React Flow Architect

Incremental Node Building

const buildVisibleNodes = useCallback(
  (allNodes: TreeNode[], expandedIds: Set<string>, otherDeps: any[]) => {
    const visibleNodes = new Map<string, TreeNode>();
    const visibleEdges = new Map<string, TreeEdge>();

    // Start with root nodes
    const rootNodes = allNodes.filter((n) => n.data.level === 0);

    // Recursively add visible nodes
    const addVisibleChildren = (node: TreeNode) => {
      visibleNodes.set(node.id, node);

      if (expandedIds.has(node.id)) {
        const children = allNodes.filter((n) => n.parentNode === node.id);
        children.forEach((child) => addVisibleChildren(child));
      }
    };

    rootNodes.forEach((root) => addVisibleChildren(root));

    return {
      nodes: Array.from(visibleNodes.values()),
      edges: Array.from(visibleEdges.values()),
    };
  },
  [],
);

Performance Optimization

Handle large datasets with incremental rendering and memoization.

Incremental Rendering

const useIncrementalGraph = (
  allNodes: Node[],
  allEdges: Edge[],
  expandedList: string[],
) => {
  const prevExpandedListRef = useRef<Set<string>>(new Set());
  const prevOtherDepsRef = useRef<any[]>([]);

  const { visibleNodes, visibleEdges } = useMemo(() => {
    const currentExpandedSet = new Set(expandedList);
    const prevExpandedSet = prevExpandedListRef.current;

    // Check if expanded list changed
    const expandedChanged = !areSetsEqual(currentExpandedSet, prevExpandedSet);

    // Check if other dependencies changed
    const otherDepsChanged = !arraysEqual(otherDeps, prevOtherDepsRef.current);

    if (expandedChanged && !otherDepsChanged) {
      // Only expanded list changed - incremental update
      return buildIncrementalUpdate(
        cachedVisibleNodesRef.current,
        cachedVisibleEdgesRef.current,
        allNodes,
        allEdges,
        currentExpandedSet,
        prevExpandedSet,
      );
    } else {
      // Full rebuild needed
      return buildFullGraph(allNodes, allEdges, currentExpandedSet);
    }
  }, [allNodes, allEdges, expandedList, ...otherDeps]);

  return { visibleNodes, visibleEdges };
};

Memoization Patterns

// Memoize node components to prevent unnecessary re-renders
const ProcessNode = memo(({ data, selected }: NodeProps) => {
  return (
    <div className={`process-node ${selected ? 'selected' : ''}`}>
      {data.label}
    </div>
  );
}, (prevProps, nextProps) => {
  // Custom comparison function
  return (
    prevProps.data.label === nextProps.data.label &&
    prevProps.selected === nextProps.selected &&
    prevProps.data.isExpanded === nextProps.data.isExpanded
  );
});

// Memoize edge calculations
const styledEdges = useMemo(() => {
  return edges.map(edge => ({
    ...edge,
    style: {
      ...edge.style,
      strokeWidth: selectedEdgeId === edge.id ? 3 : 2,
      stroke: selectedEdgeId === edge.id ? '#3b82f6' : '#94a3b8',
    },
    animated: selectedEdgeId === edge.id,
  }));
}, [edges, selectedEdgeId]);

State Management

Complex node/edge state patterns with undo/redo and persistence.

Reducer Pattern

type GraphAction =
  | { type: "SELECT_NODE"; payload: string }
  | { type: "SELECT_EDGE"; payload: string }
  | { type: "TOGGLE_EXPAND"; payload: string }
  | { type: "UPDATE_NODES"; payload: Node[] }
  | { type: "UPDATE_EDGES"; payload: Edge[] }
  | { type: "UNDO" }
  | { type: "REDO" };

const graphReducer = (state: GraphState, action: GraphAction): GraphState => {
  switch (action.type) {
    case "SELECT_NODE":
      return {
        ...state,
        selectedNodeId: action.payload,
        selectedEdgeId: null,
      };

    case "TOGGLE_EXPAND":
      const newExpanded = new Set(state.expandedNodeIds);
      if (newExpanded.has(action.payload)) {
        newExpanded.delete(action.payload);
      } else {
        newExpanded.add(action.payload);
      }
      return {
        ...state,
        expandedNodeIds: newExpanded,
        isDirty: true,
      };

    default:
      return state;
  }
};

History Management

const useHistoryManager = (
  state: GraphState,
  dispatch: Dispatch<GraphAction>,
) => {
  const canUndo = state.historyIndex > 0;
  const canRedo = state.historyIndex < state.history.length - 1;

  const undo = useCallback(() => {
    if (canUndo) {
      const newIndex = state.historyIndex - 1;
      const historyEntry = state.history[newIndex];

      dispatch({
        type: "RESTORE_FROM_HISTORY",
        payload: {
          ...historyEntry,
          historyIndex: newIndex,
        },
      });
    }
  }, [canUndo, state.historyIndex, state.history]);

  const saveToHistory = useCallback(() => {
    dispatch({ type: "SAVE_TO_HISTORY" });
  }, [dispatch]);

  return { canUndo, canRedo, undo, redo, saveToHistory };
};

Advanced Features

Auto-Layout Integration

Integrate Dagre for automatic graph layout:

import dagre from "dagre";

const layoutOptions = {
  rankdir: "TB", // Top to Bottom
  nodesep: 100, // Node separation
  ranksep: 150, // Rank separation
  marginx: 50,
  marginy: 50,
  edgesep: 10,
};

const applyLayout = (nodes: Node[], edges: Edge[]) => {
  const g = new dagre.graphlib.Graph();
  g.setGraph(layoutOptions);
  g.setDefaultEdgeLabel(() => ({}));

  // Add nodes to graph
  nodes.forEach((node) => {
    g.setNode(node.id, { width: 200, height: 100 });
  });

  // Add edges to graph
  edges.forEach((edge) => {
    g.setEdge(edge.source, edge.target);
  });

  // Calculate layout
  dagre.layout(g);

  // Apply positions
  return nodes.map((node) => ({
    ...node,
    position: {
      x: g.node(node.id).x - 100,
      y: g.node(node.id).y - 50,
    },
  }));
};

// Debounce layout calculations
const debouncedLayout = useMemo(() => debounce(applyLayout, 150), []);

Focus Mode

Isolate selected nodes and their direct connections:

const useFocusMode = (
  selectedNodeId: string,
  allNodes: Node[],
  allEdges: Edge[],
) => {
  return useMemo(() => {
    if (!selectedNodeId) return { nodes: allNodes, edges: allEdges };

    // Get direct connections
    const connectedNodeIds = new Set([selectedNodeId]);
    const focusedEdges: Edge[] = [];

    allEdges.forEach((edge) => {
      if (edge.source === selectedNodeId || edge.target === selectedNodeId) {
        focusedEdges.push(edge);
        connectedNodeIds.add(edge.source);
        connectedNodeIds.add(edge.target);
      }
    });

    // Get connected nodes
    const focusedNodes = allNodes.filter((n) => connectedNodeIds.has(n.id));

    return { nodes: focusedNodes, edges: focusedEdges };
  }, [selectedNodeId, allNodes, allEdges]);
};

// Smooth transitions for focus mode
const focusModeStyles = {
  transition: "all 0.3s ease-in-out",
  opacity: isInFocus ? 1 : 0.3,
  filter: isInFocus ? "none" : "blur(2px)",
};

Search Integration

Search and navigate to specific nodes:

const searchNodes = useCallback((nodes: Node[], query: string) => {
  if (!query.trim()) return [];

  const lowerQuery = query.toLowerCase();
  return nodes.filter(
    (node) =>
      node.data.label.toLowerCase().includes(lowerQuery) ||
      node.data.description?.toLowerCase().includes(lowerQuery),
  );
}, []);

const navigateToSearchResult = (nodeId: string) => {
  // Expand parent nodes
  const nodePath = calculateBreadcrumbPath(nodeId, allNodes);
  const parentIds = nodePath.slice(0, -1).map((n) => n.id);

  setExpandedIds((prev) => new Set([...prev, ...parentIds]));
  setSelectedNodeId(nodeId);

  // Fit view to node
  fitView({ nodes: [{ id: nodeId }], duration: 800 });
};

Performance Tools

Graph Performance Analyzer

Create a performance analysis script:

// scripts/graph-analyzer.js
class GraphAnalyzer {
  analyzeCode(content, filePath) {
    const analysis = {
      metrics: {
        nodeCount: this.countNodes(content),
        edgeCount: this.countEdges(content),
        renderTime: this.estimateRenderTime(content),
        memoryUsage: this.estimateMemoryUsage(content),
        complexity: this.calculateComplexity(content),
      },
      issues: [],
      optimizations: [],
      patterns: this.detectPatterns(content),
    };

    // Detect performance issues
    this.detectPerformanceIssues(analysis);

    // Suggest optimizations
    this.suggestOptimizations(analysis);

    return analysis;
  }

  countNodes(content) {
    const nodePatterns = [
      /nodes:\s*\[.*?\]/gs,
      /const\s+\w+\s*=\s*\[.*?id:.*?position:/gs,
    ];

    let totalCount = 0;
    nodePatterns.forEach((pattern) => {
      const matches = content.match(pattern);
      if (matches) {
        matches.forEach((match) => {
          const nodeMatches = match.match(/id:\s*['"`][^'"`]+['"`]/g);
          if (nodeMatches) {
            totalCount += nodeMatches.length;
          }
        });
      }
    });

    return totalCount;
  }

  estimateRenderTime(content) {
    const nodeCount = this.countNodes(content);
    const edgeCount = this.countEdges(content);

    // Base render time estimation (ms)
    const baseTime = 5;
    const nodeTime = nodeCount * 0.1;
    const edgeTime = edgeCount * 0.05;

    return baseTime + nodeTime + edgeTime;
  }

  detectPerformanceIssues(analysis) {
    const { metrics } = analysis;

    if (metrics.nodeCount > 500) {
      analysis.issues.push({
        type: "HIGH_NODE_COUNT",
        severity: "high",
        message: `Too many nodes (${metrics.nodeCount}). Consider virtualization.`,
        suggestion: "Implement virtualization or reduce visible nodes",
      });
    }

    if (metrics.renderTime > 16) {
      analysis.issues.push({
        type: "SLOW_RENDER",
        severity: "high",
        message: `Render time (${metrics.renderTime.toFixed(2)}ms) exceeds 60fps.`,
        suggestion: "Optimize with memoization and incremental rendering",
      });
    }
  }
}

Best Practices

Performance Guidelines

1. Use React.memo for node components to prevent unnecessary re-renders
2. Implement virtualization for graphs with 1000+ nodes
3. Debounce layout calculations during rapid interactions
4. Use useCallback for edge creation and manipulation functions
5. Implement proper TypeScript types for nodes and edges

Memory Management

// Use Map for O(1) lookups instead of array.find
const nodesById = useMemo(
  () => new Map(allNodes.map((n) => [n.id, n])),
  [allNodes],
);

// Cache layout results
const layoutCacheRef = useRef<Map<string, Node[]>>(new Map());

// Proper cleanup in useEffect
useEffect(() => {
  return () => {
    // Clean up any lingering references
    nodesMapRef.current.clear();
    edgesMapRef.current.clear();
  };
}, []);

State Optimization

// Use useRef for objects that shouldn't trigger re-renders
const autoSaveDataRef = useRef({
  nodes: [],
  edges: [],
  lastSaved: Date.now(),
});

// Update properties without breaking reference
const updateAutoSaveData = (newNodes: Node[], newEdges: Edge[]) => {
  autoSaveDataRef.current.nodes = newNodes;
  autoSaveDataRef.current.edges = newEdges;
  autoSaveDataRef.current.lastSaved = Date.now();
};

Common Problems & Solutions

Performance Issues

• Problem: Lag during node expansion

• Solution: Implement incremental rendering with change detection

• Problem: Memory usage increases over time

• Solution: Proper cleanup in useEffect hooks and use WeakMap for temporary data

Layout Conflicts

• Problem: Manual positioning conflicts with auto-layout
• Solution: Use controlled positioning state and separate layout modes

Rendering Issues

• Problem: Excessive re-renders

• Solution: Use memo, useMemo, and useCallback with stable dependencies

• Problem: Slow layout calculations

• Solution: Debounce layout calculations and cache results

Complete Example

import React, { useState, useCallback, useMemo, useRef } from 'react';
import ReactFlow, { Node, Edge, useReactFlow } from 'reactflow';
import dagre from 'dagre';
import { debounce } from 'lodash';

interface GraphState {
  nodes: Node[];
  edges: Edge[];
  selectedNodeId: string | null;
  expandedNodeIds: Set<string>;
  history: GraphState[];
  historyIndex: number;
}

export default function InteractiveGraph() {
  const [state, setState] = useState<GraphState>({
    nodes: [],
    edges: [],
    selectedNodeId: null,
    expandedNodeIds: new Set(),
    history: [],
    historyIndex: 0,
  });

  const { fitView } = useReactFlow();
  const layoutCacheRef = useRef<Map<string, Node[]>>(new Map());

  // Memoized styled edges
  const styledEdges = useMemo(() => {
    return state.edges.map(edge => ({
      ...edge,
      style: {
        ...edge.style,
        strokeWidth: state.selectedNodeId === edge.source || state.selectedNodeId === edge.target ? 3 : 2,
        stroke: state.selectedNodeId === edge.source || state.selectedNodeId === edge.target ? '#3b82f6' : '#94a3b8',
      },
      animated: state.selectedNodeId === edge.source || state.selectedNodeId === edge.target,
    }));
  }, [state.edges, state.selectedNodeId]);

  // Debounced layout calculation
  const debouncedLayout = useMemo(
    () => debounce((nodes: Node[], edges: Edge[]) => {
      const cacheKey = generateLayoutCacheKey(nodes, edges);

      if (layoutCacheRef.current.has(cacheKey)) {
        return layoutCacheRef.current.get(cacheKey)!;
      }

      const layouted = applyDagreLayout(nodes, edges);
      layoutCacheRef.current.set(cacheKey, layouted);

      return layouted;
    }, 150),
    []
  );

  const handleNodeClick = useCallback((event: React.MouseEvent, node: Node) => {
    setState(prev => ({
      ...prev,
      selectedNodeId: node.id,
    }));
  }, []);

  const handleToggleExpand = useCallback((nodeId: string) => {
    setState(prev => {
      const newExpanded = new Set(prev.expandedNodeIds);
      if (newExpanded.has(nodeId)) {
        newExpanded.delete(nodeId);
      } else {
        newExpanded.add(nodeId);
      }

      return {
        ...prev,
        expandedNodeIds: newExpanded,
      };
    });
  }, []);

  return (
    <ReactFlow
      nodes={state.nodes}
      edges={styledEdges}
      onNodeClick={handleNodeClick}
      fitView
    />
  );
}

This comprehensive skill provides everything needed to build production-ready ReactFlow applications with hierarchical navigation, performance optimization, and advanced state management patterns.

When to Use

This skill is applicable to execute the workflow or actions described in the overview.

Limitations

• Use this skill only when the task clearly matches the scope described above.
• Do not treat the output as a substitute for environment-specific validation, testing, or expert review.
• Stop and ask for clarification if required inputs, permissions, safety boundaries, or success criteria are missing.