Visualize the Source code
Master complex codebases within minutes. Callgraph.io generates interactive execution flows using dynamic tracing for high performance system softwares like databases, caches and web servers, giving you an intuitive grasp of how the project works - instantly.

Features
Stop reading code. Start viewing it.
Interactive Function Call Tree
View function calls as an interactive Tree. Expand and collapse nodes to focus on the logic that matters to you. The data being dynamically generated is more accurate.
AI Explanations
Click any function in the call graph for an instant AI-powered definition and a deep-dive code explanation.
Inverted Index
Select a function to reveal its callers. Seamlessly jump between every location where they are invoked.
Fork() tracing
Seamlessly navigate between parent and child process call stacks during fork events.
Dynamic Analysis
Callgraph uses Dynamic analysis instead of static which gives highly accurate results.
Private Projects
Securely onboard and analyze your personal or proprietary projects.
Callgraph in Action
Callgraph lets you navigate and understand complex execution flows.
Supported Projects
Master database internals and system programming with our vast library of mapped projects

Valkey
ValKey is the linux foundation backed fork of Redis meant to be truly open source.

Redis
Redis is an open source in-memory data structure store, used as a database, cache, and message broker. Majority of the Redis flows are similar to that of Valkey.

Nginx
Nginx is a high performance web server, reverse proxy and load balancer.

PostgreSQL
Most advanced and widely used open source relational database management system

SQLite
Embedded Database. The world's most deployed database engine; it’s serverless, zero-config, and lives entirely within a single file on your disk.

Mysql
The most popular open-source relational database globally.

RocksDB
Embedded library that provides a persistent key-value store for fast storage.

Memcached
Memcached is a high performance in memory key value store

LMDB
Lightening memory DB is an ultra-fast, tiny, B+ tree-based database that maps data directly into memory for near-instant access.

WiredTiger
High performance and multithreaded Storage Engine for Mongodb

Aerospike server
Aerospike is a high performance NoSQL database optimized for SSDs. It scales to Petabytes of data.

Varnish-cache
An HTTP accerator and reverse proxy that sits in front of web servers to cache content and serve it at lightning speeds.
Jemalloc
Jemalloc is a specialized memory allocator (a replacement for malloc) designed to reduce fragmentation and improve concurrency in heavy applications
jq
JQ a lightweight tool used to slice, filter, and transform JSON data with ease.
ValkeyJson
ValkeyJson is a module for Valkey that allows you to store, query, and manipulate JSON documents natively within Valkey.

Unqlite
Embedded Nosql DB inspired from Sqlite. Focussed on JSON documents and key value pairs
redis-py
redis-py is a Python client for Redis
Onboard Your Project
Don't see your specific project? We support onboarding private projects too.
Get StartedAbout Callgraph.io
Callgraph.io was built for engineers ready to master systems programming and deep-dive into database internals. We know the friction of onboarding onto massive C/C++ codebases like Redis or PostgreSQL. Manual code tracing is a bottleneck; our tool parses source code to generate visual maps of execution threads, helping you build a complete mental model in minutes, not weeks.