https://invasikode.com Tech publication: programming tutorials, AI exploration, and software architecture guides. en Sat, 21 Nov 2026 01:00:00 +0000 Invasikode https://invasikode.com/p/tentang-struktur-data-linked-list https://invasikode.com/p/tentang-struktur-data-linked-list Sat, 21 Nov 2026 01:00:00 +0000 A linked list is a linear chain of nodes, each holding data and a pointer to the next node. Here is what that chain looks like, what it costs next to an array, and the same minimal implementation in Java, Python, and JavaScript. Daffa Izzuddin struktur-data linked-list pointer konsep https://invasikode.com/p/pentingnya-memahami-algoritma-dan-struktur-data https://invasikode.com/p/pentingnya-memahami-algoritma-dan-struktur-data Thu, 19 Nov 2026 01:00:00 +0000 An algorithm is an ordered list of steps, and that order decides how expensive a problem is. The examples are on the back of an instant noodle packet, in a factorial, and behind ctrl+z. Daffa Izzuddin algoritma struktur-data konsep dasar https://invasikode.com/p/jam-11-kuota-ai-habis-kerjaan-berhenti https://invasikode.com/p/jam-11-kuota-ai-habis-kerjaan-berhenti Thu, 12 Nov 2026 01:00:00 +0000 The panel says the usage limit is reached and the work stops, not because it is finished. Three guesses explain it, and all three are wrong: the limit is shaped like a cliff, and the day is built on top of one tool. Daffa Izzuddin ai tooling rate-limit produktivitas https://invasikode.com/p/cache-hit-rate-zero https://invasikode.com/p/cache-hit-rate-zero Sun, 08 Nov 2026 01:20:00 +0000 Twenty-four turns, caching switched on, and a bill 21% higher than running with no cache at all. A support agent whose prompt looks static, and the three lines that quietly change it every turn. Daffa Izzuddin lab llm cache api https://invasikode.com/p/what-a-prompt-cache-remembers https://invasikode.com/p/what-a-prompt-cache-remembers Sun, 08 Nov 2026 01:10:00 +0000 Four providers cache the same bytes under four different rulebooks. The question that decides your bill: when the second request is longer than the first, does it reuse the whole prefix or only the part that was already written? Daffa Izzuddin llm ai-agent cache api https://invasikode.com/p/python-venv-pip https://invasikode.com/p/python-venv-pip Sat, 07 Nov 2026 12:00:00 +0000 pip install printed Successfully installed, and the next run raised ModuleNotFoundError on the same machine. Two interpreters, one install, and the variable your script checks is the one the interpreter never sets. Daffa Izzuddin python venv pip https://invasikode.com/p/python-class-object https://invasikode.com/p/python-class-object Sat, 07 Nov 2026 01:00:00 +0000 Two accounts, and each history lists the other account's deposits. The list sat in the class body, append never writes to the object, so both accounts appended into the same one. Daffa Izzuddin python oop https://invasikode.com/p/java-operators https://invasikode.com/p/java-operators Fri, 06 Nov 2026 01:00:00 +0000 Three scores, one division, and the average prints as 82. Both operands are int, so the fraction is cut off, and the obvious cast prints 82.0 without fixing anything. Daffa Izzuddin java operator https://invasikode.com/p/python-modules https://invasikode.com/p/python-modules Fri, 06 Nov 2026 01:00:00 +0000 You pull one function out into its own file, import it, and the whole report runs again and eats your input. A module is a file, import runs it top to bottom, and one line decides which of the two jobs it is doing. Daffa Izzuddin python modules https://invasikode.com/p/caching-that-never-hits https://invasikode.com/p/caching-that-never-hits Wed, 04 Nov 2026 01:10:00 +0000 Same model, same conversation, same token count, and a bill five times higher. The cause is a prefix that changes, a write premium nobody reads about, and a cost curve that grows faster than the loop. Daffa Izzuddin llm ai-agent cache api https://invasikode.com/p/your-stream-dies-at-125-seconds https://invasikode.com/p/your-stream-dies-at-125-seconds Wed, 04 Nov 2026 01:00:00 +0000 Streaming moves the wait into a connection that outlives the request. Four layers sit between the model and the browser, their idle timeouts disagree, and the smallest one ends your stream. Daffa Izzuddin streaming sse ai-agent api https://invasikode.com/p/python-strings https://invasikode.com/p/python-strings Wed, 28 Oct 2026 13:00:00 +0000 The badge script printed the right name for the person who wrote it and the wrong name for everybody else. Slicing counts characters, and a name is words. Daffa Izzuddin python string https://invasikode.com/p/python-tuples https://invasikode.com/p/python-tuples Wed, 28 Oct 2026 12:00:00 +0000 Three points walk into a loop and come out identical. The list was never copied three times; the name was. A tuple makes that bug impossible. Daffa Izzuddin python tuple https://invasikode.com/p/python-sets https://invasikode.com/p/python-sets Wed, 28 Oct 2026 11:00:00 +0000 A de-duplication loop that works on clean data leaves four tags where there should be two. The bug is case, and the fix is a set. Daffa Izzuddin python set https://invasikode.com/p/python-dictionary https://invasikode.com/p/python-dictionary Wed, 28 Oct 2026 10:00:00 +0000 A word counter dies the first time it meets a word twice. The fix is one line; what takes longer is knowing which of a dict's three lookups to reach for. Daffa Izzuddin python dictionary https://invasikode.com/p/rag-pisah-jalur-query-dan-ingestion https://invasikode.com/p/rag-pisah-jalur-query-dan-ingestion Thu, 22 Oct 2026 01:30:00 +0000 One RAG service that both parses uploads and answers queries will fall over the moment someone uploads a 200-page PDF. The cure is two paths and one queue. Daffa Izzuddin rag cloud-run cloud-tasks gcp serverless arsitektur https://invasikode.com/p/multi-agen-linear-atau-grafik https://invasikode.com/p/multi-agen-linear-atau-grafik Wed, 21 Oct 2026 16:05:00 +0000 One agent with twenty tools gets messy fast. Once several agents revise each other, you need a graph that allows cycles and a number that makes it stop. Daffa Izzuddin multi-agent langgraph autogen orkestrasi checkpoint llm https://invasikode.com/p/kenapa-rag-cuma-cosine-similarity-sering-nyasar https://invasikode.com/p/kenapa-rag-cuma-cosine-similarity-sering-nyasar Mon, 19 Oct 2026 02:04:06 +0000 RAG that leans only on embeddings returns chunks that look close in meaning, not the ones you need. Here is why, and the two layers that patch it. Daffa Izzuddin rag vector-search bm25 hybrid-search retrieval embedding https://invasikode.com/p/memori-ai-agent-vector-store-ke-temporal-graph https://invasikode.com/p/memori-ai-agent-vector-store-ke-temporal-graph Sun, 18 Oct 2026 13:13:29 +0000 Two contradictory facts make an agent answer nonsense. Here is how a vector store and a temporal knowledge graph differ at keeping long-term state. Daffa Izzuddin ai llm backend system-design https://invasikode.com/p/mcp-dibongkar-ulang-kabar-baik-buat-kamu https://invasikode.com/p/mcp-dibongkar-ulang-kabar-baik-buat-kamu Fri, 16 Oct 2026 05:00:00 +0000 You have a few internal APIs and one AI agent, but the code has to be rewritten every time the model changes. MCP ends that, and this year the protocol was rebuilt so servers can run like ordinary web servers. Here's what changed. 🔧 Invasikode mcp model-context-protocol ai-agent llm backend python