Scaling Custom AI Application Development Through Modular LLM Framework

blackrock · Finance · year n/a · source Agentic: yes · promotional bias: med · source-backed · extracted with prompt 0.5.6 (schema v2)

Generated from extraction.json — do not edit by hand. Every claim cites verbatim source evidence; stated means the quote directly asserts the claim, implied means it supports it indirectly.

Problem

Domain: Internal AI application development for regulated investment operations

BlackRock needed to build many custom AI applications for investment operations much faster while keeping domain experts, compliance, and human review embedded in the workflow.

Constraints:

Architecture

BlackRock built a modular framework with a Sandbox and App Factory. The Sandbox lets investment-operations domain experts configure extraction templates, prompts, data types, validations, inter-field dependencies, transformation logic, and LLM strategy. The App Factory turns sandbox definitions into deployable apps with the right data/developer platform, cluster, access control, and distribution. Human-in-the-loop review remains central for compliance.

Diagram confidence: reconstructed (reconstructed from prose).

flowchart LR
  A["Document ingestion pipeline"] --> B["Sandbox"]
  B --> C["Extraction template manager"]
  B --> D["Domain expert workflow"]
  C --> E["Transformation executors"]
  D --> J["Human review gate"]
  B --> F["App Factory"]
  E --> F
  F --> G["Developer platform"]
  F --> H["Deployment cluster selector"]
  F --> I["Access control layer"]
  G --> K["Downstream applications"]
  I --> K
Drag to pan · scroll or use +/− to zoom · reconstructed from the source's described component topology

Components

Component Role Interacts with
Document ingestion pipeline Ingests prospectuses, term sheets, and other investment-operation documents. Sandbox
Sandbox Playground where domain experts configure templates, prompts, validations, LLM strategy, and extraction runs. Extraction template manager, Domain expert workflow, App Factory
Extraction template manager Configures fields, prompts, data types, validations, constraints, and inter-field dependencies. Sandbox, Transformation executors
Domain expert workflow Equity, ETF, operations, and business experts iterating on extraction and app requirements. Sandbox, Human review gate
Transformation executors Low-code transformation and workflow logic connecting extracted fields to downstream app requirements. App Factory
App Factory Cloud-native deployment operator that turns sandbox definitions into production applications. Developer platform, Deployment cluster selector, Access control layer
Developer platform Orchestration and app ecosystem used to deploy and distribute internal applications. Downstream applications
Deployment cluster selector Chooses GPU inference, burstable, or other compute based on application workload. App Factory
Access control layer Distribution and access control for regulated internal users. Downstream applications
Human review gate Four-eyes compliance and domain review before or during production use. Domain expert workflow
Downstream applications Reports, apps, and systems that consume transformed structured outputs. Developer platform

Data flow

Prospectuses or term sheets are ingested into pipelines, domain experts configure extraction templates in the Sandbox, extraction runs produce structured outputs, transformations/executors encode business logic, and the App Factory deploys the resulting application into BlackRock's app ecosystem with appropriate infrastructure and compliance controls.

3 supporting quotes
“ingest your prospectors or a term sheet. It pushes it through a particular pipeline”transcript, stated
“domain experts and these are like your business teams, your equity teams, ETF teams, etc.”transcript, stated
“all the things that operators do through this iteration cycle of through the sandbox. They take all that knowledge, the extraction templates”transcript, stated

Why this architecture

BlackRock moves prompt, extraction-template, and LLM-strategy iteration into the hands of domain experts, then uses an app factory to make deployment repeatable. This solves the speed problem without pretending regulated finance can remove human review.

3 supporting quotes
“if you can get that sandbox out into the hands of the domain experts then your iteration speed becomes really fast”transcript, stated
“human in the loop is super important”transcript, stated
“with compliance with regulations you kind of need those four eyes check”transcript, stated

Models used: LLMs for document extraction · LLMs for Q&A systems · LLMs for agentic systems · configurable model providers

Scale

Alternatives considered (roads not taken)

Fully agentic systems for the workflow

Rejected because: Financial-domain complexity and embedded human knowledge made full autonomy insufficient.

“We tried this with agentic systems doesn't quite work right now because of the complexity and the the domain knowledge that's imbued in the human head”transcript, stated

Engineering-led prompt and template iteration

Rejected because: Domain experts know the extraction and validation requirements, and moving iteration to them speeds delivery.

“prompt creation or extraction templates choosing an LLM strategy right having extraction runs”transcript, stated

One fixed deployment cluster for all AI apps

Rejected because: Different workloads need different compute, from GPU inference to burstable clusters.

“what type of cluster am I going to deploy this to?”transcript, stated

Patterns

human-in-the-loop-gate (governance)

BlackRock explicitly designs for domain-expert and four-eyes review in regulated financial workflows.

“design for human in the loop first uh if you're in a highly regulated environment”transcript, stated

structured-output-contract (interface)

Extraction templates define fields, data types, validations, constraints, and inter-field dependencies.

“multiple QC checks on the result values. I need to have a lot of validations and constraints on the fields”transcript, stated

tool-use-orchestration (agent-architecture)

The framework orchestrates document ingestion, extraction templates, transformations, app deployment, and downstream integrations.

“run through X number of steps and then integrate to my downstream systems”transcript, stated

model-routing (model-ops)

Domain experts choose LLM strategies and deployment clusters appropriate to the application.

“choosing an LLM strategy right having extraction runs”transcript, stated

Tradeoffs

Automation design

Chose human-in-the-loop framework over fully agentic processing.

Rationale: Regulated investment operations need compliance and domain checks.

“with compliance with regulations you kind of need those four eyes check”transcript, stated

Iteration ownership

Chose domain-expert sandbox over engineering-only app development.

Rationale: Domain experts can iterate faster on extraction fields, prompts, validations, and strategies.

“if you can get that sandbox out into the hands of the domain experts then your iteration speed becomes really fast”transcript, stated

Deployment abstraction

Chose App Factory over bespoke deployment for each app.

Rationale: Apps need repeatable choices for clusters, access control, distribution, and cost controls.

“our app deployment phase is like as close to like a CI/CD pipeline as possible.”transcript, stated

Gotchas (what bit them)

Fully agentic workflow automation was not enough.

Root cause: Complex financial instruments require domain expertise and tacit business knowledge.

Resolution: Design a human-in-the-loop sandbox and app-factory system.

“We tried this with agentic systems doesn't quite work right now because of the complexity”transcript, stated

Deployment became a separate bottleneck after prompt/template work.

Root cause: AI apps need distribution, access control, cluster selection, and cost controls.

Resolution: Use an App Factory to make deployment CI/CD-like.

“I've kind of built this app now what how do I get this to deployment and it's this whole other set of challenges”transcript, stated

Simple prompt templates were insufficient for extraction.

Root cause: Financial extraction fields need QC checks, constraints, data types, and dependencies.

Resolution: Provide richer extraction-template configuration in the Sandbox.

“they need far more sort of like greater configuration capabilities than just like configuring prompts and configuring the data types”transcript, stated

Evaluation

BlackRock evaluates through domain-expert extraction comparison, QC checks, validation constraints, four-eyes review, deployment readiness, and time-to-app reduction.

Metrics: time to build app · field validation pass · QC check pass · inter-field dependency correctness · human review completion · deployment readiness

“run extraction on the set of documents and then compare and contrast the results of these extractions.”transcript, stated
“multiple QC checks on the result values. I need to have a lot of validations and constraints on the fields”transcript, stated

Outcomes

The framework is aimed at BlackRock investment operations, where internal app needs span extraction, workflows, Q&A, and agentic systems.

“we able to compress time bring it down to like a couple of days”transcript, stated