are extracted to Python before parse.
+// Warm caches keyed on raw JSON would replay empty/failed Python parses.
+const SCHEMA_BUMP = 105;
 const GITNEXUS_PKG_VERSION = (() => {
   try {
     // package.json sits at gitnexus/package.json — two levels up from
diff --git a/gitnexus/test/integration/resolvers/ipynb-python-pipeline.test.ts b/gitnexus/test/integration/resolvers/ipynb-python-pipeline.test.ts
new file mode 100644
index 000000000..ffb2070d4
--- /dev/null
+++ b/gitnexus/test/integration/resolvers/ipynb-python-pipeline.test.ts
@@ -0,0 +1,84 @@
+/**
+ * Jupyter notebooks are indexed as Python by extracting code cells.
+ */
+import { describe, it, expect } from 'vitest';
+import path from 'path';
+import fs from 'node:fs';
+import os from 'node:os';
+import {
+  getNodesByLabel,
+  getNodesByLabelFull,
+  getRelationships,
+  runPipelineFromRepo,
+  writeFixtureRepo,
+} from './helpers.js';
+
+function pythonNotebook(cells: Array<{ source: string | string[]; language?: string }>): string {
+  return JSON.stringify(
+    {
+      nbformat: 4,
+      nbformat_minor: 5,
+      metadata: {
+        kernelspec: { display_name: 'Python 3', language: 'python', name: 'python3' },
+        language_info: { name: 'python' },
+      },
+      cells: cells.map((c) => ({
+        cell_type: 'code',
+        metadata: c.language ? { language: c.language } : {},
+        source: c.source,
+        outputs: [],
+      })),
+    },
+    null,
+    2,
+  );
+}
+
+describe('Jupyter notebook Python pipeline', () => {
+  it('indexes notebook functions, imports sibling py, and skip-fails closed', async () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), 'gn-ipynb-'));
+    try {
+      writeFixtureRepo(root, {
+        'lib.py': 'def helper():\n    return 1\n',
+        'analysis.ipynb': pythonNotebook([
+          { source: ['from lib import helper\n'] },
+          { source: ['def train():\n', '    return helper()\n'] },
+        ]),
+        'broken.ipynb': '{not json',
+        'julia.ipynb': JSON.stringify({
+          nbformat: 4,
+          nbformat_minor: 5,
+          metadata: {
+            kernelspec: { language: 'julia', name: 'julia', display_name: 'Julia' },
+          },
+          cells: [
+            { cell_type: 'code', metadata: {}, source: ['function train() end\n'], outputs: [] },
+          ],
+        }),
+      });
+      const result = await runPipelineFromRepo(root, () => {}, { skipGraphPhases: true });
+      const functions = getNodesByLabel(result, 'Function');
+      expect(functions).toContain('train');
+      expect(functions).toContain('helper');
+      const train = getNodesByLabelFull(result, 'Function').find((n) => n.name === 'train');
+      expect(train?.properties.filePath.replace(/\\/g, '/')).toMatch(/analysis\.ipynb$/);
+      expect(train?.properties.startLine).toBeGreaterThan(0);
+      const imports = getRelationships(result, 'IMPORTS');
+      expect(
+        imports.some(
+          (e) =>
+            e.sourceFilePath.replace(/\\/g, '/').endsWith('analysis.ipynb') &&
+            (e.target === 'helper' || e.targetFilePath.replace(/\\/g, '/').endsWith('lib.py')),
+        ),
+      ).toBe(true);
+      expect(
+        getNodesByLabelFull(result, 'Function').filter(
+          (n) =>
+            n.properties.filePath.replace(/\\/g, '/').endsWith('julia.ipynb') && n.name === 'train',
+        ),
+      ).toHaveLength(0);
+    } finally {
+      fs.rmSync(root, { recursive: true, force: true });
+    }
+  }, 60000);
+});
diff --git a/gitnexus/test/unit/incremental-parse-cache.test.ts b/gitnexus/test/unit/incremental-parse-cache.test.ts
index 879af7a38..cbf77be34 100644
--- a/gitnexus/test/unit/incremental-parse-cache.test.ts
+++ b/gitnexus/test/unit/incremental-parse-cache.test.ts
@@ -288,8 +288,12 @@ describe('PARSE_CACHE_VERSION', () => {
   // Moved 103 -> 104 for #3339 review: pair-HOC queries name
   // `mutation(withAuth(arrow))` object-pair handlers. Warm caches replay
   // anonymous arrows, so both stores re-extract.
-  it('pins SCHEMA_BUMP to 104 so concurrent bumps cannot silently collide (#2766, #3015, #3088, #2885, #3128, #2865, #3130, #1432, #3161, #3179, #3219, #3190, #3253, #3273, #3339)', () => {
-    expect(Number(PARSE_CACHE_VERSION.split('+', 1)[0])).toBe(104);
+  // Moved 103 -> 104 for #3339 review: pair-HOC queries name
+  // `mutation(withAuth(arrow))` object-pair handlers. Warm caches replay
+  // anonymous arrows, so both stores re-extract.
+  // Moved 104 -> 105 for #3371: notebook code-cell extraction before Python parse.
+  it('pins SCHEMA_BUMP to 105 so concurrent bumps cannot silently collide (#2766, #3015, #3088, #2885, #3128, #2865, #3130, #1432, #3161, #3179, #3219, #3190, #3253, #3273, #3339, #3371)', () => {
+    expect(Number(PARSE_CACHE_VERSION.split('+', 1)[0])).toBe(105);
     expect(PARSE_CACHE_BUCKET_COUNT).toBe(128);
     // The PREVIOUS version must fail the reuse gate, not merely differ from the
     // current one — a hardcoded number outside the conflict hunk rebases cleanly
@@ -298,6 +302,7 @@ describe('PARSE_CACHE_VERSION', () => {
     for (const taken of [
       59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81,
       82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103,
+      104,
     ]) {
       expect(Number(PARSE_CACHE_VERSION.split('+', 1)[0])).not.toBe(taken);
     }
diff --git a/gitnexus/test/unit/ingestion-utils.test.ts b/gitnexus/test/unit/ingestion-utils.test.ts
index db16bfd34..79605d024 100644
--- a/gitnexus/test/unit/ingestion-utils.test.ts
+++ b/gitnexus/test/unit/ingestion-utils.test.ts
@@ -50,6 +50,11 @@ describe('getLanguageFromFilename', () => {
     it('detects .py files', () => {
       expect(getLanguageFromFilename('main.py')).toBe(SupportedLanguages.Python);
     });
+
+    it('detects .ipynb files as Python', () => {
+      expect(getLanguageFromFilename('analysis.ipynb')).toBe(SupportedLanguages.Python);
+      expect(getProviderForFile('notebooks/analysis.ipynb')?.id).toBe(SupportedLanguages.Python);
+    });
   });
 
   describe('Java', () => {
diff --git a/gitnexus/test/unit/ipynb-extractor.test.ts b/gitnexus/test/unit/ipynb-extractor.test.ts
new file mode 100644
index 000000000..23c48a94f
--- /dev/null
+++ b/gitnexus/test/unit/ipynb-extractor.test.ts
@@ -0,0 +1,213 @@
+import { describe, it, expect } from 'vitest';
+import {
+  extractNotebookPython,
+  mapExtractLine,
+  notebookPythonSnippet,
+  isPythonFamilyLanguage,
+} from '../../src/core/ingestion/ipynb-extractor.js';
+
+function notebook(opts: {
+  language?: string;
+  languageInfo?: string;
+  cells: Array<Record<string, unknown>>;
+}): string {
+  const kernelspec =
+    opts.language === undefined
+      ? undefined
+      : { display_name: 'Python', language: opts.language, name: 'python' };
+  const language_info =
+    opts.languageInfo === undefined ? undefined : { name: opts.languageInfo };
+  return JSON.stringify(
+    {
+      nbformat: 4,
+      nbformat_minor: 5,
+      metadata: {
+        ...(kernelspec ? { kernelspec } : {}),
+        ...(language_info ? { language_info } : {}),
+      },
+      cells: opts.cells,
+    },
+    null,
+    2,
+  );
+}
+
+describe('isPythonFamilyLanguage', () => {
+  it('accepts python3 and ipython', () => {
+    expect(isPythonFamilyLanguage('python3')).toBe(true);
+    expect(isPythonFamilyLanguage('IPython')).toBe(true);
+    expect(isPythonFamilyLanguage('julia')).toBe(false);
+  });
+});
+
+describe('extractNotebookPython', () => {
+  it('extracts def train from a Python v4 notebook', () => {
+    const content = notebook({
+      language: 'python',
+      cells: [
+        {
+          cell_type: 'code',
+          metadata: {},
+          source: ['def train():\n', '    pass\n'],
+          outputs: [],
+        },
+      ],
+    });
+    const result = extractNotebookPython(content);
+    expect(result).not.toBeNull();
+    expect(result!.pythonSource).toContain('def train():');
+    expect(result!.segments).toHaveLength(1);
+  });
+
+  it('keeps two code cells in order with two segments', () => {
+    const content = notebook({
+      language: 'python',
+      cells: [
+        { cell_type: 'code', metadata: {}, source: ['x = 1\n'], outputs: [] },
+        { cell_type: 'code', metadata: {}, source: ['def train():\n', '    return x\n'], outputs: [] },
+      ],
+    });
+    const result = extractNotebookPython(content);
+    expect(result).not.toBeNull();
+    expect(result!.pythonSource).toMatch(/x = 1\n+def train/);
+    expect(result!.segments).toHaveLength(2);
+    expect(result!.segments[1].extractStartLine).toBeGreaterThan(result!.segments[0].extractStartLine);
+    expect(result!.segments[1].jsonStartLine).toBeGreaterThan(result!.segments[0].jsonStartLine);
+  });
+
+  it('accepts source as a single string', () => {
+    const content = notebook({
+      language: 'python',
+      cells: [{ cell_type: 'code', metadata: {}, source: 'y = 2\n', outputs: [] }],
+    });
+    expect(extractNotebookPython(content)?.pythonSource).toContain('y = 2');
+  });
+
+  it('returns null for markdown-only notebooks', () => {
+    const content = notebook({
+      language: 'python',
+      cells: [{ cell_type: 'markdown', metadata: {}, source: ['# hi\n'] }],
+    });
+    expect(extractNotebookPython(content)).toBeNull();
+  });
+
+  it('returns null for invalid JSON', () => {
+    expect(extractNotebookPython('{not json')).toBeNull();
+  });
+
+  it('returns null for a Julia kernelspec', () => {
+    const content = notebook({
+      language: 'julia',
+      cells: [{ cell_type: 'code', metadata: {}, source: ['1 + 1\n'], outputs: [] }],
+    });
+    expect(extractNotebookPython(content)).toBeNull();
+  });
+
+  it('extracts python3 kernelspec', () => {
+    const content = notebook({
+      language: 'python3',
+      cells: [{ cell_type: 'code', metadata: {}, source: ['a = 1\n'], outputs: [] }],
+    });
+    expect(extractNotebookPython(content)?.pythonSource).toContain('a = 1');
+  });
+
+  it('comments line magics in place', () => {
+    const content = notebook({
+      language: 'python',
+      cells: [
+        {
+          cell_type: 'code',
+          metadata: {},
+          source: ['%time\n', 'x = 1\n', '!ls\n'],
+          outputs: [],
+        },
+      ],
+    });
+    const result = extractNotebookPython(content);
+    expect(result!.pythonSource.split('\n').filter((l) => l.length > 0)).toEqual([
+      '# %time',
+      'x = 1',
+      '# !ls',
+    ]);
+  });
+
+  it('skips a %%bash cell and still extracts later train', () => {
+    const content = notebook({
+      language: 'python',
+      cells: [
+        { cell_type: 'code', metadata: {}, source: ['%%bash\n', 'echo hi\n'], outputs: [] },
+        { cell_type: 'code', metadata: {}, source: ['def train():\n', '    pass\n'], outputs: [] },
+      ],
+    });
+    const result = extractNotebookPython(content);
+    expect(result!.pythonSource).toContain('def train');
+    expect(result!.pythonSource).not.toContain('echo hi');
+  });
+
+  it('maps identical duplicate cells to later JSON lines', () => {
+    const src = ['print(1)\n'];
+    const content = notebook({
+      language: 'python',
+      cells: [
+        { cell_type: 'code', metadata: {}, source: src, outputs: [] },
+        { cell_type: 'code', metadata: {}, source: src, outputs: [] },
+      ],
+    });
+    const result = extractNotebookPython(content);
+    expect(result!.segments).toHaveLength(2);
+    expect(result!.segments[1].jsonStartLine).toBeGreaterThan(result!.segments[0].jsonStartLine);
+  });
+
+  it('skips an R-language code cell and keeps Python cells', () => {
+    const content = notebook({
+      language: 'python',
+      cells: [
+        {
+          cell_type: 'code',
+          metadata: { language: 'R' },
+          source: ['x <- 1\n'],
+          outputs: [],
+        },
+        { cell_type: 'code', metadata: {}, source: ['z = 3\n'], outputs: [] },
+      ],
+    });
+    const result = extractNotebookPython(content);
+    expect(result!.pythonSource).toContain('z = 3');
+    expect(result!.pythonSource).not.toContain('x <- 1');
+  });
+});
+
+describe('mapExtractLine', () => {
+  it('maps a second-cell extract row onto that cell JSON line', () => {
+    const content = notebook({
+      language: 'python',
+      cells: [
+        { cell_type: 'markdown', metadata: {}, source: ['# intro\n'] },
+        { cell_type: 'code', metadata: {}, source: ['a = 1\n'], outputs: [] },
+        { cell_type: 'code', metadata: {}, source: ['def train():\n', '    pass\n'], outputs: [] },
+      ],
+    });
+    const extracted = extractNotebookPython(content)!;
+    const trainSeg = extracted.segments[1];
+    const mapped = mapExtractLine(trainSeg.extractStartLine, extracted.segments);
+    expect(mapped).toBe(trainSeg.jsonStartLine);
+    expect(mapped).toBeGreaterThan(extracted.segments[0].jsonStartLine);
+  });
+});
+
+describe('notebookPythonSnippet', () => {
+  it('returns Python def train not JSON cell_type', () => {
+    const content = notebook({
+      language: 'python',
+      cells: [{ cell_type: 'code', metadata: {}, source: ['def train():\n', '    pass\n'], outputs: [] }],
+    });
+    const extracted = extractNotebookPython(content)!;
+    const snippet = notebookPythonSnippet(
+      content,
+      extracted.segments[0].jsonStartLine,
+      extracted.segments[0].jsonEndLine,
+    );
+    expect(snippet).toContain('def train');
+    expect(snippet).not.toContain('cell_type');
+  });
+});
diff --git a/gitnexus/test/unit/ipynb-python-captures.test.ts b/gitnexus/test/unit/ipynb-python-captures.test.ts
new file mode 100644
index 000000000..505674de7
--- /dev/null
+++ b/gitnexus/test/unit/ipynb-python-captures.test.ts
@@ -0,0 +1,46 @@
+import { describe, it, expect } from 'vitest';
+import { emitPythonScopeCaptures } from '../../src/core/ingestion/languages/python/captures.js';
+import { pythonProvider } from '../../src/core/ingestion/languages/python.js';
+import { extractParsedFile } from '../../src/core/ingestion/scope-extractor-bridge.js';
+import { getLanguageFromFilename, SupportedLanguages } from 'gitnexus-shared';
+import { getProviderForFile } from '../../src/core/ingestion/languages/index.js';
+
+const notebook = JSON.stringify(
+  {
+    nbformat: 4,
+    nbformat_minor: 5,
+    metadata: {
+      kernelspec: { language: 'python', name: 'python3', display_name: 'Python' },
+    },
+    cells: [
+      { cell_type: 'code', metadata: {}, source: ['def train():\n', '    pass\n'], outputs: [] },
+    ],
+  },
+  null,
+  2,
+);
+
+describe('Python notebook scope captures', () => {
+  it('detects .ipynb as Python', () => {
+    expect(getLanguageFromFilename('analysis.ipynb')).toBe(SupportedLanguages.Python);
+    expect(getProviderForFile('n.ipynb')?.id).toBe(SupportedLanguages.Python);
+  });
+
+  it('does not parse raw JSON as Python on the full-file path', () => {
+    const matches = emitPythonScopeCaptures(notebook, 'analysis.ipynb');
+    const names = matches.flatMap((m) => Object.keys(m));
+    expect(names.some((k) => k.includes('function'))).toBe(true);
+  });
+
+  it('returns no captures for invalid notebook JSON', () => {
+    expect(emitPythonScopeCaptures('{not json', 'broken.ipynb')).toEqual([]);
+  });
+
+  it('extractParsedFile yields a Function for train', () => {
+    const parsed = extractParsedFile(pythonProvider, notebook, 'analysis.ipynb');
+    expect(parsed).toBeDefined();
+    expect(parsed!.localDefs.some((d) => d.qualifiedName === 'train' || d.name === 'train')).toBe(
+      true,
+    );
+  });
+});