--- title: "#langchain articles | Hashnode" description: "Explore 894 articles tagged #langchain on Hashnode. Tutorials, guides, and how-tos from the community." url: "https://hashnode.com/tag/langchain" --- Tag # #langchain 894 posts · 147 followers [Jeet Mondal](https://hashnode.com/@JeetMondal) · [4h ago](https://hashnode.com/posts/how-fast-can-you-build-an-ai-saas-mvp-in-2027/6af864f2ac40dc897e93280e) ### [How Fast Can You Build an AI SaaS MVP in 2027?](https://itsjeet.hashnode.dev/how-fast-can-you-build-an-ai-saas-mvp-in-2027?utm_source=hashnode&utm_medium=feed) A Benchmark Report 10 min read · [itsjeet.hashnode.dev](https://itsjeet.hashnode.dev/how-fast-can-you-build-an-ai-saas-mvp-in-2027?utm_source=hashnode&utm_medium=feed) [Kizuki](https://hashnode.com/@kizukidata) · [7h ago](https://hashnode.com/posts/timestamp-citations-from-youtube-transcripts-a-one-line-formula-and-where-it-stops-being-the-problem/6af838448b878446ec0823a1) ### [Timestamp citations from YouTube transcripts: a one-line formula, and where it stops being the problem](https://kizukidata.hashnode.dev/timestamp-citations-from-youtube-transcripts-a-one-line-formula-and-where-it-stops-being-the-problem?utm_source=hashnode&utm_medium=feed) 14 videos, 1,257 probes and 322 rewritten questions: LangChain's default chunks give a playable link about 25% of the time, and with rewritten questions most misses happen before the timestamp. 12 min read · [kizukidata.hashnode.dev](https://kizukidata.hashnode.dev/timestamp-citations-from-youtube-transcripts-a-one-line-formula-and-where-it-stops-being-the-problem?utm_source=hashnode&utm_medium=feed) [Waqas Shahid](https://hashnode.com/@practicaldevblog) · [11h ago](https://hashnode.com/posts/langchain-tutorial-build-your-first-llm-app-in-python/6af80d147dc9fd410bf6d1e4) ### [LangChain Tutorial: Build Your First LLM App in Python](https://practicaldevblog.hashnode.dev/langchain-tutorial-build-your-first-llm-app-in-python?utm_source=hashnode&utm_medium=feed) Quick answer LangChain is a Python framework for building applications powered by large language models, and in current LangChain 1.x you compose those applications with LCEL, the LangChain Expression 8 min read · [practicaldevblog.hashnode.dev](https://practicaldevblog.hashnode.dev/langchain-tutorial-build-your-first-llm-app-in-python?utm_source=hashnode&utm_medium=feed) [Noah Grinstein](https://hashnode.com/@noahcontrolplane) · [3d ago](https://hashnode.com/posts/self-host-langflow-on-control-plane-a-shared-agent-builder-with-postgresql-and-login-required/6af45ead494653f71d4c7812) ### [Self-Host Langflow on Control Plane: A Shared Agent Builder with PostgreSQL and Login Required](https://controlplane-eng.hashnode.dev/self-host-langflow-on-control-plane-a-shared-agent-builder-with-postgresql-and-login-required?utm_source=hashnode&utm_medium=feed) Self-host Langflow on Control Plane as a shared agent builder backed by PostgreSQL, with login required for your team. 9 min read · [controlplane-eng.hashnode.dev](https://controlplane-eng.hashnode.dev/self-host-langflow-on-control-plane-a-shared-agent-builder-with-postgresql-and-login-required?utm_source=hashnode&utm_medium=feed) [Noah Grinstein](https://hashnode.com/@noahcontrolplane) · [3d ago](https://hashnode.com/posts/self-host-langgraph-agents-with-aegra-on-control-plane-a-private-agent-server/6af42667bb5e7767f89db93b) ### [Self-Host LangGraph Agents with Aegra on Control Plane: A Private Agent Server](https://controlplane-eng.hashnode.dev/self-host-langgraph-agents-with-aegra-on-control-plane-a-private-agent-server?utm_source=hashnode&utm_medium=feed) Self-host LangGraph agents with Aegra on Control Plane: install the template, connect Postgres, and stream runs from a private agent server. 9 min read · [controlplane-eng.hashnode.dev](https://controlplane-eng.hashnode.dev/self-host-langgraph-agents-with-aegra-on-control-plane-a-private-agent-server?utm_source=hashnode&utm_medium=feed) [MemorySync](https://hashnode.com/@memorysync) · [5d ago](https://hashnode.com/posts/langgraph-checkpointer-requires-configurable-keys-thread-id/6af1f32d05abf4c5d7b4c213) ### [LangGraph: fixing 'Checkpointer requires one or more of the following configurable keys: thread\_id, checkpoint\_ns, checkpoint\_id'](https://memorysync.hashnode.dev/langgraph-checkpointer-requires-configurable-keys-thread-id?utm_source=hashnode&utm_medium=feed) A graph compiled with a checkpointer needs a thread\_id in config\['configurable'\] on every call. Here's where it goes, why context= doesn't count, why LangServe drops it, and why None or an empty string is worse than the error. 13 min read · [memorysync.hashnode.dev](https://memorysync.hashnode.dev/langgraph-checkpointer-requires-configurable-keys-thread-id?utm_source=hashnode&utm_medium=feed) [Belal Shafiq](https://hashnode.com/@bshafiq) · [5d ago](https://hashnode.com/posts/how-a-silent-agent-loop-cost-me-3k-in-api-bills-and-how-i-fixed-it/6af1cbbab9a850fdf0de576f) ### [How a Silent Agent Loop Cost Me $3k in API Bills (And How I Fixed It)](https://agenttrafficcop.hashnode.dev/how-a-silent-agent-loop-cost-me-3k-in-api-bills-and-how-i-fixed-it?utm_source=hashnode&utm_medium=feed) Stop silent agent loops from draining your API budget. Learn how a multi-agent ping-pong loop cost me $3k and how to fix it with runtime middleware. 4 min read · [agenttrafficcop.hashnode.dev](https://agenttrafficcop.hashnode.dev/how-a-silent-agent-loop-cost-me-3k-in-api-bills-and-how-i-fixed-it?utm_source=hashnode&utm_medium=feed) [2](https://hashnode.com/posts/how-a-silent-agent-loop-cost-me-3k-in-api-bills-and-how-i-fixed-it/6af1cbbab9a850fdf0de576f) [MemorySync](https://hashnode.com/@memorysync) · [6d ago](https://hashnode.com/posts/langgraph-could-not-reconstruct-builtins-set-from-checkpoint/6af09f6798fe0effe84c79dd) ### [LangGraph 'Could not reconstruct builtins.set from checkpoint': why a set of tuples comes back as a list](https://memorysync.hashnode.dev/langgraph-could-not-reconstruct-builtins-set-from-checkpoint?utm_source=hashnode&utm_medium=feed) A set of tuples in LangGraph state comes back from a checkpoint as a list of lists (or None on langgraph-checkpoint 4.2.0). Why the serializer can't rebuild it, and a state shape that round-trips, tested on langgraph 1.2.20. 13 min read · [memorysync.hashnode.dev](https://memorysync.hashnode.dev/langgraph-could-not-reconstruct-builtins-set-from-checkpoint?utm_source=hashnode&utm_medium=feed) [Sai Kiran Kshatriya](https://hashnode.com/@saikirankshatriya) · [Nov 5](https://hashnode.com/posts/run-a-langchain-deep-agent-on-a-cockroachdb-virtual-cluster-with-durable-checkpoints/6aece924f0cf0d9b23124a43) ### [Run a LangChain Deep Agent on a CockroachDB Virtual Cluster with Durable Checkpoints](https://saikirankshatriya.hashnode.dev/run-a-langchain-deep-agent-on-a-cockroachdb-virtual-cluster-with-durable-checkpoints?utm_source=hashnode&utm_medium=feed) A stateful agent that survives a restart, a human-approval pause, and a lost process — because its checkpointer lives in an isolated virtual cluster. 18 min read · [saikirankshatriya.hashnode.dev](https://saikirankshatriya.hashnode.dev/run-a-langchain-deep-agent-on-a-cockroachdb-virtual-cluster-with-durable-checkpoints?utm_source=hashnode&utm_medium=feed) [AgentSearch](https://hashnode.com/@agentsearchhq) · [Nov 5](https://hashnode.com/posts/add-web-search-to-langgraph-agent/6aec9f280174d07cd559e959) ### [How to Add Web Search to a LangGraph Agent in Python (No API Key)](https://agentsearchhq.hashnode.dev/add-web-search-to-langgraph-agent?utm_source=hashnode&utm_medium=feed) Add live web search to a LangGraph agent with langchain-agentsearch: StateGraph, ToolNode, memory, streaming and spend caps. Free, no API key. 10 min read · [agentsearchhq.hashnode.dev](https://agentsearchhq.hashnode.dev/add-web-search-to-langgraph-agent?utm_source=hashnode&utm_medium=feed)