Senior Software Engineer - Special Projects
Status
Salt Lake City, USA
Full time
Remote
Compensation is not specified
Role
Software Engineer
Description
- Circle is a pioneering fintech firm operating at the forefront of the expanding realm of digital finance, facilitating the seamless transmission of value globally with unprecedented speed and cost-efficiency compared to traditional payment systems. Their cutting-edge platform presents immense opportunities for economic growth and inclusivity through transformative advancements in payments, commerce, and markets.
Overview:
- Operating with a commitment to transparency and consistency, Circle is venturing into robust global markets while upholding core values such as Multistakeholder engagement, Mindfulness, Excellence-driven mindset, and High Integrity. Employees uphold these values and adapt constantly in a telecommuting environment, fostering a collaborative space where diverse perspectives are valued, and innovation thrives.
Responsibilities:
- Circle is seeking an adept Smart Contract Engineer to join the USDC Smart Contract team. As a Senior/Staff Software Engineer on this team, the incumbent will spearhead the technical aspects of designing and expanding smart contracts for USDC across multiple blockchain ecosystems like Ethereum, Solana, Cosmos, among others.
Primary Tasks:
- Design, develop, and deploy secure smart contracts to facilitate smooth and safe transactions.
- Enhance existing smart contracts to boost developer productivity, safety, and overall efficiency.
- Implement security protocols and performance enhancement techniques.
- Conduct risk evaluations regarding smart contract development on diverse blockchain platforms, identifying vulnerabilities and applying mitigation strategies to augment security and resilience.
Qualifications:
Senior Software Engineer (III)
- More than 4 years of professional software development expertise, encompassing internships.
- Over 2 years of proven experience in smart contract development on blockchain platforms.
- Proficiency in programming languages commonly used for non-EVM smart contracts like Rust, Go, or equivalent.
- Recorded expertise in a prominent non-EVM blockchain ecosystem such as Cosmos or Solana.
- Strong focus on security best practices, implementing robust security measures in smart contract development.
- Stay current with blockchain development trends to drive innovation and progress.
Staff Software Engineer (IV)
Include all requirements of a Senior Software Engineer and:
- Over 7 years of professional software development experience, including internships.
- More than 4 years of proven smart contract development experience on blockchain platforms.
- Adept in non-EVM programming languages and tech stacks.
- Thorough comprehension of blockchain technology principles and various blockchain and web3 protocols.
- Proficiency in mentoring junior engineers, team leadership, and effective cross-functional collaboration.
Additional Information:
This position supports day-one PERM sponsorship for qualified candidates.
Compensation is determined by various factors like relevant experience, skill set, qualifications, and organizational needs, offering equitable compensation ranges and comprehensive packages, including Equity & Benefits encompassing medical, dental, vision, and 401(k). Circle offers a flexible vacation policy, 10 paid sick leave days annually, and 11 paid holidays in the U.S.
Circle fosters diversity and is an equal opportunity employer, unequivocally condemning discrimination based on race, religion, national origin, gender, sexual orientation, age, marital status, veteran status, or disability. They adhere to required laws in certain locations by participating in the E-Verify Program.
Skills Required
Circle
Website
www.circle.comCompany size
Not specified
Location
United States
Description
Not specified
Status
Sirex
Junior AI Engineer
Full time
Remote
Role:
Join one of our fast-growing portfolio startups and help build simple AI features. You’ll work with large language models, create basic automations and chat tools, test ideas, fix small bugs, and integrate AI into everyday products.
Skills & Requirements:
0–2 years of experience (fresh graduates or self-taught welcome)
Basic Python knowledge
Interest in AI, LLMs or chatbots (personal projects are a big plus)
Quick learner who enjoys trying new things
Good English for team communication
Salary: $95,000 – $135,000 USD base + equity in the startup + full benefits
Description:
Sirex.vc not only invests — we actively help our portfolio companies hire great people. This Junior AI Engineer role is inside one of our AI-native startups. You’ll get real hands-on experience, learn from the best, and build things users actually use — all with full support from the Sirex team.
High risk. Zero apologies.
Join one of our fast-growing portfolio startups and help build simple AI features. You’ll work with large language models, create basic automations and chat tools, test ideas, fix small bugs, and integrate AI into everyday products.
Skills & Requirements:
0–2 years of experience (fresh graduates or self-taught welcome)
Basic Python knowledge
Interest in AI, LLMs or chatbots (personal projects are a big plus)
Quick learner who enjoys trying new things
Good English for team communication
Salary: $95,000 – $135,000 USD base + equity in the startup + full benefits
Description:
Sirex.vc not only invests — we actively help our portfolio companies hire great people. This Junior AI Engineer role is inside one of our AI-native startups. You’ll get real hands-on experience, learn from the best, and build things users actually use — all with full support from the Sirex team.
High risk. Zero apologies.
Payment in Crypto
Sirex
AI Agent Engineer
Full time
Remote
Role:
Join one of our high-conviction AI-native portfolio companies and build autonomous AI agents from the ground up. You’ll design agent architectures, implement tool-calling & memory systems, connect them to browsers/shell/APIs, run long-horizon tasks, and ship features that make the product feel alive and truly useful.
Skills & Requirements:
2–5 years building LLM-powered agents (LangGraph, CrewAI, ReAct, custom frameworks)
Strong Python skills + experience with tool calling, RAG, vector stores and evaluation
Bonus: familiarity with browser automation, self-hosted models or decentralized compute
Fast executor who loves shipping in ambiguity
Passion for agents that actually do real work (not just chat)
Salary: $160,000 – $230,000 USD base + meaningful equity (in the portfolio company) + full benefits + carry from Sirex network
Description:
Sirex.vc doesn’t only write checks — we actively help our portfolio companies recruit the best people on the planet. This AI Agent Engineer role is inside one of our fastest-moving startups building the next generation of autonomous agents. You’ll get direct support, intros, and operational help from the Sirex team while working on frontier technology that can change how the world uses AI.
High risk. Zero apologies.
Join one of our high-conviction AI-native portfolio companies and build autonomous AI agents from the ground up. You’ll design agent architectures, implement tool-calling & memory systems, connect them to browsers/shell/APIs, run long-horizon tasks, and ship features that make the product feel alive and truly useful.
Skills & Requirements:
2–5 years building LLM-powered agents (LangGraph, CrewAI, ReAct, custom frameworks)
Strong Python skills + experience with tool calling, RAG, vector stores and evaluation
Bonus: familiarity with browser automation, self-hosted models or decentralized compute
Fast executor who loves shipping in ambiguity
Passion for agents that actually do real work (not just chat)
Salary: $160,000 – $230,000 USD base + meaningful equity (in the portfolio company) + full benefits + carry from Sirex network
Description:
Sirex.vc doesn’t only write checks — we actively help our portfolio companies recruit the best people on the planet. This AI Agent Engineer role is inside one of our fastest-moving startups building the next generation of autonomous agents. You’ll get direct support, intros, and operational help from the Sirex team while working on frontier technology that can change how the world uses AI.
High risk. Zero apologies.
Payment in Crypto
Sirex
Investment Analyst
Full time
Remote
Role:
Help the team find and evaluate early-stage startups. Search for promising projects, do quick market checks, prepare short summaries, track portfolio companies, and assist with basic due diligence.
Skills & Requirements:
0–2 years of experience (recent graduates or startup background welcome)
Strong interest in AI, crypto, and new technologies
Good at research, writing clear notes, and using spreadsheets
Organized, fast learner, and comfortable with uncertainty
English at upper-intermediate level
Salary:
$85,000 – $115,000 USD base + small carry + full benefits
Description:
At Sirex.vc we back crazy ideas in AI and decentralized tech. As Investment Analyst you’ll be right in the middle of the action — scanning hundreds of startups every week, learning how real venture works, and helping decide where we put money. Perfect first step into VC for someone hungry and smart. High risk. Zero apologies.
Help the team find and evaluate early-stage startups. Search for promising projects, do quick market checks, prepare short summaries, track portfolio companies, and assist with basic due diligence.
Skills & Requirements:
0–2 years of experience (recent graduates or startup background welcome)
Strong interest in AI, crypto, and new technologies
Good at research, writing clear notes, and using spreadsheets
Organized, fast learner, and comfortable with uncertainty
English at upper-intermediate level
Salary:
$85,000 – $115,000 USD base + small carry + full benefits
Description:
At Sirex.vc we back crazy ideas in AI and decentralized tech. As Investment Analyst you’ll be right in the middle of the action — scanning hundreds of startups every week, learning how real venture works, and helping decide where we put money. Perfect first step into VC for someone hungry and smart. High risk. Zero apologies.
Sirex
Operating Partner
Full time
Remote
Role:
Work side-by-side with portfolio founders to scale their companies at speed. Lead talent acquisition for critical roles, build operational systems and processes, shape go-to-market strategy, track key metrics, and support follow-on fundraising.
Skills & Requirements:
4–6+ years of hands-on experience in high-growth startups (previous Head of Operations, Chief of Staff, or founding team member strongly preferred)
Deep understanding of AI, decentralized infrastructure or developer platforms
Strong talent network and proven ability to recruit top technical talent
Exceptional execution skills and comfort operating in ambiguity
Data-oriented and systems thinker
Salary:
$175,000 – $245,000 USD base + significant carry + equity + full benefits
Description:
Sirex.vc doesn't just invest — we build alongside our founders. As Operating Partner, you will be the difference-maker for our portfolio companies, rolling up your sleeves to help them move faster and smarter than their competition. If you live for turning chaos into momentum and want to help create the defining companies of the next decade, this is your role. High risk. Zero apologies.
Work side-by-side with portfolio founders to scale their companies at speed. Lead talent acquisition for critical roles, build operational systems and processes, shape go-to-market strategy, track key metrics, and support follow-on fundraising.
Skills & Requirements:
4–6+ years of hands-on experience in high-growth startups (previous Head of Operations, Chief of Staff, or founding team member strongly preferred)
Deep understanding of AI, decentralized infrastructure or developer platforms
Strong talent network and proven ability to recruit top technical talent
Exceptional execution skills and comfort operating in ambiguity
Data-oriented and systems thinker
Salary:
$175,000 – $245,000 USD base + significant carry + equity + full benefits
Description:
Sirex.vc doesn't just invest — we build alongside our founders. As Operating Partner, you will be the difference-maker for our portfolio companies, rolling up your sleeves to help them move faster and smarter than their competition. If you live for turning chaos into momentum and want to help create the defining companies of the next decade, this is your role. High risk. Zero apologies.
Payment in Crypto
Sirex
Venture Associate – AI & Decentralized Infrastructure
Full time
Remote
Role:
Source, diligence, and close early-stage investments in AI-native technologies, decentralized protocols, developer platforms, and compute infrastructure. Work side-by-side with founders post-investment on strategy, hiring, product roadmap, and scaling operations.
Skills & Requirements:
2–4 years in venture capital, startup operations, or technical role (engineering/product background strongly preferred)
Deep understanding of AI models, blockchain infrastructure, open-source ecosystems, and compute markets
Proven ability to build founder networks and spot asymmetric opportunities early
Exceptional analytical skills, written/verbal communication, and comfort with high-uncertainty decisions
Self-starter who moves fast and doesn’t need hand-holding
Salary:
$150,000 – $220,000 USD base + meaningful carry + equity upside + full benefits
Description:
Sirex.vc backs visionary founders redefining the open digital economy with asymmetric, high-conviction bets. We move at startup speed and expect the same from our team. As Venture Associate you’ll be on the front lines hunting the next 100x opportunities in AI, crypto infra, and compute — while rolling up your sleeves to help portfolio companies win. High risk. Zero apologies. If you live for the thrill of early-stage tech and want to build the future instead of just funding it, we want to talk.
Source, diligence, and close early-stage investments in AI-native technologies, decentralized protocols, developer platforms, and compute infrastructure. Work side-by-side with founders post-investment on strategy, hiring, product roadmap, and scaling operations.
Skills & Requirements:
2–4 years in venture capital, startup operations, or technical role (engineering/product background strongly preferred)
Deep understanding of AI models, blockchain infrastructure, open-source ecosystems, and compute markets
Proven ability to build founder networks and spot asymmetric opportunities early
Exceptional analytical skills, written/verbal communication, and comfort with high-uncertainty decisions
Self-starter who moves fast and doesn’t need hand-holding
Salary:
$150,000 – $220,000 USD base + meaningful carry + equity upside + full benefits
Description:
Sirex.vc backs visionary founders redefining the open digital economy with asymmetric, high-conviction bets. We move at startup speed and expect the same from our team. As Venture Associate you’ll be on the front lines hunting the next 100x opportunities in AI, crypto infra, and compute — while rolling up your sleeves to help portfolio companies win. High risk. Zero apologies. If you live for the thrill of early-stage tech and want to build the future instead of just funding it, we want to talk.
Payment in Crypto